03 Allroad BHW/02X TDI Conversion

[blairdude]

Hey all, fairly new here, but last year I picked up an 03 Allroad with the intention of swapping in a diesel engine and building a nice fuel efficient/luxurious daily driver
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Took it home and picked up some things at a self-serve wrecker on the way home. When I bought it, the sunroof wouldn't close fully, and the hatch wouldn't latch, along with some other minor issues and of course the classic soft-touch material coming off. Also managed to grab a 02X there (GVE from a B7 2.0T A4) along with some bits for the conversion.
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I had pulled a BHW engine from a 04/05 Passat from the local Pick'n'Pull about 6 months earlier, and was pleasantly surprised to see that someone had already installed a geared BSM in it. I was originally planning on deleting it if it still had the original chain-driven BSM, but I was pretty happy to find that and I'll leave it be. Hex shaft didn't appear to have any noticeable wear on it either.
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Another pleasant surprise was no sludge buildup in the engine at all. Was able to get the oil pan perfectly clean with minimal effort. The oil pan also already had an oil level sender in it which doesn't seem to have been common on the B5.5 TDIs.
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Going further with the engine prep, I installed a Colt Stage 2 cam (they're local-ish to me), new INA lifters, with the springs removed as recommended by Colt, new timing belt, and BPW (B7 TDI) accessory bracket installed. I decided to go with the BPW accessory setup as it simplifies lots of things; puts all the accessories on one side of the block, no more clutch fan, 1 belt instead of 2. Belt tensioner crosses over to the CR TDI engines sold in North America, and the B5 power steering pump can be used with a 6-rib pulley swapped over (I grabbed one from an ALH car in the yard). For the alternator I'll be running a 140A unit from a Mk6 Jetta, but there are lots of alternator options that will fit.
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Saw that 1.8T cars came with a heat shield on the driver's side engine mount, so I figured why not grab it and swap it over. Just needed to be riveted on. I trimmed a few areas to make it easier to access the engine mount nut
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For a clutch, I decided to go with a B7 TDI DMF/clutch from Europe, which also requires a bellhousing spacer, different starter, and different turbo brace. More on that later. Also had to change out the dowel pins in the block to make up for the bellhousing spacer thickness. They were pretty easy to change out.
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[blairdude]

For the pilot bearing, the BHW has a shallower protrusion because it came with an automatic transmission. My solution to this involved using a 2.0T B7 pilot bearing (longer), and inserting a washer into the end of the crank so that the bearing can be fully driven in and supported at the rear. I won't know for sure how this lasts until the car is running and driving, but I think it should be OK. This gave me a good amount of engagement with the input shaft, which I checked by bolting up the transmission without the clutch installed.
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The clutch (Luk brand) has a self-adjusting pressure plate and it didn't look like the self-adjusting mechanism was fully reset as it arrived. Not a big issue though, it was pretty easy to do by tossing the pressure plate in my Harbor Freight press. Then I was able to get it installed and the transmission fully bolted up. I used the bellhousing bolts from the 2.0T B7 which were all the perfect length.
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The plastic cover for this crank sensor hole was missing on my transmission, so I just used some aluminum, tin snips, and a worn-out rotor retaining bolt to cover the hole.
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[ShelbyM3]

Rad! I’ll be following this. Love the idea and wish there were more diesels.


Sent from my iPhone using Audizine Forum

[blairdude]

Next I got to work removing the old drivetrain and suspension. It went pretty smoothly, even the pinch bolts didn't give me much trouble, but some of the suspension top mount bracket bolts stripped the aluminum upon removal. I'm so thankful the engine bay won't be so crowded after this. Sold the old engine (still in good running condition) to someone for a B7 A4 conversion.
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Next I got to work prepping the front subframe with new bushings. Used the drill method to separate the top part of the rubber, then the rest of the bushings came out pretty easily. Since Allroad subframe bushings are almost NLA, I got Lemforder brand A6 replacements, which appear to be identical except for a couple minor differences. I drilled holes in the new bushings for the dowel pins to attach the Allroad subframe spacers, and the old rear bushings had plastic inserts in them that the new rear bushings didn't come with. I was able to transfer them over to the new bushings however. I assume they're there to stiffen up the bushing in the one area. After finishing prepping the subframe, I put it in the car with the 02X transmission crossmember for a quick test fit.
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[blairdude]

