Rear shift coupling replacement with new Delrin bushings w/ pics.
 

Decided to replace the rear shift coupling bushings this weekend and did some searching before I attempted it. I could not find any pics of this procedure and even checked the oracle of HOW TO DO THIS at http://dwaynesgarage.norcal928.org/ (great write ups for us Noobs- Thanks Dwayne!) If there are those that can add shortcuts and ways to make this process easier for others, please do add them to this post. Forgive me for my noob abilities to post pics and my first write up....

This would have been a disaster without the solid advise on this board from fellow rennlisters describing how to do this procedure and what to do if you break the set screw off. Key to this procedure before attempting to unscrew the set screw was heating the it for about 5 mins before trying to remove it.

Pic 1 Location of rear coupling above torque tube, near front of transmission.
Pic 2 Marked spline before disassembly for reassembly alignment.
Pic 3 Coupling after heating set screw (old coupling has melted away)
Pic 4 Old coupling and new boot before coupling replacement.
Pic 5 New boot and what was left of old boot.
Pic 6 New Delrin bushings on top vs. Porsche OEM in package.
Pic 7 Pushed the old center post out using this method. Now pushing the center post in with new bushings using a vise and sockets. (Thx SeanR!)
Pic 8 Disassembled coupling.
Pic 9 Assembly lube used.
Pic 10 Shot of the dreaded set screw intact.
Pic 11 New bushings installed on coupling.

At this point it was reassembled on to the shift rod. Some extra hands might be needed in adjusting the shift rod into the spline to align the shifter. Mine was too far over to the left even with the marker on the spline.

New boot goes on first and clips over a flange on the transmission side, insert the coupling and tighten the set screw with minimum blue thread locker (be nice to the next guy...)

Align and set the spline side with the shift rod. Tighten the spline bolt and nut. Now the fun part, getting the boot back over the coupling toward the front of the car (shift rod side) to attach to the shift rod flange.

Not as great as a Dwayne write up, but I hope it helps someone out!

A little wd40 works wonders for getting that boot back on.

Good point Fraggle. Thanks!

how'd it go?

Still need to get her back up on the ramps and adjust the shift linkage. I can tell alread that it shifts much smoother than before.

I will however remember your advise and carry a can of WD40 underneath with me. The boot is quite tight so it will need a squirt.

P.S. I forgot to mention that Roger got me the boot on a Saturday (his usual great service) and SeanR gave me the tip on extracting the bushing and rod trick. Thanks Guys!

Glad it worked out. :)

Good deal! I thought I was being sneaky and put the boot on when the transmission was out, with the new coupler in it, but then ended up about an inch short on clearance to get the bloody thing back in the car!

Nice one Alex.

Nicely done, Alex! I admit this talk of shift rods, coupling bushings, splines and shift flange boots is oddly intriguing because I have no clue what these things do. My hat's off to you, Alex, and the other brave souls that have worked on 5-speeds and lived to tell about it! I hope to some day (or year) work on my 5-speed and when I do, I'll be referencing your post, Alex. THANKS for sharing!!

Thanks for your help Roger, I appreciate the leg work you did to find a part on a Saturday, that you did not have in stock, yet still found one for me so I could finish!!!:thumbup:

Dwayne,
That's very kind and I appreciate it. Thank you for going the extra mile and setting up your website, taking pictures and writing up the whole process and making our lives (especially us Noobs) a little easier tackling each project. Your previous work inspired me to take the pictures and write down the process. :cheers:

Just wanted to say thanks for documenting this procedure. I tackled it over the weekend luckily everything went as I hoped (i.e. no stripped 4mm set screw).

Just wanted to say thanks for documenting this procedure. I tried it over the weekend unluckily nothign went as I hoped (stripped 4mm set screw, the boot was already pulled back and the bush is completely gone with the screw head already stripped, I think the PO tried and failed so he wedged something in there to make it 'good enough').
I sure hope I can drop the whole rear subframe without removing the clutch too.

https://cimg0.ibsrv.net/gimg/rennlis...9e7e8e15a4.jpg
The small Allen screw is difficult to remove. Had to use a heat gun as the Allen screw is sitting with Loctite in the coupler housing. I made a special hex screw which will be much easier to remove in the future.
Åke

Åke,

Are you selling those parts?

