Tomfun

Background:
I installed a sleepers short shift kit a few months ago and have been very happy with it as I like the feel and am able to get the shifter closer to me so its more comfortable. I originally installed the OEM version, however the issue this caused was that with the shifter now raised, the leather boot was quite tight - tight such that I could feel it tugging when shifting into 2nd or 4th gear. I decided, therefore, to switch to the billet version of the kit.

Spent some time last night installing the billet version and then took it out for a test drive. When I shift to 5th, I get quite a loud noise coming from the shifter area - its hard to describe but I guess I would describe it as sounding like something metal is in contact with something spinning (like a drive shaft)? Doesn't sound good at all. I can minimize the noise by pushing the shifter up and to the right more, although it doesn't completely go away. Directly related to speed and not RPM, no change with clutch engaged or not.

I tried to do some troubleshooting this morning and pulled the center console apart again. Since the only thing I changed was the shift lever I reverted back to the OEM version and went for a test drive with everything open. I don't really hear the same noise in 5th, however it does seem remarkably loud with the shift boots and center console removed - has anyone driven around like this in a C4? Is it always this loud or do I have some kind of bearing issue somewhere?

Anyways, when I reverted to the OEM style shift lever I notice that the OEM version of the kit has a slightly wider area that the two plates bolt to - I don't know if the billet versions narrower machining causes something to interfere down below, but I can't think of what would be interfering. In any case, I swapped back to be billet version again and drove with everything open again - its definitely better than before, but 5th is still loud. I put everything back together to see what it sounds like with the boot on and its still substantially louder than when I had the leather boot/OEM shifter.

Anyone know whats going on here? Could this be torque tube bearings? For those who have the swine reboot, do you notice an increase in noise?

Thanks,

Tom

dmaddox

Hello Tom,

I just did a Rothsport and fd forward/golden rod install, with the swine eleven boot, etc.. on first installing everything it was the other side for me......when in Reverse....the bottom of the shifter (wider than oem) hit the shift tunnel. . . just enough to ride on it. What might be happening is your shifter way over in 5th is using your shift tunnel as a sounding board, amplifying the rotational noise of your drive train. When in R and 5, do you see if the shifter/linkage is clear of the sides?

964Luftballoon

Hi Tom,

I have the sleepers kit with billet and swine11 set up on my c4. I'm having trouble understanding your description of loud. Would you mind taking a short video and posting? My car is coming off the lift tonight so if I have a moment i'll take and drive and try to understand what you''re hearing.

Sleepers

Hi Tom,
PM me and maybe I can help out.

Thank You,
Gary Castillo
Sleepers Speed Shop

Tomfun

Confirmed shifter is clear of the tunnel, however it appears that when in 5th there may be enough lateral force to create contact between the shifter side and the clamshell - I've added a shim between the billet shifter and the side plate which seems to have corrected the really loud noise in 5th. General noise persists however; I now suspect that this is unrelated to the billet shifter but rather a noise that was there before but masked by the additional noise deadening of the OEM leather shift boot. Has anyone driven their C4 around with the boot/center console off? Is it normal to hear quite a loud noise from the tunnel?

This is post shim, so the noise in 5th is better, but you should get the idea from this video. Apologies for the awful footage, didn't have anyone with me.

964Luftballoon

Thanks for the video. I went on a drive this weekend and tried to listen for the same type of sound. Unfortunately, with my primary and second delete it's loud so I didn't notice anything out of the ordinary. I specifically tried to listen for anything grinding when I went into 5th. I'm curious to see what Sleepers response as they asked you to reach out to them.

Tomfun

Update: I'm quite confident after shimming the shift lever this is not related to the short shift kit, but rather the removal of the leather shift boot and a bunch of sound damping from the OEM shifter has uncovered a different, more concerning problem. I'm going to flush the trans and diff over the next few days to see if that makes a difference in the noise, but in the absence of that correcting the problem does anyone know how to diagnose torque tube bearings? Anything else I should be looking at? CV joint boots all look good and intact.

Cheers,

Tom

9khil

hello Tom. Did you ever figure this out? I have two issues after installing FDM ssk: loud noise in 5th gear (probably same as yours) and a rattle noise which goes away if I hold the shifter lever. I haven’t had the time to open up and check though.

Tomfun

Not yet. For mine I have the following potential theories from easiest to solve to most difficult:
1) Wheel bearing failure
2) "Gunk" or something in the transmission that can be fixed with a solid fluid flush
3) Front differential gear or bearing failure
4) Torque tube bearing failure
5) G64 gear or bearing failure

I plan to address 1 and 2 later this year and will report back any progress.

Tom

9khil

did you get to it?

Tomfun

Not yet, I'm slow. Car is in a thousand pieces for a suspension overhaul but getting close to re-assembly. This included new wheel bearings so I'll see if that worked relatively soon and update this thread.

Cheers

Tom

9khil

i flushed my diff today and added new oil. Also adjusted shifter lever properly. The rattle sound I hear in all gears at certain rpms got worse somehow.

Also uncovered that my diff seal is leaking