Took a brief detour to re-seal this RS6 rack that I ordered from Europe, as when I pulled the tie rod boots off, there was a small amount of power steering fluid in them. The A6 rack seal kits seem to be NLA, but I was able to find an A8 kit that I combined with an A4 ZF seal kit to get all the seals I needed. Hopefully I got everything right, but I took my time and tried to be very careful with disassembly and reassembly. There were no guides I could find online, but there is a Youtube video of a BMW ZF rack rebuild, and the majority of the process is the same. The B5 rack kit had all of the necessary seals except the rack center teflon seal, and the right side rack seal, which have a larger O.D. on the C5 racks.
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[blairdude]

Next was designing the mods and brackets required to adapt the 02X to the C5 chassis. On all other C5s and B5s, the crossmember used on B6/7 02X cars is unusable without cutting/welding because too much material needs to be removed from the crossmember to clear the unibody, most specifically on the left side. There IS an alternate crossmember (8E0399263BE) with only a single hump on the right side that may be a much closer fit to B5/C5s, but as far as I can tell they were only used on CR TDI cars with the 0A3 transmission, and therefore one would have to be imported from Europe to test fit. On the Allroad, however, the 25mm subframe spacers give adequate room to fit the crossmember with relatively minor grinding to clear the floor pan. The two main crossmember bolts mount to the same holes as the rear subframe mounts, so simply bolting it up with those two bolt holes lines everything up enough to be able to make some adapter brackets without having to worry too much about everything being aligned properly. The crossmember also has all of its mounting holes slotted to allow for some variability/subframe adjustment.

My solution to mounting the transmission involved making some adapter brackets out of 3/4" aluminum flat bar (not the exact right height but close enough for me) that basically provide the two other mounting points per side used on the 02X crossmember, themselves bolting to the rear subframe brace bracket bolt holes that they essentially replace. Because the brackets take up more space than the braces they replace, I also needed to scrape some undercoating off the floor pan so that the brackets could lay flat. I also drilled some extra holes in the brackets to clear spot welds on the floor pan. Drilled/tapped the brackets to M10x1.5 and used some factory engine mount bracket bolts (cut a bit short) to mount the crossmember to the brackets. The two auxiliary mounting points on the crossmember on each side are on different planes, but I knocked some spacers out of some B7 auto rear subframe brace brackets in the junkyard and they turned out to be perfect for making up the difference in height. The brackets are attached to the body with two bolts using the original M8x1.25 bolt holes already present in the body, one on each side is a countersink bolt as it is covered by the crossmember when it is in place.

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The original subframe bolts still reach the threads in the body even with the extra stack height of the crossmember, but I opted to use N91227901 for the two subframe bolts going through the crossmember, which are used on B8 chassis vehicles and are 15mm longer than the originals. All bolts securing the crossmember to the car have 18mm heads which is nice for consistency.

BPW cars which use this transmission support the rear catalytic converter flange with a mount to the transmission; probably one of these exhaust mounts would be a direct fit or close to it, but I decided to just make my own out of stainless sheet metal. It attaches to the same mounting positions that the BPW bracket would, and I reused one of the exhaust mounts from the original 2.7/auto drivetrain.

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[blairdude]

The 02X shift linkage is a very good fit already to the C5 chassis. Besides the complete B6/7 02X linkage, also a B5/C5 plastic shift linkage holder is needed to make it bolt right in. The B6/7 linkage is bolted to the plastic box in 4 locations, and can be removed from its original plastic box and installed into the C5/B5 one as a complete unit, keeping the adjustment correct. If adjustment is needed, it's probably best to adjust it in its donor first, as adjustment relies on being able to measure between one of the bolts on the linkage and one of the plastic box mounting nuts (which changes when the plastic box is changed). The rubber boot on the 02X linkage is a direct fit for the C5/B5 box as well. Other than that, the upper plastic cover from the B6/7 linkage needs some minor trimming to clear the C5 center console. The C5 shifter insulation fits overtop the whole assembly perfectly.

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For the shifter knob/boot, I combined a bunch of parts to make something nice and custom. B6/7 wood grain shift knob, combined with a B6/7 'Swing Grey' boot, fit over a C5 lower shift boot ring, and installed in an 01 Allroad auto shifter trim piece with the lower boot mounting cage transferred over from another C5 manual shifter trim piece.

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Manual conversion was topped off with pedals from a B5 FWD manual car in the junkyard, along with a B5 hydraulic line, master and slave cylinders. Nothing really special there. The Allroad has a separate part number for the clutch line (presumably because the subframe spacers increase the distance), but the B5 line had plenty of length to reach no problem. My pedals came from an early year B5, but the clutch safety switch was a direct fit, and as long as the master cylinder matches the clutch pedal, the years seem to mix and match just fine. Since my pedal bracket is an '03, I did have to use a clutch cruise cancel switch for the newer pedal assembly.