Cheers
Scott

Everyone I've dealt with that has bronze bushing rattled so bad the owners wanted them tossed in the trash.

Good to know since they do look pretty.

That is interesting, it is the first time I have done this kind of job of installing bronze bushings on a 928 but I have done similar jobs on several other cars without an issue.
The winter is here making it impossible to take the car for a test drive. When the spring is here I will come back to you guys with a report.
Åke

I finally replaced mine, I probably spent ~13 hours doing it all together.
I disconnected everything from the rear subframe except the two electrical on the transaxel and the parkingbrake and just lowered it down with the torque tube still on it. I had to pull the clutch to get to the top two bolts holding the torque tube at the front.
I bought a longer 8mm allen head bolt that doesn't counter-sink and ground a point on it to replace the factory 4mm one that was stuck.
I ended up grinding into the old coupling and then knocking it with an air hammer and it fell off the car.

I replaced mine front and rear with the 928motorsports ones. That front coupling is a nightmare in my opinion. I could hardly do the jam nut trickery with the torque tube laying on the ground. I had to sand some 17mm wrenches just to fit both on at the same time. I have no idea how they expect you to do that on the car, with the whole 2 inches of working room you have after contorting your hand up and around the torque tube with it installed. I maxed the forward adjustment on it and the stick still leans further back than the factory front cup.

But in the end, wow. I didn't know a 928 could have such a positive feeling shift.

No doubt a difficult install even with the engine out.

No doubt one of the best mods for the car, the shifting is phenomenal.

Anyone have part numbers for the bushings?

30 322 424 911P - $13.75 the pair and I have 40 sets in stock

Actually. What are thoughts on a graphite set as opposed to a poly, plastic or rubber type?

Look at this on eBay
https://rover.ebay.com/rover/0/0/0?m...2F273671791667

That is the exact same set we sell for 1/2 the price.- the bushes were always Poly not Delrin - a common mistake.
Just talked to the manufacturer and they are indeed Polygraphite.

Wowo --- Big thanks. Send a link? Ill take'm...

Jay,

Just call Roger. It is much easier and he'll get you rolling.

call 817 430 2688 or email at Roger@928srus.com

Awesome day! Stunning difference!

Some before and afters... An hour or so is all it took! Now for the front coupler/ball swivel... I have the heat sheild out already but I think I will drop the exhaust, replace the bolts, the cat manifold gaskets and work that way with more and best room to get at things.

One hint if I can pass it on - on replacement,,, placing the conical allen bolt in it hole and threading it until it is just touching the metal shaft from the tranny WITH the allen wrench in the long way to help give grip and leverage while tryingto line up the conical with its hole I think is the way to go. There is not a lot of visibility so feel works. If you can move it a little on the shaft, with it just tight, you will feel it land home and notice you can turn it in. That helped me. Jus sayn

Thanks Roger and ALL... Love this site, and this sweet machine! Still, a loooong ways to go...
https://cimg2.ibsrv.net/gimg/rennlis...fc64cddc65.jpg
From under on the passenger side. Easiest approach side, I think.
https://cimg2.ibsrv.net/gimg/rennlis...07b6cf922b.jpg
https://cimg5.ibsrv.net/gimg/rennlis...e69e9b240f.jpg
Thank you ALL!

JayPoorJay, thanks for the photos for reference. These pics combined with ALKada's helpful writeup and bushing kits from Roger will make my much more prepared for the job. Considering that both the GT and the S4 are in dire need of bushings, I should be good to go!

No worries JP... Take another look at my last post,,, I just added an edit... I think it can help take a lot of frustration out of the last steps. The allen hole in the conical screw is sooo deep that leaving the allen wrench or a socketed allen in IS a great way to get and keep a hold on things while you are working, repositioning and lining things all back up. Serves like a small handle of sorts,,, then you can slowly turn it in and if its not dead on, the cone grabs the hole and pulls things into shape. Helped me lots, its a strange angle AND leaving an allen in might also help you keep the bloody boot out of your work space (pinned back and down) until you get things in place too. After, when you yank the allen tool, the boot will release and at that you can pull it over the knuckles.

