'87 S4 Issues with Torque Tube
 

'87 S4 Auto

After removing the heat shields and fuel tank I'm now in the process of removing the rear suspension. Still following Dwayne's excellent write-up I started loosening and removing parts around the torque tube. It looks like this:

https://cimg1.ibsrv.net/gimg/rennlis...844e5308ed.jpg

As you can see on the left side of the above picture, I removed the bell housing. To my surprise I found this 'slush' inside:

https://cimg9.ibsrv.net/gimg/rennlis...e4d63cc5e8.jpg

https://cimg5.ibsrv.net/gimg/rennlis...29e2186367.jpg

It's a mixture of white and green stuff; has anyone ever come across the same problem? What could be the origin of the slush?


Also in Dwayne's write-up he mentions "heat reflective fire resistant material" around the ATF cooling lines, but that seems to be completely missing on my car. As I haven't been able to locate the heat resistant material in PET, is it supposed to be there?


One more issue I discovered was the tube were the e-brake cable exits the floorboard into the wheel well. Dwayne's picture shows a nice tube, but mine looks like this:

https://cimg6.ibsrv.net/gimg/rennlis...9c6ba64a1e.jpg

The stuff on the left with the white edge is the undercoating, but on the right is rusty metal. I'm thinking of cutting it back and somehow insert some pipe, maybe a copper pipe, to create a water tight socket for the cable. Anyone have another suggestion?


The rest is coming along fine: the transmission is secured to the sway bar. Hopefully tomorrow we can remove the final bolts and lower the suspension.

https://cimg0.ibsrv.net/gimg/rennlis...955b8ad797.jpg


Thanks again for any help, I really appreciate it...!!!!

Hi Manfred,


Could have been some coolant leaks from the coolant hoses that go into the heater core which are at the rear of the engine bay and above the engine. The same area where the heat valve lives.


By the way, did you put a flat edge against the flex plate yet? It might be bowed a bit to the front from the amount of splines showing toward the rear. This is a good check before loosening the pinch bolt of the front clamp to see if you had pressure on the crank thrust bearing from the rear.


Cheers,
Constantine

I concur with Constantine's observation about your flexplate clamp- it very much looks as though it has slipped by the typical 3mm so often seen. If you index the splines with a spot of white paint or correction fluid you can then see how far it moves when the pinch bolt is removed. that or take an initial measurement between the clamp and the end of the splined section.

Measurement of crank end float is essential to reference where the thrust bearing currently sits. No to reason to suspect anything untoward. If the flex plate has slipped by 3mm or so you will be well advised to take one of the recognised mitigations to prevent engine destruction by TBF.

Not sure what your general plans are at the moment but if nothing else it looks as though the entire drive line needs a good clean/refresh to get all the Dutch salt and associated road crap off everything.

Rgds

Fred

Rgds

Fred

Thanks for advice, Constantine and Fred. I will loosen the front clamp bolt and see what happens. My only concern is that I followed Dwanye's write-up quite accurately and already loosened the rear bolt that secures the drive shaft in the front of the torque converter. Will that jeopardize any result from loosening the front bolt? I will take measurements and loosen it anyway, just to gather the numbers....

General plan is to take both torque tube and transmission out, have the transmission overhauled and install Constantine's superbearings and eventually also the superclamp.
After completing everything at the back I also want to take the engine out to do the intake and replace fuel lines, gaskets etc.....

Manfred,

If you offer the rear pinch bolt and it does not want to re-engage then you will know that forward pressure has pushed something backwards or so I would think given there is a detente in the shaft at the rear position. Just looking at the rear bolt location using a torch should tell you this. If it is has not moved just slot the bolt back in and pinch lightly.

I trust you will be replacing the two torque converter bearings- they are a common wear point. If you intend to fit Constantine's excellent clamp now is a good time to do it when everything is out.

The drive shaft will resist movement to some extent but it does not take that much force to get it to move laterally as many have seemingly experienced [unexpectedly]. Be careful to support the tube when you undo the rear flange bolts to avoid undue stress on the drive shaft.