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[Bordom]

This is baller. I should be on Audizine more often like I used to lmao

[ShelbyM3]

You’re an inspiration! Such clever and OE solutions! I was hoping you’d have an update.


Sent from my iPhone using Audizine Forum

[blairdude]

With the transmission crossmember sorted out, it was time to install the drivetrain in the car. The whole thing slipped in much easier than the twin turbo V6. I attached the wiring harness to the engine prior, since, while possible to install it separately, it goes through some tight spaces at the rear of the engine. The main starter wire needs to be used from the BHW donor, as it is heavier gauge to supply enough power to the more powerful diesel starter. One thing to note; the left side engine mount uses a different hole in the engine mount bracket for the stud compared to the V6 engine. Nicely, Audi left both bolt patterns in the Allroad engine brackets even though it never came with a 4 cylinder.

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With the drivetrain in, I could finally test my theory that the 2.7 A/C compressor would bolt right up to the BPW accessory bracket, and I was right! However, the 2.7 pulley unfortunately does not line up with the rest of the BPW accessories or the crank pulley. More on a solution for that later.

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On the transmission end, the auto driveshaft and 02X driveshaft shield bolted right up with zero issues. Like it was meant to be. One thing I missed in the last post, was that some of the heat shielding around the crossmember needed to be trimmed as it interfered with the crossmember a bit. Very easily sorted with some tin snips.

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Ordered a BPW engine cover from Europe, and modified it so that it will push/pull on and off instead of using 3 10mm nuts. It's similar to converting an ALH engine cover (which I did on my daily driver Jetta), but some of the rubber bushings needed trimming to fit nicely under the caps. There's also a stud on the driver's side intake pipe that has to be punched out so it can be replaced with a ball stud.

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[blairdude]

More on engine mounts. The right side BHW engine mount was very close to the wires going to the starter with the longer 240mm clutch starter. I probably could have ground the BHW bracket enough to have a comfortable gap, but I ultimately decided to just replace it with a BPW mount bracket, as it wasn't super expensive to order a used one. I transferred over the 1.8T heat shield to it and reinstalled. The main ground wire from engine to chassis needed to have the engine side terminal bent a bit to lay flat; the BPW wire is likely longer and fits a different way, but this worked just fine. The 240mm clutch starter also requires a different turbo brace, as the BHW one is in direct interference with the starter.

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Moving onto the snub mount, one of my original goals for this project was to find a way to avoid cutting up the Allroad rad support to fit the Passat crossover pipe/snub mount, which would also require cutting/welding the Passat pipe for fitment and to make up for the 25mm subframe spacers. This is what all other Allroad swappers that I know of have done. I was also intrigued by knowing that the V6 TDI A6s and Allroads in Europe used a front mount intercooler from the factory. Using the BPW accessory bracket makes it so the BHW snub mount 'cup' has almost no adjustment since it interferes with the accessory belt routing. I was originally hoping a B7 2.0T snub mount bracket would be close to lining up to the V6 snub mount cup, but once I was able to test fit, it was way off.

Quick side note; interestingly the BHW/BGW oil pan has both snub mount bolt patterns on it; side mount bosses that fit the B6/7 snub mount bracket, and front mount bosses for the B5 snub mount cup. This is unique and odd, as the B5 1.8T pans only have the mount bosses at the front of the pan, and B6/7 gasser pans only have the mount bosses on the side of the pan.

So I will be using a front mount intercooler, and decided to make a custom snub mount bracket to use the original V6 rad support and snub mount cup. I started by cutting the end off a B7 snub mount bracket, and using a step drill bit (didn't have a countersink bit large enough) to drill out the end to be able to fit a bolt with a tapered washer through it and bolt it to a piece of 3/8" aluminum flat bar which in turn bolts to the front of the pan. Tapered washer was stolen off a BMW M14 wheel bolt, and I used a long M14 bolt to bolt through the snub mount nub into the flat bar, with a nut on the other end. The snub mount needed to extend a bit further, so I sandwiched a leftover piece of 3/4" flat bar from making the trans crossmember adapters in between, and it turned out perfectly. The mount is designed to fit right in the middle of the adjustment range of the V6 mount cup.

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The BHW snub mount itself was a much looser fit in the V6 mount cup vs the BHW mount cup, so I riveted a piece of aluminum to one end of the V6 mount cup, and now it's just as tight a fit as it's meant to be. Perfect fitment now!