That's BTDT advice that will save considerable time and frustration for those like me who HBTDT (haven't been there done that ;) ). I can visualize what you're saying and it makes complete sense. Good tip.

I do hope so JP... If I can be of help,,, just wake the thread.
Good diggin

great work and congrats on putting this one behind you. certain it was an amazing transformation. cheers!

Thank you merch!!!
I have lots more questions and lots more work to do. That's for sure. I am anxious to dig in... Thanks to the help of the folks here...!

Jay, thanks for adding to the thread. It’s always satisfyingly that this helped someone out like Dwayne’s site did for me.
Cheers!

Tackled this over the weekend. My buddy's lift came in handy:
https://cimg2.ibsrv.net/gimg/rennlis...ec43c13ce7.jpg

Starting with the shifter in 1st, got the boot peeled back toward the rear with the help of some WD40. I'm so used to cheap domestic or Chinese rubber which would have completely deteriorated by now. This German rubber was still strong and pliable. Truly amazing that it has held up so long.
Put reference marks on the coupler and black shifter shaft, and loosened the collar. Got to the hex set pin, and after reading posts about some being a bitch to loosen, I tried my Taiwanese 4mm hex drive for less flex and better leverage. I recommend having one of these hex sockets on hand before diving in:
https://cimg7.ibsrv.net/gimg/rennlis...4c1900125e.jpg
...it worked like a charm. Set pin threads were snug, so in anticipation of it being hard to thread back into the hole, I loosened the pin to the point just before it came out. Pushed the trans. shaft back toward the trans, which allowed me to slide the coupler forward, off the trans shaft and slide the shift shaft off of the spline.
This is how much bushings were left :o :
https://cimg7.ibsrv.net/gimg/rennlis...8e9c9dba62.jpg
..which explained a lot.
Drove the pin out using a socket arrangement like AlKada, however placed the coupler on the vise anvil and hammered on the small socket & drove the pin down into the large socket.
Cleaned out the coupler bores. The new bushings wouldn't fit without binding. I sanded the edges slightly for a small taper. They pressed in after that. I used a socket with a smaller diameter than the coupler flange and tapped the bushing in. Then a quarter on the other bushing and a 1/4" drive extension thru the installed bushing to tap the second one in.
Tapped the pin back in, reinstalled the coupler and checked shift alignment (front to back). Reverse wasn't quite engaging, so I increased the gap on the spline by 1/8". When in neutral, the shifter was sitting a bit too far to the left for my liking, so I turned the shift shaft clockwise 1/4 turn and tightened. The shifter now sits just left of center when in neutral.
Shifter is now tight as new and shifting is smooth and positive. I've had this GT for 19 years and the shift action has never felt so smooth, snug and positive.
Thanks ALKada for the thread, JayPoorJay for the tips and Roger for the bushings!

Damn JP... Great writing, and pictures to boot. Yup, my coupler looked JUST like that! Toast. Amazing it worked at all.

Where can I get one ah them lifts, jealous over here, lol! Over the weekend I changed out the front cup as well. All and all the difference is stunning, but like some of you might have seen, I made a stupid mistake installing some "fancy" plugs in her and completely thru off the way she runs. Have a right set of Bosch plugs from Roger due to arrive tomorrow... Looking forward to feeling her out with these changes. The 928 kinda MAKES me drive faster than I ever have, lol...

