Marc,

I'm right behind you buddy. Great stuff you are posting. Got my front half-shafts out today and tried refilling my front diff with a cheap pump from underneath. Bad idea. POS pump. Funnel and tube is the way to go and I am going to copy your setup tomorrow. I also need to get a gear puller tomorrow to pop off the the inner race of the CV joint.

 

Keep up the good work posting on the front CV's, Ricardo - I'll probably be doing that later over the winter too so I'll certainly be referring back to your thread.

Marc

 

I managed to make more progress today.

First, I replaced the front shift rod to change the ball cups and I also changed and greased three of the four shifter bushings.

This is all done from the underside of the car.....remove the central metal transmission cover (10 small nuts). Peel the large rubber boot of the underside of the shifter mechanism.

Then use a 19 mm open wrench to pry the ball of the front shift rod off the ball that is under the shift lever. You can then wrestle the front shift rod out of the end of the rubber boot and pry it off the front ball just by pulling down gently. This allows you to remove the front shift rod totally.




New and old front shift rods with ball cups. Yes, the cups can be bought cheaper than a whole new rod but the new one is so nice and shiny!





Rear ball cup (the one we pried off the shift lever ball first).




Front ball cup - I used a stainless hex nut as a jam nut to set the new rod the exactly the same length as the old rod (changing this length affects where your shift lever sits). Here the jam nut is not secured yet - use copper paste to ward off rust as these threads are exposed.




I bought a new rubber boot as mine was a bit dried out.




Slip the new rubber boot over the end of the front shift rod and then pop the new shift rod front cup over the ball welded to the front. Pictures show using a vice to pop these back together but that only works in a C2 as the C2 has a removable bracket the front ball is welded to - in a C4, the ball is welded to the torque tube. I used a small bottle jack to cram the two together with lots of fresh grease.




New and old boots attached. Can't have too many rubbers around!




Then pop the circlip off the end of the shifter shaft and remove the 3 washers (1 wavy sandwiched between 2 flat) and slip the rear shift rod off the shaft. I debating buying a new rear shift rod but they are $710 so I decided against and just cleaned up the one I had as best I could. There are also 2 of the 3 bushings I changed here.




I did spring for a new rear boot though.




The bare shaft - I then removed the circlip on the horizontal pivot shaft (3 washers as before) and removed the accessible bushing there too. The bushing on the opposite side I could not easily remove without removing the shift lever from above so I did not bother but rather just cleaned and greased the 4th one as best I could.




New and old bushings.




Here we are with two (one on horizontal shaft & one above the rear shift rod) new bushings in place with lots of grease and the rear shift rod re-attached - all that is left to do is slip the fourth new bushing on the end of the shift lever shaft below the rear shift rod end and slip the 3 washers and circlip back on. Finally we cram the new rear cup onto the shift lever ball with a big set of Channel-Locks and we are almost done.




Slip the rubber boot back around everything to keep it clean and we are done and ready for the transmission cover to go back on.


Parts used today were:

Front ball cup: 928.424.005.01
Front shift rod: 964.424.011.01
Jam nut: stainless M10 x 1.5
Front boot: 964.424.292.02
Rear boot: 964.424.294.03
Bushings: 999.924.002.40 x 4

Not replaced was the rear shift rod: 964.424.020.06


Marc

 

I also changed the transmission mount.




The rear anti-sway bar is a bit in the way so, since I was going to change the bushings on it anyway and I did not want to fight it - I just removed it.




Now we can get at the transmission mount that sits at the front right of the transmission case (different than a C2, of course).




Support the weight of the transmission - I used a 2x6 board across my lift, a small 2-ton bottle jack, and a rubber jack pad. I actually adjusted the height so I could easily slip the sideways bolt out so I knew the mount was not bearing any weight and the bolts and nuts would all line up nicely for re-assembly.




Undo the 3 nuts attaching the mount to the transmission (pictures a little out of order as no transmission support jack is seen here).




Undo the 6 bolts holding the cross-member piece to the body (it gets in the way of removing the mount and has to go) and undo the single bolt that holds the mount to the cross-member.




Cross-member off and old mount out.




Old mount out - looks tired but not cracked anywhere.




