Do I Need A New Spindle Knuckle?

[arjun90]

After Much Effort, my Driver Side Pinch-bolt finally came out of the Spindle Knuckle. However, it took a lot of beating (from hammering with a punch, air hammering with chisel, angle grinder, and drilling using 1/4", 5/16", 3/16", and 3/8" bits)

Propane torch was not used as there was apprehension of damage to the aluminum material.

My points of concern are the rear upper control arm pinch bolt slot (you can see how it appears deformed after making accidental contact with an angle grinder) as well as the entry to the pinch bolt hole (where the head of the bolt is supposed to make contact with the spindle--front upper control arm side).

Here are pictures for reference. I would greatly appreciate your feedback on this matter. What do you all recommend? By the way, a new spindle costs a little over $350 from the dealer. And a used one is no where to be found for this particular make and model. Also, I feel I could have spared my upper control arms (the ball joints were stiff) if I had placed a metal sheet in the area.

http://s1088.photobucket.com/user/ar...ring%20Knuckle

[arjun90]

Pictures,

[Audibot]

Have you tried giving Auto Haas a call? They may have it in stock. https://www.facebook.com/AutoHaas or https://www.autohaasparts.com. Or Shokan?

Also, Genuine Audi Parts says it's the same from any A6 (2.7T or 3.0, but not allroad), so maybe you'll have more luck with that?

Part #: 4B3407253G

Also your local craigslist. IDK where in NY you are, but I found a few cars in NYC area, one of which is an 04 for parts.

[LINDW4LL]

It's likely fine, but if you want to replace anyway, these things are all over eBay for < $100 shipped.

[arjun90]

The only problem with what is available on eBay is that they are all steel uprights (mine is aluminum) and size-wise, the ones on eBay are slightly larger.

The Audi dealers confirmed my part number its unfortunate that I can't use anything other than that.

Sometimes Wolf Auto Parts carry them, but currently they're not in stock.

The area where the Grinder made contact is also concerning me, if you look at closely at the pictures, I'm not sure if the structural integrity has been compromised / weakened. The area still pinches the bolt as its supposed to, but I'm not sure if it has that same level of contact as before.

[julex]

Looks ok to me to be honest, I wouldn't replace it myself. I've seen far worse ones left in there after pinch bolt adventures.

And there are planty of aluminum ones on ebay, just search for "Audi a6 (upright, spindle)" and scroll through the pictures, you can clearly tell them apart. They will never be titled with "aluminum" in the search.

[Audibot]

The Audi dealers confirmed my part number its unfortunate that I can't use anything other than that.

And what part number would that be? Part of me thinks that's a load of crock...

[rollerton]

Looks ok to me to be honest, I wouldn't replace it myself. I've seen far worse ones left in there after pinch bolt adventures.
.

Yep. What he said. As horrible as it is, I'd consider it a success! Does it pinch? Yes. But when you tighten it don't go nuts. The pinch bolt doesn't have to be cranked down super hard to do it's job, it's just holding a ball-joint in place.

[arjun90]

I actually thought the grinder ate its way through a minute amount from the spindle (through the far right slot)

Will I be able to flatten the mushroomed area where the pinch bolt initially inserts to?

The part number I have from the dealer is 4B3-407-253-G

Manufacturer: Audi
Part Number: 4B3-407-253-G
Part: KNUCKLE, LEFT
Replaces: 4B3-407-253-D, 4B3-407-257-G
Part Notes: 2.7 & 3.0 LITER

And what part number would that be? Part of me thinks that's a load of crock...

[Audibot]

So... I'm slightly confused. Is this the driver's side or passenger's side? Your photobucket says Driver's side, but the part number is for the passenger side, which tells me more that the dealership has no idea what they're talking about.

The part number I gave you above, 4B3407253G, will work just fine (253 = Driver's side; 254 = passenger side). Also $350 from the dealer isn't bad considering GAP has it for $570 (MSRP $765), but as suggested above, you could probably drive on it fine. But for peace of mind, check your local (and slightly extended) craigslist. Or hit up the C5 forum on Facebook to see folks have.