For me, dropping everything possible worked best for the front pivot. Sheared and replaced every bolt on the exhaust where the cat meets down pipe, with new flange/gaskets at the seam (dreaming of a lift, lol).... Then used a strap to pop on the new cup (not so easy). Oh,,, counted turnouts to remove original pivot arm to learn that the new pivot arm was approx 3 to 4 threads longer than the original. Had to compensate for that. Things worked out ok I guess. One thing I don't know how to solve is HOW to get the lock or capture nut that locks the arm to the rod JUST RIGHT before putting everything back together. Hindsight I'm thinking maybe a crowfoot wrench on a socket extension,,, putting it bad loose and tightening after,,, might be worth a shot. I think the stick could sit better than it is but i dont have the energy to go nack in just now. Anyways

Edit --- forgot to mention, for more movement in the rod that the pivot arm threads into,,, I unclipped and disconnected it from the stick inside of the car. This,,, with the TT still in place, I think, made this job a LOT easier. Jus sayn

Loooooong ways to go with time to get there. Thank you everyone for all your guidance.

https://cimg4.ibsrv.net/gimg/rennlis...4807ffee89.jpg
Above torq tube with pivot arm removed.
https://cimg2.ibsrv.net/gimg/rennlis...d9559ecbda.jpg
Everything out of the way.
https://cimg9.ibsrv.net/gimg/rennlis...54bc9587e2.jpg
2, 3, 4 threads difference.

Some one has already been there, snapped an allen key, and left the boot exposing the coupling

I presume this means there's nothing I can do without dropping the transmission

https://cimg6.ibsrv.net/gimg/rennlis...8e124b47ed.jpg

Fortunately there is not as much play as I expected, but it is still disappointing

Must have happened over 17 years ago, since that is how long I've owned the car

Out of interest, what is the 'exhaust hanger' for here?

https://cimg3.ibsrv.net/gimg/rennlis...a5c691ab79.jpg

I've never had to remove the exhaust before, and I will never try to do so again without having a couple of dollys to hand

Luckily I was above to borrow these from the office

Thankfully no one is using the parking space next to me, otherwise this would have been very awkward

https://cimg1.ibsrv.net/gimg/rennlis...c87fa775a0.jpg

A right angle drill and some stubby drill bits might fit up in that grub screw without having to drop the transmission (?)

I wouldn't even consider dropping the transmission until a valiant attempt was made to get that allen key bit out. Try with some wd, some picks, magnet and and and. Drilling first will really change the shape of the sheared allen remnant pinning it to the surrounding grub screw - also hardened, I think... Allen's are hardened steel and the way they break (usually) is a brittle shattering kind of break,,, not a break that twists the remnant into the surrounding metal - tightly. It's a tough spot to be in no matter what ---- luckily,,, the coupler doesn't looks so bad!

Then, there is removing the front cup, and undoing the shifter in the console which should allow you to twist the rod some to have it facing down at you. A better angle... That last idea is guess, never done it.

The hanger I think is for an exahaust of a different design. I have it as well - but my exhaust doesn't split in the same way as yours.

All of this is labor of love.

You might also just cut off and destroy the boot (or push it waaaaay back),,, spend a couple of Dremel bits and slice into the sides of the coupler - in place - and pry the halves away from each other. I think the coupler body will cut easily. At least loosen how tight it is on the tranny shifter shaft... Pry it off...

If I couldn't get the remnant out - picking - that would be my next approach. But that's just me. I can be a little rough around the edges, lol

Yup - labor O love

That hanger is part of the mid-exhaust hanger. Really helps the longevity of the hangers at the back of the resonators.
You want it.
I was able to source good used parts from 928 International for the Red Witch. Being in the UK, that might not be a financially sound idea.

Look at this screen shot from AutoAtlanta:

https://cimg6.ibsrv.net/gimg/rennlis...0c46b0a412.jpg



Good Luck!

The exhaust hanger was fitted on earlier S4's with the larger heavier resonators.

2nd job - not so smooth...
 

