Play in the drivetrain
07-15-2009, 04:11 PM
#11
Audiworld Junior Member
Thread Starter
Join Date: Oct 2008
Posts: 43
Likes: 0
Received 0 Likes
on
0 Posts
Update after some driving. The major thud is the back has been significantly reduced with the mounts listed in previous posts. There is however some bumping left in the drivetrain. It occurs when letting out the clutch and acclerating hard. Might be play in the driveshaft ujoints, transmission, differential, or subframe mounts - I don't know. I am giving up on trying to fix it. It is fixed to the point where it is not embarassing to drive.
Just a comment - my 87 325is BMW with 240K miles is much better made/designed than my 01 Audi A4 quatro 2.8L.
Just a comment - my 87 325is BMW with 240K miles is much better made/designed than my 01 Audi A4 quatro 2.8L.
07-15-2009, 06:47 PM
#12
AudiWorld Member
Join Date: Aug 2001
Location: Mississauga Ont
Posts: 13
Likes: 0
Received 0 Likes
on
0 Posts
You haven't solved anything! Changing a bunch of components in the hopes of getting lucky is all you've accomplished.
Sounds to me like there is to much play in the drivetrain. If you can put it up in the air this is easy to check. Leave it in gear and turn both rear tires in the same direction. Back and forth till all the "slop" is taken up. Specifically watch how much play there is between the inner cv and input shaft to the diff. Also between the axles and C.V's There should be very little in any of these. If it is a steady click that accelerates with the speed of the wheel it's probably a CV joint
Also if you have changed brake pads recently and went with cheap ones they can be the culprit too. The chinese crap usually isn't an exact match to original leading to excessive movement of the pad within the carrier. I just finished a POS BMW 325 that clunked at odd times because of the above.
Sounds to me like there is to much play in the drivetrain. If you can put it up in the air this is easy to check. Leave it in gear and turn both rear tires in the same direction. Back and forth till all the "slop" is taken up. Specifically watch how much play there is between the inner cv and input shaft to the diff. Also between the axles and C.V's There should be very little in any of these. If it is a steady click that accelerates with the speed of the wheel it's probably a CV joint
Also if you have changed brake pads recently and went with cheap ones they can be the culprit too. The chinese crap usually isn't an exact match to original leading to excessive movement of the pad within the carrier. I just finished a POS BMW 325 that clunked at odd times because of the above.
07-21-2009, 08:42 AM
#13
AudiWorld Member
Join Date: May 2009
Posts: 141
Likes: 0
Received 0 Likes
on
0 Posts
I agree with everything you said except this...
Also if you have changed brake pads recently and went with cheap ones they can be the culprit too. The chinese crap usually isn't an exact match to original leading to excessive movement of the pad within the carrier. I just finished a POS BMW 325 that clunked at odd times because of the above.
I don't know where that came from but I can guarantee "cheap brake pads" is not what is causing this.
I am in the same boat. Tranny mounts, poly rears, DTS, snub, etc....fukng clunk is still there. Like I said, I agree with the points you made that could be the reason such as checking for play in drive shaft and axles.
Has anyone changed out their center diff mount? I have heard of almost everything bein changed but that. I want to get a new one to see if anything changes but a damn new OE mount is $300 somethin dollars.
I got a buddy that says he has a used one in good shape and will send it to me (if he finds it), if it makes a shiit of difference I will let you guys know.
Also if you have changed brake pads recently and went with cheap ones they can be the culprit too. The chinese crap usually isn't an exact match to original leading to excessive movement of the pad within the carrier. I just finished a POS BMW 325 that clunked at odd times because of the above.
I am in the same boat. Tranny mounts, poly rears, DTS, snub, etc....fukng clunk is still there. Like I said, I agree with the points you made that could be the reason such as checking for play in drive shaft and axles.
Has anyone changed out their center diff mount? I have heard of almost everything bein changed but that. I want to get a new one to see if anything changes but a damn new OE mount is $300 somethin dollars.
I got a buddy that says he has a used one in good shape and will send it to me (if he finds it), if it makes a shiit of difference I will let you guys know.
09-07-2009, 01:48 AM
#15
AudiWorld Senior Member
Join Date: Nov 2006
Posts: 612
Likes: 0
Received 0 Likes
on
0 Posts
I have the exact same problem and found this....
