2004-2007 Cadillac CTS-V Performance Mods Discussion, Clunk in Cadillac CTS-V Series Forum - 2004 - 2007; Could somebody point me to the thread where I could read about the clunk in the rear end or tell ...
- 05-15-13 12:12 AM #1Cadillac Owners Member
- Automobile(s): 2004 CTS v
- Join Date
- Apr 2013
Could somebody point me to the thread where I could read about the clunk in the
rear end or tell me what I need to be looking into doing to get rid of it. It Happens when I push clutch in sometimes at cruise or when I first give it a little right foot
thanks for the help ahead of time. Sorry it's a 04 had it for about a month with
about 28000 miles on it and I'm in love with it
- 05-15-13 05:24 AM #2Cadillac Owners Fanatic
- Join Date
- Dec 2012
You need new bushings. Probably motor mounts and trany too. Not a bad idea to spend the 7-$800 and get all the revshift stuff IMO. You can search that to get more info if nothing else.
- 05-20-13 10:54 PM #3
So is it 7-$800 just for the parts ?
- 05-21-13 07:06 AM #4
The clunk in the drivetrain comes from multiple sources. The largest part of the clunk comes from the limited slip clutch setup in the differential and is inherent in the design. This can be seen by turning the drive shaft by hand with the wheels in the air. The driveshaft can be rotated a quarter turn before the wheels begin to turn. Because of this, totaling eliminating the clunk is only possible by replacing the differential with a different design.
When new, this clunk is masked by other components in the drivetrain. The motor mounts are liquid-filled to soften (delay) the rotational torque to the spring-loaded dual mass flywheel. Both the transmission mount and driveshaft also serve to absorb (delay) some of the rotational torque. The differential is mounted with rubber to further mask the clunk.
So, if the clunk has reached annoying levels, the common fix is restore the various clunk cloaking devices (differential bushing, motor mounts, transmission mount, etc.) to "new" condition. The permanent fix is to install one of the aftermarket differential setups.
- 05-21-13 09:32 PM #5
So DarkMan with that being said is doing the bushings only a bandaid ?If or I should say when I do the bushing I would be doing the red rev shift ones also would that tighten up handling too ? I want to do things to the V slow over time just want to do the right things first as I want it to last don't want to add any power or anything like that till the weak parts are stronger
- 05-21-13 09:52 PM #6
When to install other upgraded bushings to improve handling would seem to be an independent decision other than the overlap in the process. For example, if you drop the cradle to upgrade cradle and/or control/trailing arm bushings, it would be a good idea to install a new differential bushing at the same time. But, you may not want to tolerate a bad differential bushing and the increased clunk it brings if the other upgrades are several month away.
- 05-21-13 10:47 PM #7
Just a FYI...I've replaced the MMs and trans mount with Revshift and have Delrin bushings for the cradle - I still have clunk and it is annoying. I have not replaced the differential bushing - mainly bc I might replace it altogether for a permanent fix but is costly, even for DIY.
- 05-23-13 10:23 PM #8
Your have a 2004. It has a very weak differential housing witch has probably been stressed to increase the lash between the ring and the pinion causing the clunk. Replace the differential with a new
3rd Gen ----- 15793756 or
4th Gen----- 25873498
Diff along with the other mods the guys recommend. The clunk should be a lot less noticeable.
Quick tip the SRX diff also works in our cars and seem to be a lot cheaper and stronger the then 1st & 2nd gen diffs. If you get this part # 19178781 GT4 G80 3.73 option and limited slip. You would just have to cut off about a inch off the pinion shaft and swap out the pinion input coupler with your old diff.
- 05-23-13 10:48 PM #9
- 05-24-13 08:47 PM #10
Sorry haven't been on for a little works been crazy thanks for all the info but some of this is like another
language and I want so much to be working on all this on my own
Now if you guys where to do this would you put the oem back in it after you did all the bushing or would
you upgrade the diff and if you would what would you upgrade too
So you know not trying to build the fast V very just want it to work the most I'm going to do then is a
Exhaust and hot rod around town some
- 05-24-13 11:05 PM #11
It is a matter of personal choice, but I would stick with the OEM differential unless and until I wanted to throw on some sticky tires (e.g. drag radials) and go drag racing. You can get by with OEM on the street by launching a little slower and not power shifting.
(I only have 407 rwhp and I don't have enough traction on asphalt streets for go full bore in 1st and 2nd gear anyway.)