Clean up the bolts sticking out of the transmission, put on fresh copper paste and then install the shiny new mount with the three nuts and washers. Then re-attach the cross-member to the body using the 6 bolts and washers and slip the bolt through the bracket on the cross-member and the mount (I used a new bolt here as this single bolt actually holds the entire transmission so I did not want it to fail - plus a new single use lock nut). Breath a sign of relief because, now if your jack fails, your transmission won't fall and crush you.





Put a bit of copper paste on the cross-member - to - bracket bolt and tighten everything up then remove the bottle jack support. I could only find torque specs for the cross-member to body bolts (34 ft-lbs) so did all the nuts and bolts that tight -- anyone know differently??


Parts for this session:

Transmission mount: 964.375.023.01
M10x100 (8.8) cross-member to mount bolt: 900.074.292.02
Lock nut for that bolt: 900.910.292.02


Marc
(a transmission mount that can easily be changed with engine and tranny in place - just one of the many ways a C4 is superior to a C2 )

 

great progress... and fun to watch

 

I thought you changed for a solid transmission mount?
Did you ever do any of the diff slave cylinders? My lateral started leaking.

 

No - so far mine are fine.

Marc

 

Thanks.

Marc

 

Awesome Marc, keep it going, you are giving me confidence to keep tackling more and more.

 

Is there a difference in "shifting-feeling" or precision of shifting after changing the bushings.?

thx

 

Love this thread

 

Okay so a bit more progress this weekend.

I managed to change the fluid in the transmission.






Loosen the fill plug with a 10 mm hex driver to ensure it is not stuck.




Get ready to catch to fluid coming out then remove the drain plug with the same driver.



Drain all the old fluid out - remove the fill plug now too to help the fluid drain better. Impressive colour, eh? (Redline Lightweight Shockproof gear oil). My transmission was just rebuilt 2 months ago so this fluid is not old but I wanted to change it to remove any grit from the new synchro's meshing etc. (like changing the oil after an engine rebuild).




Refill is the same as for the front. Re-install the drain plug with a new crush washer and torque to 22 ft-lbs. Slip the tube into the fill hole and pour in the new oil until it leaks out the fill plug hole. Access is through the left rear wheelwell.




I used Redline 75W90NS same as in the front. We need about 4 quarts.




Once it starts coming out the fill hole, put the fill plug back in with a new crush washer and torque to 22 ft-lbs. as well.



Parts used here: Redline 75W90NS (need 4 quarts)
Crush washers: 900.123.111.30 or 900.123.118.30 (same as oil crush washers)

If you want to change the plugs so they are shiny: 999.063.008.02 and 900.219.001.30

Marc

 

Thanks, guys.

Marc

 

I don't know as I've not replaced them before and I won't be driving the car for the next few months to try it out (snow) but I read a few threads saying that the shift "feel" can be helped, especially if bushings are worn (or worse, broken).

Marc

 

I also got a 993 steering rack brace installed.

Porsche issued a TSB #9604 (pages 1 and 2) regarding retrofitting 18" wheels to 1995/1996 993's. The steering brace can also be fitted to 964's, especially if 18" wheels are to be used (I run 18" MY02 wheels at the track) but this is not Porsche approved.

Regardless, I figured the extra bracing would not hurt. I read here before, however, that the brace will not fit on a 964 with power steering due to the extra lines (only on a manual steering RSA or a 993). That turned out to be wrong....

Truth is, with a little gentle power steering line bending, the brace fits just fine.




Here is the front power steering rack (looking upwards and backwards). Just need to remove the 2 hex head bolts holding the front of the rack in place.




Here is the brace along with the new bolts to hold it in place. The old bolts were 60 mm while the new ones need to be 80 mm to allow for the thickness of the brace itself. I used grade 8.8 bolts for safety and I think the old ones were of this grade too. Just wiggle the brace in place, copper paste grease up the threads and install the new bolts. Tighten to 32 ft-lbs.




I also replaced the two other allen head bolts holding the rear of the rack too as the TSB suggested. Here I used M8 x 60 grade 8.8 bolts with more copper paste on the threads. Tighten to 32 ft-lbs again.


Parts used for this:

Steering brace: 993.347.131.02
Front bolts: M8 x 80 (grade 8.8) x 2
Rear bolts: M8 x 60 (grade 8.8) x 2

Marc