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[blairdude]

Next was finalizing the accessory setup. The 2.7 A/C compressor bolted up to the BPW bracket, but as mentioned earlier, the pulley did not line up with anything else. So after a bit of searching through vehicles that use the same type of compressor, I came up with the hypothesis that a 99-03 Saab 9-5 clutch/pulley would rectify that, so I ordered a new replacement clutch set. To my delight, the Saab pulley turned out to be a perfect fit and lined up the compressor pulley with everything else.

With the new compressor mounting position (it's not identical to where it ends up on the V6), the A/C lines hung quite low, but I was able to bend them without too much trouble to tuck under the oil pan, and I made hold-down brackets on each side of the oil pan to secure them in place. They end up very very close to the front sway bar, but hopefully with some rubber around them, they won't cause much in the way of vibrations when installed in the car. Having the A/C compressor on the left side of the engine also meant that the BHW lower rad hose would interfere with the compressor body, but I found by carefully cutting the plastic crimps on the main hose, I could flip it around, and get all the clearance I needed. It's actually surprising that flipping it around and clamping it back on was all that was needed for perfect fitment of the rad hose. A B6/7 hose cannot be used because the quick connect fittings are indexed differently.

For the alternator, I pulled a Mk6 Jetta 140A alternator from the local junkyard, which is a perfect fit, along with a B7 2.0T power steering pump, and ordered a new tensioner and idler pulley online. The tensioner interchanges with Mk5/6 CR TDI engines, however, the idler pulley is a Euro-only part (one of a handful of parts on this build). The BHW power steering pump would have fit the bracket with the 3 main mounting holes, however, the 4th mounting point at the rear of the pump would not have been usable. It also would have needed a 6-rib pulley swapped over (easily found on many Mk4 chassis vehicles). The B7 pump was just overall a better fit, and I also used B7 high and low pressure lines. To top it all off, the belt I used interchanges with a Mk4 ALH TDI, keeping it in the TDI family.

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Note - in the future, I may eventually swap to a direct drive A/C compressor used on B6 and B7 cars. As far as I can tell, these compressors will be compatible with the existing A/C lines. Main caveat is that some relatively minor rewiring would be required, as well as adding an additional evaporator outlet temp sensor inside the car (found on 4.2 Allroads and 3.0L A6s which also use a direct drive compressor). The climate control module can simply be coded for the change after the necessary wiring is done. The B6/7 compressors use a smaller pulley, so they would also require a different belt length (unknown at this time).

[blairdude]

With the 02X transmission, I obviously needed different axles than the ones with the auto trans. The few 02X Allroad conversions I found typically use a right side B6/7 manual axle on the left, and an Allroad 01E axle on the right. However, Allroad OEM axles are getting quite hard to find these days, and there aren't many options out there that are close enough to the right length. I wanted to be able to use all levels of the air suspension as well, so having full range was important to me.

I experimented a bit with C6 manual axles (euro-only), but for starters, to be usable, they need a B6/7 S4 outer joint in place of the original, since the C6 outer joint has no ABS ring on it. With S4 outer joints installed, the C6 left axle ends up being almost the exact same length as a B6/7 right axle, yielding no benefit, and the C6 right axle ends up being too long on the right side to the point where it will push the drivetrain to the left at around level 1/2. With this info, it would seem that at least a C6 left axle is usable on the left side with an S4 outer joint, but then it turned out that the larger S4 joint causes the boot to rub on the air shock at full lock, at least with the suspension at full droop. I'll keep one around at least as a spare that can be used in a pinch.

So with the C6 axles being a complete dud, I needed a different solution. I then stumbled upon this aftermarket part that ends up being a solution to two hurtles (https://www.ultraperformance.co.uk/0a3-gearbox-vss-trigger-wheel). This trigger wheel is thick enough that it allows me to use two B6/7 right side axles on both sides of the car, using this trigger wheel on the right side. It also makes a very easy solution to the lack of a VSS on the 02X transmission (which I had some other ideas for, which I'll explain in a bit). They do also make a VSS sensor bracket that is meant to work with this trigger wheel, but since theirs is designed to bolt to the left side of the transmission, it wouldn't work for me. So for a VSS, I made my own sensor mount to work on the right side of the transmission, and for the sensor itself, I used a BMW intake cam sensor (used on various BMW I6s from around 01-06). This sensor is an ideal choice, as it not only shares its plug with the original Allroad VSS, but the wire is long enough to reach the original position as well. Caveat being that an additional wire needs to be added to the original VSS plug; the original uses only a ground and signal wire, but the BMW sensor needs an additional wire with +12V (pin can be added to the Audi/VW plug fairly easily). The sensor mount has some adjustability in the bolt holes, so that the sensor can be placed the ideal distance from the trigger wheel.