I did everything you guys did by changing all my mounts and still have the anoying clunk. My friend works at an Audi dealer and told me that the center bearing mount goes bad due to the U-joint in the center going bad. If it has slop in it, it's junk. If that's not bad he said it has to be one of the CV joints on the ends. He said to check for slop. I also have an annoying noise coming from the driveshaft that is sort of like a bad wheel bearing.
Next thing would be to inspect everything which I still have to do. I think a custom one piece driveshaft would be cheaper and better then OEM.
Next thing would be to inspect everything which I still have to do. I think a custom one piece driveshaft would be cheaper and better then OEM.
09-14-2009, 09:26 PM
#16
AudiWorld Member
Join Date: May 2009
Posts: 141
Likes: 0
Received 0 Likes
on
0 Posts
I think the drive shaft U-joints are the culprit to this. I have to find out exactly where it's coming from before I go tearing into the shaft if possible. May not me able to pinpoint it w/o takin all the shields and **** off to see/hear the clunk while it's right there in front of your nose.
I hear this job is a real PITA. There has gotta be a thread on here about it.
I hear this job is a real PITA. There has gotta be a thread on here about it.
09-15-2009, 05:16 AM
#17
Audiworld Junior Member
Join Date: May 2009
Posts: 40
Likes: 0
Received 0 Likes
on
0 Posts
the shield come off very easy, 4 nuts hold it on. You can move the shield out without dropping the exhaust. As for rebuilding the driveshaft the rebuild kit is $400 from blauparts. Along with the normal tools you need a torch varius cutting wheels and dremel tools and a shop press. Along with a few hours of your time at the least, probably more like 6 hours. IMPORTANT when disassembling the driveshaft mark all pieces with lines to match them all back on assembly.
another option is get a used driveshaft about $150. unbolt the old and bolt in the new. And hope the used driveshaft lasts a while.
last option is get the "rear propeller shaft" from the dealer about $1200 and bolt out and in.
another option is get a used driveshaft about $150. unbolt the old and bolt in the new. And hope the used driveshaft lasts a while.
last option is get the "rear propeller shaft" from the dealer about $1200 and bolt out and in.
09-19-2009, 09:05 AM
#18
AudiWorld Member
Join Date: May 2009
Posts: 141
Likes: 0
Received 0 Likes
on
0 Posts
the shield come off very easy, 4 nuts hold it on. You can move the shield out without dropping the exhaust. As for rebuilding the driveshaft the rebuild kit is $400 from blauparts. Along with the normal tools you need a torch varius cutting wheels and dremel tools and a shop press. Along with a few hours of your time at the least, probably more like 6 hours. IMPORTANT when disassembling the driveshaft mark all pieces with lines to match them all back on assembly.
another option is get a used driveshaft about $150. unbolt the old and bolt in the new. And hope the used driveshaft lasts a while.
last option is get the "rear propeller shaft" from the dealer about $1200 and bolt out and in.
another option is get a used driveshaft about $150. unbolt the old and bolt in the new. And hope the used driveshaft lasts a while.
last option is get the "rear propeller shaft" from the dealer about $1200 and bolt out and in.
09-29-2009, 08:38 AM
#19
AudiWorld Member
Join Date: May 2009
Posts: 141
Likes: 0
Received 0 Likes
on
0 Posts
I was told by an Audi mech that it could also be the dual mass flywheel. If not that then its the CV joints in the drive shaft; yes there are CV joints in the drive shaft not U joints.
10-02-2009, 02:25 PM
#20
Audiworld Junior Member
Join Date: May 2006
Posts: 33
Likes: 0
Received 0 Likes
on
0 Posts
I have also been trying to find the source of the drivetrain looseness. I have not found any one thing causing the problem. My mounts are in good condition and no axle or driveshaft joints are loose, also the flywheel is single mass. I'm at 134,000 mi 1.8T 5speed.
For now I am considering that with the large number of rotating parts involved, trans with front and center diff, rear diff, all 4 axles and driveshaft, that there is a small amount of wear that has happened to all parts and added all together is making the noticeable looseness.
For now I am considering that with the large number of rotating parts involved, trans with front and center diff, rear diff, all 4 axles and driveshaft, that there is a small amount of wear that has happened to all parts and added all together is making the noticeable looseness.