What happens when you don't change your diff mounts, Center diff mount and....
09-26-2003, 01:04 PM
#33
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This is my CQ, all you questions answered here!
iThe car is a 90 early-build CQ. I have 221,000 miles on this beast. I've owned the car (or rather, it has 0WN3D me) for the last 4 years. The rear diff mounts (both the rear-most and side mounts) have been bad pretty much since day one. I have pics of those but not online yet.
The large crack featured in the first pic was the result of a recent accident where my car was struck directly on the passenger side rear wheel. Both the tie rod and the control arm were bent in the accident. The alignment was fine up to the accident and the tires did not show any unusual wear. Wheels: 16x7" cabriolet sport wheels. Tires 205/55-16. Suspension was stock but a bit tired. Car has never been airborne, at least not THAT airborne
The smaller rusty crack I believe is the result of having bad diff mounts and the subsequent years of driving with bad parts. The subframe bushings are in decent shape. They have minor small cracks in the rubber and are not distorted at all. Control arm bushings were also in good shape. The rear tie rods were good up to the accident. The ball joints had cracked boots but did not have excessive play and were still functional. Also note that this smaller crack is in close proximity to the larger crack, just on the upper side of the subframe. This weakness most likely made the larger crack possible in the accident.
"center diff mount" I'm not sure what this refers to as the center differential is part of the transmission. The transmission mounts should not have any effect on the rear subframe.
As for aluminum bushings and various other ways to prevent the damage...you will be transmitting more stress to the subframe than with a good rubber mount. However, a failed rubber mount allows a LOT of play and the famous "clunk" when releasing the clutch. The impact of diff torqing/clunking is greater than the minor vibratory stress you would experience with a more solid mount. In short, I would take the stock mount in good shape over the solid mount. Solid mounts will be noisier in the cabin, but they will also improve drivetrain efficiency.
I will not be welding this crack as the subframe is most likely bent/out of square from the accident. I will be replacing it with a good used SF from an 80Q. Most likely, I will be welding the seams on this subframe to prevent cracking on the new subframe.
My final point: I don't appreciate people using my pictures without permission. I mean, there's nothing I can do about it, but hey a little courtesy or credit (ie: I saw this on the 20v list) As for the moral of the story (change your mounts OR ELSE): are you qualified to make that assessment based on someone's car? Also it seems your post didn't include the most important information (the accident) so this is a bit misleading.
I hope this has shed some light on the situation!
The large crack featured in the first pic was the result of a recent accident where my car was struck directly on the passenger side rear wheel. Both the tie rod and the control arm were bent in the accident. The alignment was fine up to the accident and the tires did not show any unusual wear. Wheels: 16x7" cabriolet sport wheels. Tires 205/55-16. Suspension was stock but a bit tired. Car has never been airborne, at least not THAT airborne
The smaller rusty crack I believe is the result of having bad diff mounts and the subsequent years of driving with bad parts. The subframe bushings are in decent shape. They have minor small cracks in the rubber and are not distorted at all. Control arm bushings were also in good shape. The rear tie rods were good up to the accident. The ball joints had cracked boots but did not have excessive play and were still functional. Also note that this smaller crack is in close proximity to the larger crack, just on the upper side of the subframe. This weakness most likely made the larger crack possible in the accident.
"center diff mount" I'm not sure what this refers to as the center differential is part of the transmission. The transmission mounts should not have any effect on the rear subframe.
As for aluminum bushings and various other ways to prevent the damage...you will be transmitting more stress to the subframe than with a good rubber mount. However, a failed rubber mount allows a LOT of play and the famous "clunk" when releasing the clutch. The impact of diff torqing/clunking is greater than the minor vibratory stress you would experience with a more solid mount. In short, I would take the stock mount in good shape over the solid mount. Solid mounts will be noisier in the cabin, but they will also improve drivetrain efficiency.
I will not be welding this crack as the subframe is most likely bent/out of square from the accident. I will be replacing it with a good used SF from an 80Q. Most likely, I will be welding the seams on this subframe to prevent cracking on the new subframe.
My final point: I don't appreciate people using my pictures without permission. I mean, there's nothing I can do about it, but hey a little courtesy or credit (ie: I saw this on the 20v list) As for the moral of the story (change your mounts OR ELSE): are you qualified to make that assessment based on someone's car? Also it seems your post didn't include the most important information (the accident) so this is a bit misleading.
I hope this has shed some light on the situation!
09-26-2003, 03:17 PM
#37
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and I thought this was Audi panzerwagen 's own first hand experience...! very misleading panzer.
Yeah I had to compromise my morals (signing up for Audiworld) just to fix the misinformation. Thanks a lot bro!
(if you couldn't tell, this post is in jest)
(if you couldn't tell, this post is in jest)
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