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With the additional thickness of the trigger wheel, I needed longer axle bolts to reach through. I found I could use rear diff axle bolts (also used on the rear of the B7) by cutting about 10mm off the ends. I chose these bolts specifically because they have the same triple square head as the originals, for consistency when doing maintenance in the future.

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There are some alternate solutions for the VSS as well if using an Allroad 01E axle. The same company makes a thin trigger wheel that doesn't add any thickness. If the chassis has ABS 5.7 (module in the engine bay, rather than behind the glove box with 5.3, which is what my car has), a pin can be added to the module connector that supplies the correct VSS signal, and can be wired to the signal wire on the engine harness. I was also originally thinking I could make a VSS sensor bracket using the same BMW sensor to read off the axle flange itself (which would be 6 pulses per rev vs 8). And finally, there are 4 speed output wires on the ABS 5.3 module, one of which is wired to the headlight range module in the original body harness, however, they output a much higher pulse count than what the cluster expects. In anticipation of ending up with a non-standard VSS signal, I wrote a TunerPro XDF and speedo checksum DLL (http://nefariousmotorsports.com/forum/index.php?topic=21459.0title=) to allow for programming custom K-values into the cluster, which should allow a fairly wide range of signal pulse counts to be used. I did some bench testing to confirm that it would allow for 6 pulses per rev to be used, but at some point below that (not sure exactly where), it defaults to something like a stock pulse count. I do not at this point in time know the upper range of allowable 'K-values'. There are actually 6 stored in the cluster, 3 input counts and 3 output counts. The regular A6 uses two of them (input and output), and when coded for 'Allroad', an alternate two are used. I'm not at this point sure what the other 2 are used for. Theoretically, this could also be used to program the cluster for two different tire sizes if using different tires for winter and summer, and use the 'Allroad' coding to switch between the two. The 'Allroad' coding does not seem to affect anything besides which K-values are used; the suspension warning light works with and without being coded for Allroad. This XDF can also just be used to correct for non-standard tire sizes, or to increase the accuracy of the speedo/odo, since the stock values are generally a compromise to allow for the range of tire sizes used from the factory.

[FatMongo]

Such an amazing thread! Thanks for all the info on using an 02X in the Allroad.

[blairdude]

Such an amazing thread! Thanks for all the info on using an 02X in the Allroad.

Thanks! It's worth noting that almost everything 02X also applies to the 0A3, with the only differences being the shifter linkage (still fits the same but linkage is different) and the rear driveshaft (0A3s have a different length). Crossmember fitment and front axle fitment should be the same.

[FatMongo]

Hey Bud,

Would you mind going into a little more detail on the VSS solutions? I have access to what appears to be a good 02X and rear diff and am considering this route really hard. My car is an 04 Allroad, has ABS 5.7 (I believe) and I would want to try to use OEM Allroad axles. So for a VSS solution, you are saying to add a pin to the connector going to the ABS module and run that wire to the sensors at the axle?

[blairdude]

Hey Bud,

Would you mind going into a little more detail on the VSS solutions? I have access to what appears to be a good 02X and rear diff and am considering this route really hard. My car is an 04 Allroad, has ABS 5.7 (I believe) and I would want to try to use OEM Allroad axles. So for a VSS solution, you are saying to add a pin to the connector going to the ABS module and run that wire to the sensors at the axle?

First, there's no inherent advantage to using OEM Allroad axles other than maybe you have them already and they fit. The B6/7 manual axles use the same or very similar inner CV joint with all the plunge needed to keep the air suspension happy at all levels. I don't actually know if both sides fit, but the right side Allroad axle is said to fit on the right side. It is only about 6mm longer (compressed) than the B6/7 right side manual axle I'm using on the left side of my Allroad. The axle spacer/tone ring I'm using spaces the axle out about 16mm. I have a feeling that my setup is actually better than using an Allroad axle on the right side, because the shaft will stay more in the middle of the range of axle length, instead of further out. I have no doubt an axle spacer could be made up without the tone ring. Easier access to axle replacements is a welcome bonus.

Onto the VSS, Pin 33 on the ABS 5.7 connector outputs a speed pulse that matches what the cluster is needing. The original VSS plug has 3 wires, and the middle (signal) wire on the VSS plug goes directly to the cluster. If you wire pin 33 from the ABS 5.7 connector (won't be present already in the harness; you'll have to add the pin yourself) to the VSS plug pin #2, that's all you need to get a speed signal to the cluster from the ABS module. The other 2 wires on the VSS plug will no longer be needed and can be left empty. For a cleaner wiring solution, you can get a male 3-pin plug that fits the VSS connector new or snip one from a junkyard; you can find them on some BMW cam sensors among other things.