[arjun90]

My mistake, its 4B3-407-253-G (Left Side--Driver Side)

Can't find matching part numbers on eBay though even through the older part numbers

So... I'm slightly confused. Is this the driver's side or passenger's side? Your photobucket says Driver's side, but the part number is for the passenger side, which tells me more that the dealership has no idea what they're talking about.

The part number I gave you above, 4B3407253G, will work just fine (253 = Driver's side; 254 = passenger side). Also $350 from the dealer isn't bad considering GAP has it for $570 (MSRP $765), but as suggested above, you could probably drive on it fine. But for peace of mind, check your local (and slightly extended) craigslist. Or hit up the C5 forum on Facebook to see folks have.

[julex]

search by original audi part# rarely works well on ebay and certainly not for used parts, only for new ones. Used parts are usually binned by hollander exchange # which has nothing to do with any specific car brand parts naming scheme. However, since I have ETKA, I can telly you that 4B3-407-253-G was used in the following cars circa 2000 IF the car had aluminum spindles:

1999-2001 S4
1998-2005 A6/Avant
1998-2005 A6/S6/Avant Quattro
2001-2002 RS4/Avant Quattro
2003-2006 RS6/Rs6 Avant/Quattro

So you see, audi was using the same exact part in all audis of that era if they had aluminum spindles, which is a performance part so that's why it initially was equipped to S4, RS4 and then RS6 and due to streamlining of supplies they also granted the honor to latter models of A6... and why if A6 is from 2003+ it is guranteed to have alu spindles. I know since I was hunting these to replace the awfully heavy iron ones in my allroad a year or so ago.

This means that any spindle that's made of aluminum and came from any of the cars listed above, will fit your car.

[arjun90]

Thanks julex, also thanks for assuring me the status of the current spindle on the driver side of my car. I think I'm overthinking here, and I should just use the the one currently on the car.
I sure did a lot of beating with hammer on with the upper control arms off and spindle resting on the axle and lower control arms. Do you all think I may have caused indirect damage to those components? I feel like I wouldn't know 'till I move the car again.

Also, out of curiosity though, if I ever need to replace the spindle (on either side of the car), what would I need to do to press out the bearing out of the wheel hub assembly on these models? Would a wheel bearing press kit work?

search by original audi part# rarely works well on ebay and certainly not for used parts, only for new ones. Used parts are usually binned by hollander exchange # which has nothing to do with any specific car brand parts naming scheme. However, since I have ETKA, I can telly you that 4B3-407-253-G was used in the following cars circa 2000 IF the car had aluminum spindles:

1999-2001 S4
1998-2005 A6/Avant
1998-2005 A6/S6/Avant Quattro
2001-2002 RS4/Avant Quattro
2003-2006 RS6/Rs6 Avant/Quattro

So you see, audi was using the same exact part in all audis of that era if they had aluminum spindles, which is a performance part so that's why it initially was equipped to S4, RS4 and then RS6 and due to streamlining of supplies they also granted the honor to latter models of A6... and why if A6 is from 2003+ it is guranteed to have alu spindles. I know since I was hunting these to replace the awfully heavy iron ones in my allroad a year or so ago.

This means that any spindle that's made of aluminum and came from any of the cars listed above, will fit your car.

[julex]

Thanks julex, also thanks for assuring me the status of the current spindle on the driver side of my car. Perhaps I'm overthinking here, and I should just use the one currently on the car.

Out of curiosity though, if I ever need to replace the spindle (on either side of the car), what would I need to do to press out the bearing out of the wheel hub assembly on these models?

These are easy since bearing cartridge simply bolts with 4 bolts onto the spindle, from the back. You still have to press the hub though but at least it is far easier to do with just bearing+hub needed to be removed for pressing out hub than to have to take out whole spindle to be able to press bearings out like you have to do with steel spindles.