I decided to finally tackle the '88's failed coupler bushing. Not having access to a lift this go-round, I found that 4 jack stands at highest setting gave me enough wiggle room. A head-mounted LED freed up my hands.
The boot pulled back with a bit of fiddling, I unbolted the clamp and went after the set screw. I didn't see much crud or corrosion so I figured that the screw would come out as easily as the GT's did. I didn't spray it down with penetrating oil. Bad assessment.
Initially I tried a 4mm hex that was part of a multi-tool. Way too much flex. I found my hex ratchet drive set. As the ratchet with the hex drive finally started to turn, I thought that the set screw had broken loose. In fact the hex bit/socket was turning inside the hex bore. The hex bore was now stripped/rounded.
So now two options after the expletives: get the set screw out somehow or get the car off the stands and to a lift or to someone who could get the screw out. I figured one last ditch attempt: easy out/extractor. No room for a drill, but maybe with a little dexterity & patience.....
I happened to have a set of Speedouts in my toolbox. Those things have saved my ass more than once...it was worth a shot, and this time they came through.
The #2 surprisingly bit into the rounded hex bore and I was able to get a firm grip on the Speedout bit and managed to break the set screw loose.
Now I just need to replace the bushings and source a new coupler set screw (Roger, do you have these?) and I'm good to go.
Before crawling under your car to do this job, aside from having the bushings and a 4mm hex socket on hand, I strongly suggest:

• spraying penetrating oil into the hex pin recess at least an hour or so before starting work..maybe a little concentrated heat
• having a replacement set screw on hand in case the original gets stripped
• having a #2 Speedout as an extractor on hand and a box wrench, vise grips or adjustable wrench to turn it in case the set pin gets stripped

https://cimg0.ibsrv.net/gimg/rennlis...a5f6c1b5dd.jpg

Good good good, damn good, work.... I know how tough it can git under there...

That thing looks brand new!!! Lol...

Thanks for the write-up and tips! Love the community around 928s!
This doesn't seem like that hard a job after rebuilding cv joints, and I'm all bout shifter feel so even though my bushings are still there I'm sure they are tired, and I don't feel like I've spent enough time under the middle of my car yet!
What is consensus (ha!) - is the boot worth the effort to install?

I'd ask the pros here who can do the coupling replacements in their sleep -

• how these boots hold up - or don't hold up over time;
• whether or not it's actually needed if you're not a purist insisting on originality & the car isn't going to be driven in harsh environments;
• how hard it is to replace while you're in there....

Were mine so equipped, I'd be sorely tempted to fill the boot with grease and let it protect the grub screws and lubricate the bushings ongoing. I guess the boot would have to be installed for that to work.

Difficult to install. The only really good thing about the boot is that if the main bushing pin works its way out of the bushing, the rubber boot will keep it from falling out.
In California, we only replace the boot if the car is all original and the owner is trying to keep it that way.

Professional tip:
Never use the 928 424 229 00 tapered pin to attach coupler to transmission shift shaft. This pin needs to be tightened too much to keep it from backing out.
Use the 901 424 229 00 tapered pin, instead. It is exactly the same, except it has a nylon insert in the threaded portion to keep it tight. No need to over tighten. Will not work loose.

..and there are two replies that you can take to the bank.

I have been out test driving the blue Strosek car. My own modified rear shifter coupler with bronze bushings, the short throw aluminum shifter and the front metal shifter ball cup I fabricated myself are working terrific. Very tight, very precise shifting.
Åke
https://cimg4.ibsrv.net/gimg/rennlis...84d04982f5.jpg

https://cimg6.ibsrv.net/gimg/rennlis...0c07fa987a.jpg
https://cimg0.ibsrv.net/gimg/rennlis...5b31ad56ff.jpg
https://cimg3.ibsrv.net/gimg/rennlis...42c23b414f.jpg
https://cimg9.ibsrv.net/gimg/rennlis...aeb8ebe5bb.jpg

Beautiful! Does that drop into the stock shift rods? Impressive! And no more need for those plastic bushing inserts in the shift lever!

PS what's up with that period-correct phone?

Yes, it is made to fit the stock shifter rods. If the shifter wear with time bronze bushings can be installed. The phone holder including a Nokia phone came with the car when I bought it in the year of 2000.
Åke
https://cimg1.ibsrv.net/gimg/rennlis...e0a6f3b374.jpg

Pic 6
 

I didn't notice if anyone points out but when you're driving the pin out make sure that the receiving socket is inside the aluminum housing and up against the square part of the spline shaft. I blew my first coupler apart by putting the socket on the aluminum housing. Scary moment