Your comment about replacing the transmission and then taking the engine out does not make too much sense to me. Surely it is better to pull the whole job lot at once to minimise total effort? Do you really need to pull the engine? If you intend to remove the cylinder heads then it makes sense but if not...?

Rgds

Fred

Hi Fred,

Thanks again for your comments. I´ve loosened the bolt on the clamp this afternoon and there was a slight movement: the 'threaded' part on the right side of the clamp measured 8.02mm before loosening, and 7.22mm afterwards:

https://cimg7.ibsrv.net/gimg/rennlis...fcbe80316c.jpg

I know it might not be the most logical sequence of doing stuff on the car, but it helps me keep everything 'under control'...:-). When everything at the back is done, then after puling the engine I can put the crossbar back in, lift the car and do the next jobs: front suspension, motor mounts and steering rack. Having the motor out gives me the space to do the intake and replace all fuel lines etc. Then put the car back down, crossbar out, engine in, and than hopefully see some light at the end of the tunnel....:-)

Today we finished removing the rear suspendion, went smooth apart from the speed sensors that wouldn't come out. All wiring was cracked and the insulation fell right off, so I'm still glad I chose to take my time but do it right....

https://cimg9.ibsrv.net/gimg/rennlis...1ffd788369.jpg

Thanks again Fred...!!!

Manfred,

Now that you have the rear end out you should check the upper control arm bushes for compression [they eventually take a permanent set increasing camber] and the camber adjustment for damage to the shoulder that the adjuster bolt rubs against. These two problem areas can result in lack of camber adjustment in the correct range depending on how far gone they are. I did both these items recently and now things are back under control.

You would also be wise to implement mitigations against the movement of the flex plate. Seems yours did not move much but the problem that many of us perceive is that once movement starts there is no predicting when it will go out of control and irreversibly damage the engine should the TBF syndrome occur.

Rgds

Fred

I will replace those, so hopefully that will take enable proper camber adjustment. Made a photo of all the parts I bought so far for the rear suspension:

https://cimg8.ibsrv.net/gimg/rennlis...e89ca2a93.jpeg

As for the mitigations you mention, what are the options besides the superclamp?

Manfred,

You are looking good for parts!

The clamp mitigation options range from the Superclamp, two auxiliary bolt on solutions- the PKlamp and the Ritech clamp, and then the cheapo option I have been using for the last 16 years- Loctite 290. There was also another solution proposed by Theo in your neck of the woods but I do not know what happened to that one or whether it ever got to market.

What do the camber adjuster shoulders look like?

Rgds

Fred

I understand the idea of camber adjustment, but can't figure out what the 'shoulder' is. I've been trying to find a picture on the net of where exactly the camber adjuster shoulder is, but can't find it.

Can you help me out Fred? Is it by any chance this 'socket' where the lower arm was attached with the eccentric bolt?

https://cimg9.ibsrv.net/gimg/rennlis...2b6038a4a.jpeg

Manfred,

That is exactly the point or so it seems. Your photo gives a clue that there is some bruising but it is not at all clear. Take a look at the thread I did a short while ago - link below.

https://rennlist.com/forums/928-foru...nt-pocket.html

The trick is to know at what point something needs to be done. My camber had reached a point where I could not get less than minus 1.5 degrees of camber, it was not a major problem for me but it was an annoyance.

Basically when the camber adjuster is in place it should sit flush with the shoulders on both sides but if the shoulder gets "bruised" as mine did [and apparently many do] one loses the range of adjustability. Add to that the effect of the squished upper arm bushes and it can become problematical. I suspect the damage was done by someone not torquing the bolt correctly.

Hopefully this will not be an issue for you but at least you will understand the possibilities.

Rgds

Fred

Use something non-metallic for the e-brake cable penetration. Otherwise you will end up with more corrosion due to the dissimilar metals.

Fred and Manfred
Do either of you have a list of items and part #s that should be replaced as preventive maintenance on the rear suspension. I am currently working on replacing items on the front suspension.

Roger at www.928srus.com would have such a list and is quick to ship. 817-430-2688

Awesome. Thanks