Chalkboss

I have a 87 S4 with 89K miles. About 12K miles ago the TT was rebuilt, Constantine clamp installed, and new TC bearings and new GB trans lines.
All this was done under the PO's ownership. I drove it for about 1,000 miles and then began a rattle noise I have described before on this forum. The noise occurs only unloaded, that is in neutral and in park. It comes and goes, and gets pretty constant around a certain rpm. I put it up on the lift and looked at everything and see no obvious problems, pulled the rear pinch bolt (fine) and re-torqued. Put a long screwdriver up to the TC housing and noticed a slight vibration in the housing when the noise occurs. The noise is coming from the TC, I believe.

My guess is it's the rear flexplate rivets coming loose. I have searched but is there a way to pull the TC housing to get at this flexplate without pulling the trans and/or TT? I have not worked on this part of the car so I am new to this.

Seems most people pull everything to do WYAIT but it's already been done here and I don't want a bunch of extra work if not needed. I have been called a glutton for punishment, however.

Thanks

NC928S4

Not sure if this is your issue but my 89S4 has been making a "geiger counter" type noise when not under load and always as engine is turned off. It has slowly been been getting worse and also seems worse once warmed up. The sound comes and goes and only heard when not under load.

I have replaced TT, TC Carrier Bearings, examined flex plate, checked end play, new MM, new transmission mounts and tightened everything I could get a wrench on. I had been all over the under carriage with the stethoscope but I gave up searching for the cause and decided to wait for something to actually break.

Yesterday, I replaced the Alternator Ventilation Shroud because the original was cracked and hanging on with a single nut and it had been sitting on my bench for a few weeks. To my great surprise the "geiger counter" clicking noise is now essentially gone. It still makes a slight but muffled rattle/clicking when I turn off engine. I'm going to drive it hard for a few more days before I declare victory.

Hope this helps.

Chalkboss

I hope that simple fix works out for you. I have been all over the car multiple times and always come back to the TC. I hope someone chimes in with a method to pull it that involves the least amount of bloodletting. It's to the point where I need to just deal with it, when strangers ask what that noise is.

Dave H.

you have the TSB for the rivets?

Schocki

The tranny has to be removed to take the rivets out of the rear flexplate and replace them with bolts.
WYAIT means this should have been included in the TC bearing job while the tranny was out of the car. Sorry you have to remove the exhaust, drop the rear axle and remove the tranny one more time....

Chalkboss

Ok well I tried. Pull the trans it is. I have seen the TSB on this, someone here posted a scan of it earlier in the year. I think while I am in there I will also plan on doing the trans pump o-ring, as I have some slight leakage at the TC cover opening. Also I need to check that all the relevant TC bearings were replaced. For some reason I recall only seeing one bearing on the parts list of the service order.