[FatMongo]

First, there's no inherent advantage to using OEM Allroad axles other than maybe you have them already and they fit. The B6/7 manual axles use the same or very similar inner CV joint with all the plunge needed to keep the air suspension happy at all levels. I don't actually know if both sides fit, but the right side Allroad axle is said to fit on the right side. It is only about 6mm longer (compressed) than the B6/7 right side manual axle I'm using on the left side of my Allroad. The axle spacer/tone ring I'm using spaces the axle out about 16mm. I have a feeling that my setup is actually better than using an Allroad axle on the right side, because the shaft will stay more in the middle of the range of axle length, instead of further out. I have no doubt an axle spacer could be made up without the tone ring. Easier access to axle replacements is a welcome bonus.

Onto the VSS, Pin 33 on the ABS 5.7 connector outputs a speed pulse that matches what the cluster is needing. The original VSS plug has 3 wires, and the middle (signal) wire on the VSS plug goes directly to the cluster. If you wire pin 33 from the ABS 5.7 connector (won't be present already in the harness; you'll have to add the pin yourself) to the VSS plug pin #2, that's all you need to get a speed signal to the cluster from the ABS module. The other 2 wires on the VSS plug will no longer be needed and can be left empty. For a cleaner wiring solution, you can get a male 3-pin plug that fits the VSS connector new or snip one from a junkyard; you can find them on some BMW cam sensors among other things.


Thanks for the phenomenal input!

Couple of other questions... Im assuming you used the A4 differential behind the GVE as well? Any issues with bolting it in to the Allroad?

Also, did you use the OEM Allroad driveshaft behind the 02X and are there issue with that or does it fight correctly?

[blairdude]

Thanks for the phenomenal input!

Couple of other questions... Im assuming you used the A4 differential behind the GVE as well? Any issues with bolting it in to the Allroad?

Also, did you use the OEM Allroad driveshaft behind the 02X and are there issue with that or does it fight correctly?

I actually used a rear diff from an auto 2.7 A6 sedan that was in the junkyard. Was a direct fit, and didn't even need to change the axle cups. That said, B6 and B7 (and B5.5 4motion Passats) all use the same mounting points on the diff case, and will all bolt into a C5. Depending on what axle cups are on the diff, they may need to be swapped out for your original ones (single bolt on each side). The important thing is that the ratio matches. There is a 3 letter code stamped on the bottom of the differential that you can use to verify the correct ratio (3.889 in my case). The correct ratio can be found on all of the previously mentioned vehicles, depending on how it was optioned.

The A6 diff I used had axle cups that were shaped slightly differently than the Allroad ones, but as far as I can tell, it's because the Allroad diff has extra dust shields that the A6 diff does not have. Removing the dust shields to swap over would have just destroyed them. I have used the car on all 4 levels with zero problems.

Yes I used the original Allroad automatic driveshaft, and it was a direct fit.

[FatMongo]

Thanks for all the info you have inspired me!

I went ahead a pulled the trigger on the 02X and rear diff from a B7 A4. Its a GVE trans and diff - so 3.89:

https://live.staticflickr.com/65535/53384534571_af05175571_h.jpg (https://flic.kr/p/2pkpGeR)IMG_4027 (https://flic.kr/p/2pkpGeR) by emanookian (https://www.flickr.com/photos/8973550@N04/), on Flickr

https://live.staticflickr.com/65535/53384844824_a7cf0c0308_h.jpg (https://flic.kr/p/2pkrht3)IMG_4028 (https://flic.kr/p/2pkrht3) by emanookian (https://www.flickr.com/photos/8973550@N04/), on Flickr

https://live.staticflickr.com/65535/53384534566_08d3420241_h.jpg (https://flic.kr/p/2pkpGeL)IMG_4029 (https://flic.kr/p/2pkpGeL) by emanookian (https://www.flickr.com/photos/8973550@N04/), on Flickr

[FatMongo]

Aside from what youve covered above, any tips or tricks on fabbing up the crossmember for the Allroad chasis?

[FatMongo]

Thanks again for this phenomenal thread OP.

A couple other questions...

Did you use the 2.0 starter? Because the 2.7 01E starter will not bolt into the 02X. The 2.0 starter looks a bit smaller than the 2.7/01E. Have you experienced any issues?

Also, did you use the 02X spacer or backing plate at all?

[blairdude]

Aside from what youve covered above, any tips or tricks on fabbing up the crossmember for the Allroad chasis?

I'm currently working on some CAD files to reproduce the adapter brackets I made, and they are being designed so the undercoating does not need to be scraped off.


Thanks again for this phenomenal thread OP.