[arjun90]

Thanks again julex,

Also, I sure did a lot of beating with hammer on with the upper control arms off and spindle resting on the axle and lower control arms. Do you all think I may have caused indirect damage to those components? I feel like I wouldn't know 'till I move the car again.

[Audibot]

FYI, I see a bunch on eBay that look right in the $100-$130 range. I searched knuckle vs spindle or upright. Some with wheel bearings, which as Julex mentioned, is held on by 4 bolts (triple squares). The hub is pressed into the bearing/bearing is pressed onto the hub.

If you do eventually decide to go that way, the hub has a tendency of rusting to the spindle along the perimeter, and may require some persuasion to come off.

[bpark1210]

They look fine. If a new bolt can slide through you're fine. The outside appearance of the bearing housing should be no concern, as long as you can get a new pinch bolt to go through and hold onto the CA ball joints it's doing it's job.

FYI . . . When I took an air hammer to punch out the control arm ball joints I accidently marred up the inside of the spindle. Since the S6 spindles are made of aluminum I just took a standard punch and hammer to knock down the marring until it was smooth again. So if you do run into bolt fitment issues look at repairing before commiting to buying a whole new spindle.

[rollerton]

They look fine. If a new bolt can slide through you're fine. The outside appearance of the bearing housing should be no concern, as long as you can get a new pinch bolt to go through and hold onto the CA ball joints it's doing it's job.

FYI . . . When I took an air hammer to punch out the control arm ball joints I accidently marred up the inside of the spindle. Since the S6 spindles are made of aluminum I just took a standard punch and hammer to knock down the marring until it was smooth again. So if you do run into bolt fitment issues look at repairing before commiting to buying a whole new spindle.

That's wreckless! Whats wrong with you? These are precision German Automobiles. Arjun is just going the extra mile and making things perfect, no need to risk life and limb with that horribly weakened part.

Just kidding. I'm just here for the show. There's absolutely no reason to replace that..but let him have his fun I guess.

[B5in]

IMO it's completely fine as-is

[arjun90]

Thanks a lot everyone. I'm going to proceed as you all recommended, and keep the spindle the way it is. Definitely looking forward to a much better ride.

With all the work that went into getting the pinch bolt out on the driver side, it has me wondering now what I should do for the passenger side. Definitely one thing at a time. I am going to keep lubricating the passenger side as much as possible in the meantime to avoid a similar experience I had with the driver side.

How do you all think I should approach the passenger side? I'd be relieved if the bolt just comes out on one go.

[julex]

Thanks a lot everyone. I'm going to proceed as you all recommended, and keep the spindle the way it is. Definitely looking forward to a much better ride.

With all the work that went into getting the pinch bolt out on the driver side, it has me wondering now what I should do for the passenger side. Definitely one thing at a time. I am going to keep lubricating the passenger side as much as possible in the meantime to avoid a similar experience I had with the driver side.

How do you all think I should approach the passenger side? I'd be relieved if the bolt just comes out on one go.

some ideas before you start:

http://www.passatworld.com/forums/vo...ew-method.html

And a mandatory video from bntley which shows you exactly how to get it out with an air hammer:

[glennda5id]

Thanks a lot everyone. I'm going to proceed as you all recommended, and keep the spindle the way it is. Definitely looking forward to a much better ride.

With all the work that went into getting the pinch bolt out on the driver side, it has me wondering now what I should do for the passenger side. Definitely one thing at a time. I am going to keep lubricating the passenger side as much as possible in the meantime to avoid a similar experience I had with the driver side.

How do you all think I should approach the passenger side? I'd be relieved if the bolt just comes out on one go.

Take it out and take it to a machine shop.

[Audibot]

Take it out and take it to a machine shop.

Even just taking it out and laying it on a bench to work on is MUCH better than doing it in the car. You'll have so much more leverage and better angles to remove the bolt. You may be able to get a good few strokes to shock it loose before attempting. Some penetrating fluid (Kroil is the best I've ever used) and see if you can air hammer it out (sometimes after starting to go, the penetrant will act as lubricant).

Best of luck!