Driveline Bind & Popping - 1998 Audi 1.8T Tip Quattro

[cheap_b5_a4]

Whilst trying to having a rusty 1972 BMW 2002 towed to my house, the Audi decided it wanted to ride on a flat bed too! While driving at around 60 mph, the car started feeling like it had a flat tire, so I pulled off the road. To my surprise, it wasn't the tire. Now, I experience a very feelable "pop" and bind when driving the car forward. It shakes the entire engine and car in both forward and reverse. Even when rolling in neutral off of the flatbed, the car driveline still bounded up.

• 105k miles
• No CELs
• ABS module is dead
• Engine idles and revs fine
• Only transmission fault code is: 00526 Brake light switch - 27-00 implausible signal
• No clicking that I have heard
• Did notice front CV does have a tear, have no inspected grease content or inspected it yet since this incident
• Have not changed differential oil
• Have not change ATX fluid
• Car has only been driven 33k/mi in 10 years

So, possible CVs? Wheel bearings? Or are we diving deep into the driveline?

I appreciate all of your thoughts.

[Seerlah]

Have someone roll it in neutral while the other is outside the car, and pinpoint where the noise is coming from.

[cheap_b5_a4]

Last night I was able to get under the car. It seems like it is the rear end that is binding up.

It appears one e-brakes did not release and was "seized" on the driver's side which prevented me from easily spinning the wheel. After using a punch to release the e-brake, both wheels will spin in one direction, but bind/fight each other in the other direction. Even after the e-brake release, it is still binding/popping and it is more evident when "turning".

My thoughts are the differential is not letting the wheels slip enough which is causing the binding/popping. I saw no signs of a fluid leak, but I'll check there and potentially hit up a yard for a new differential.

// Oh Lord, let me go back to fixing my BMWs.

[cheap_b5_a4]

After looking deeper in the car, it appears it a transfer case / center differential leak let all of the gear oil out which causes the binding/popping. Topping it off with new 75w90 appears to have eliminated all of the binding/popping and the car will run smooth at highway speeds.