A couple other questions...

Did you use the 2.0 starter? Because the 2.7 01E starter will not bolt into the 02X. The 2.0 starter looks a bit smaller than the 2.7/01E. Have you experienced any issues?

Also, did you use the 02X spacer or backing plate at all?

I used a B7 TDI starter from Europe, along with the spacer plate from the same car as the transmission donor, however, whether or not you use a euro starter or the spacer plate depends on what clutch you use. I used a B7 TDI 240mm clutch which requires the spacer and the euro TDI starter. If using a 228mm clutch/flywheel you can use the BHW starter without a spacer. There's also an aftermarket 240mm single mass flywheel/clutch that's designed to be used with the BHW starter and no spacer.

The 2.0T gas starter will physically fit and might turn over a BHW enough to start, but it's probably too weak for cold starts in the winter.

Using the euro TDI starter also requires a turbo brace from a euro TDI w/240mm clutch, and the right engine mount bracket may need a bit of grinding to clear the battery cable, or a BPW right engine mount bracket can be used (what I did). I covered a bit about the starter above, as well as how I got a pilot bearing to protrude long enough to be used with the spacer.

I've got about 12,000 kms on my setup already, no issues, and the euro TDI DMF/clutch is super smooth.

[FatMongo]

I'm currently working on some CAD files to reproduce the adapter brackets I made, and they are being designed so the undercoating does not need to be scraped off.



I used a B7 TDI starter from Europe, along with the spacer plate from the same car as the transmission donor, however, whether or not you use a euro starter or the spacer plate depends on what clutch you use. I used a B7 TDI 240mm clutch which requires the spacer and the euro TDI starter. If using a 228mm clutch/flywheel you can use the BHW starter without a spacer. There's also an aftermarket 240mm single mass flywheel/clutch that's designed to be used with the BHW starter and no spacer.

The 2.0T gas starter will physically fit and might turn over a BHW enough to start, but it's probably too weak for cold starts in the winter.

Using the euro TDI starter also requires a turbo brace from a euro TDI w/240mm clutch, and the right engine mount bracket may need a bit of grinding to clear the battery cable, or a BPW right engine mount bracket can be used (what I did). I covered a bit about the starter above, as well as how I got a pilot bearing to protrude long enough to be used with the spacer.

I've got about 12,000 kms on my setup already, no issues, and the euro TDI DMF/clutch is super smooth.

Again, REALLY good info. However, I am a moron - turns out that the 2.7 starter will run just fine with the 02X. So I am good there, I will be using my 2.7 starter.

One thing I didnt think about is routing down pipes through/over the 02X crossmember. Since you are running a BHW, you will not have the same geometry as me who is going to be running a 2.7. On the FB groups pages, it looks like many of the B7 swap guys have an issues with exhaust with the 2.7 and 02X in the B7 chassis. I have no idea if the Allroad is more forgiving or not, but we'll see about that.

Do you have any rough dimensions available for your crossmember adapter plates?

[blairdude]

Again, REALLY good info. However, I am a moron - turns out that the 2.7 starter will run just fine with the 02X. So I am good there, I will be using my 2.7 starter.

One thing I didnt think about is routing down pipes through/over the 02X crossmember. Since you are running a BHW, you will not have the same geometry as me who is going to be running a 2.7. On the FB groups pages, it looks like many of the B7 swap guys have an issues with exhaust with the 2.7 and 02X in the B7 chassis. I have no idea if the Allroad is more forgiving or not, but we'll see about that.

Do you have any rough dimensions available for your crossmember adapter plates?

Ah you're just manual swapping a 2.7. Clutch/starter/bellhousing spacer should in that case be identical to using a 01E. I'm not 100% sure, but I believe the 2.7 manual cars use a thicker bellhousing spacer than the one you'll find on a 2.0L B7.

I'm still working out the exact measurements, so not 100% on some of them (prototyping in plastic right now), but the ideal thickness seems to be 18mm with a 9mm step (crossmember bolts mount on 2 planes on both sides). My first versions were just made with 3/4" flat bar which is close enough to fit pretty well but not 100%. If you bolt up the crossmember with the two subframe bolts, the crossmember will show you the shape of the brackets to be cut, and where to drill the holes. Make sure your subframe is aligned before starting this process.

As for exhaust, I have no idea what fitment is like, but it will probably be comparable to in a B7. The Passat BHW downpipe had zero issues clearing it though.

[FatMongo]

Ah you're just manual swapping a 2.7. Clutch/starter/bellhousing spacer should in that case be identical to using a 01E. I'm not 100% sure, but I believe the 2.7 manual cars use a thicker bellhousing spacer than the one you'll find on a 2.0L B7.

I'm still working out the exact measurements, so not 100% on some of them (prototyping in plastic right now), but the ideal thickness seems to be 18mm with a 9mm step (crossmember bolts mount on 2 planes on both sides). My first versions were just made with 3/4" flat bar which is close enough to fit pretty well but not 100%. If you bolt up the crossmember with the two subframe bolts, the crossmember will show you the shape of the brackets to be cut, and where to drill the holes. Make sure your subframe is aligned before starting this process.

As for exhaust, I have no idea what fitment is like, but it will probably be comparable to in a B7. The Passat BHW downpipe had zero issues clearing it though.

Not a manual swap. My Allroad is already a manual. I just cant stand the 4.375 geared Allroad with the .073 6th gear. It turns like 3500 rpm at 80 mph in 60th gear. Going with the 02X setup to make the highway driving more tolerable.

Again - THANKS for all the info!

[blairdude]

Not a manual swap. My Allroad is already a manual. I just cant stand the 4.375 geared Allroad with the .073 6th gear. It turns like 3500 rpm at 80 mph in 60th gear. Going with the 02X setup to make the highway driving more tolerable.

Again - THANKS for all the info!

Ah. In that case it should be fairly straightforward... you can reuse all the clutch hydraulics, all the clutch/spacer/starter stuff, BUT you'll need an auto driveshaft since the front section is shorter than the manual version. An A6 auto driveshaft can also be used by spacing the support bearing down about 25mm.

More on exhaust, I know the auto downpipes are shaped differently than the 01E downpipes for the 2.7. Do you know more specifically which ones have fitment issues on B7 swaps? Or is it both? Downpipe fitment should be roughly the same as in a B7, since the B7 front subframe is nearly identical, and the crossmember ends up in exactly the same place relative to the subframe and engine mount brackets.

[FatMongo]

Ah. In that case it should be fairly straightforward... you can reuse all the clutch hydraulics, all the clutch/spacer/starter stuff, BUT you'll need an auto driveshaft since the front section is shorter than the manual version. An A6 auto driveshaft can also be used by spacing the support bearing down about 25mm.


Dumb question... what do you mean by 'spacing the support bearing down'?

AS far as exhaust - Im not sure which downpipes guys were having issues. I was perusing the FB groups to plan for the crossmember solution for my 02X and I saw a bunch of B7 2.7 02X swapped guys complaining about DP clearance.

[blairdude]

Dumb question... what do you mean by 'spacing the support bearing down'?

On the Allroad, the driveshaft, like all other drivetrain components, is lowered 25mm relative to the body.

[FatMongo]

On the Allroad, the driveshaft, like all other drivetrain components, is lowered 25mm relative to the body.

Oh - duh! Makes perfect sense! THANK YOU!

[FatMongo]

So please understand, I make really slow progress. This is a long term project for me.

And just to reiterate - I have a 2.7 01E Allroad and all Im doing is swapping the 01E and stock Allroad diff (4.375 final drive) for an 02X and diff (3.89 final drive).

So based on what you said, I snagged a auto driveshaft from an 01 A6. The A6 driveshaft measure just about 65.25 inches.

Today, I had the 01E and 02X out and measured both. From the tail shaft to the edge of the bellhousing. For the 01E I got 33.25 inches and the 02X was right at 36 inches. Now granted, I havent compared the lengths of the differentials, so the difference might be made up there - but if I am going with a longer trans in the 02X, why am I also going with a longer D/S?

[blairdude]

So please understand, I make really slow progress. This is a long term project for me.

And just to reiterate - I have a 2.7 01E Allroad and all Im doing is swapping the 01E and stock Allroad diff (4.375 final drive) for an 02X and diff (3.89 final drive).

So based on what you said, I snagged a auto driveshaft from an 01 A6. The A6 driveshaft measure just about 65.25 inches.

Today, I had the 01E and 02X out and measured both. From the tail shaft to the edge of the bellhousing. For the 01E I got 33.25 inches and the 02X was right at 36 inches. Now granted, I havent compared the lengths of the differentials, so the difference might be made up there - but if I am going with a longer trans in the 02X, why am I also going with a longer D/S?

The auto driveshaft is shorter, not longer. Quoted from my earlier post, "you'll need an auto driveshaft since the front section is shorter than the manual version."

[FatMongo]

The auto driveshaft is shorter, not longer. Quoted from my earlier post, "you'll need an auto driveshaft since the front section is shorter than the manual version."

Thank you! Like I said before, Im an idiot - I didnt measure the OEM D/S.

This is such an awesome thread. So much amazing information.