tifosiman

Thanks Eivind for that info! Interesting that you had a ROW trans and you still had the same issue.

StoogeMoe-that's good info to add as well. Do you guys think I should start a separate thread just asking for info on trans failures, so it gets more exposure?

Andy, yep, I checked the numbers, it is an ROW trans that is in there now, the one that recently blew was not.

Joseph, it will run around $700 plus shipping, which is a deal if you price out a new r&p from Porsche.

I had a good discussion yesterday with Danny from P3 (the place that did the alignment and other work on my car in the past year............ www.p3automotive.com ). Danny has been working on 944's forever and has owned many, including his current 944 track car. His theory on 944 trans failures is this:

"Which came first the chicken or the egg?

The last one that we had here was the result of the rubber centered clutch disc falling apart and allowing the drive shaft to bang back and forth, at least that is what I came up with and I am fairly sure I'm right. Seeing how the rubber disc failure is such a prolific problem, I'd say there is a good chance that the majority of the 944's on the road have had this problem at least once in there life. Most people don't even know the disc is bad until a mechanic points it out to them, or you'll get the guy that comes in because he wants to know "what is
this clunk that I hear when I am leaving a stop light?", or "what is this horrible vibration in the shifter at certain rpm's?". some 944's could have had 3-4 clutch replacements by the mid 90's which was long before there were internet forums for people to share info about the common problems they have with their cars so it was harder for owners to know what to look for. So the bottom line is, all the transmissions you have purchased have probably seen the same abuses. I don't think there was problem with the metallurgy in the ring and pinion, just age and abuse. Also as far as auto crossing goes, I believe that to be much harder on the drivetrain than road racing with the lower gears used and harder shifting, so much time spent in the 1st-3rd range, third might be a stretch. I just think auto crossing is hard on the equipment. "

So now we have another theory to add to the mix. If Danny is correct, a stock r&p, installed correctly in a rebuilt trans with a good clutch and good driving techniques should last, until autocross is thrown into the equation.

Sorry to drone on endlessly about this................

Scott at Team Harco

OK - don't know if you started a different thread to compile your data. Here is my info.

Here's the short story:
85.5
164,000 miles
No LSD
Not autocrossed
Broke while accelerating hard in first or second gear out of a turn at an intersection.

Here's the long story:
Purchased the car in the spring of 2000 ($1000)
Spent all of the first year "restoring" the car to drivable condition.
Did all of the following things before taking it for a "shake down" drive to the local car wash (see last item listed in the short story):
Engine oil/ filter, fuel filter, K & N air filter, caliper rebuild/ pads/ rotors/ master cylinder, timing belt/ roller kit, waterpump/ thermostat, distributor cap/ rotor, spark plugs, clutch master/ slave cylinder, sway bar bushings (front), Koni shocks, front wheel bearings, battery, alternator/ starter rebuild and various cosmetic and lighting repairs.

I drained the transaxle during this period and less than one quart of lube came out. That which did come out had a definite metallic appearance to it. I knew this was going to bite me eventually. I filled the trans with Mobil 1 gear lube and hoped for the best.

With all the work done to this point, I felt the car was ready to be tested. I wanted to get it cleaned up a little before driving on a regular basis. So on the way to the car wash I got on the gas and proceeded to strip 6 teeth off the pinion!

The next few months were spent disassembling the trans - determining the damage and formulating a plan to repair it. After phoning around and gathering information on having the work done by someone else, or buying a used replacement, I decided the only way I could afford it was to rebuild it myself. I ordered a ring and pinion from Vertex ($470).

In my research, I read that clutch problems can lead to transmission damage on these cars (not that it can't happen to other cars as well). The clutch was always on the "to do" list anyway - so now was the time to do that. Afterall, the transaxle was out!

So, now I'm elbow deep in the trans rebuild. All went well, but it took a lot of time and effort. It is a very satisfying feeling once you get it all back together and it all works.
I bugged the guys at Munk's (Porsche repair shop) near me about every week. They were kind enough to let me photocopy the portion of the shop manual that I needed for the rebuild (~$25 "rental" and copy costs)
The other parts I needed came from the dealer. Total cost about $55 for axle seals, bolts and bearing shims. I used AMSOIL synthetic gear lube to fill the box when done.

The clutch job added these additional costs (everything from Vertex, except flywheel resurfacing):
Clutch, pressure plate, release bearing ($430)
Pressure plate bolts ($15)
Clutch release lever bearings ($20)
Flywheel resurface ($37)
Rear main seal (engine) ($15)
Pilot bearing (in crank) ($13)

Total for clutch job: $530 (parts only, labor free)

My receipts stop at the end of November of 2001. I remember getting some driving in before the winter hit. So it had to be for a short period in December of that year (then the DME crapped out on me).

Anyway - all is well. The car has been relatively trouble free since then.

Jeremy,
Glad to see you are going to take the plunge and rebuild yourself. Let me know if you have any questions I might be able to help you with. Experience is a great thing to draw from.

Attached is a picture of the trans with the new ring and pinion but not fully assembled.
Will attempt to post a picture of the broken gears if I can locate it....

jcheng

With respect to shock trashing the r&p, has anyone used the Redline "Shockproof" gear oil instead
of the regular 75W90 stuff? It's supposed to "cushion" the shock via a suspension of microscopic
particles. I seem to remember that this stuff was used by the 3000GT VR4 crowd. (The VR4
has a notoriously weak tranny).

--John

tifosiman

Thanks Scott for the reply. I printed out all of the pages from the manual pertaining to the trans rebuild process. Were you able to find all of the VW tools that the manual calls for? Did you use a transmission stand? Do you have a press at home or did you take the parts to a local shop?

And, finally, a lot of the steps involve heating the gears to specific temps before re-install. Did you do that with your home oven (Renee will love that ), or did you use another method?

Sam Lin

With fits like those, you need to heat for the parts to be installed or removed without damaging the shaft.

John, I run Redline Shockproof on the track and have seen it work miracles in a few race cases. I think it'd be an excellent choice here and would likely make a noticable difference in tranny life. However, the thicker Shockproof will cause some power loss through fluid friction.

Sam

Scott at Team Harco

OK. One step at a time. I did not look for or use any specific VW or Porsche tools. I do have some special tools that I have used in the past (Miller Tools for my Mitsus) to press in bearings over a long shaft. These worked just as well on the Porsche (Audi) gear box. Standard bearing pullers, snap ring pliers, etc will get you most of the way through this job. Having a well stocked press is very important. I did not use a stand either.

I did most of the heavy work at my old college (Lawrence Tech), in their fabrication lab. Lots of large work benches, big vices (not yet bad habits), presses and heat. Speaking of heat, we used an oven in one of the materials labs. It's a lot better than stinking-up the home oven with baked gear lube. If you have no other alternative, a home oven will work just fine.

If I had to do this again, I now have a press at home in the garage. Harbor Freight has great deals on things like this. I got my 20 ton press for about $120. Their stuff always seems to go on sale at one time or another. Everytime I get a flyer, I circle the stuff I "need". I always justify it with the CFO by claiming tools are long term investments.

When you get there - the part that is the trickiest is getting the bearing preload and gear mesh correct. I did not use the special tools described in the service manual. If you take your time and follow a fairly methodical approach, you can get by without. Let me know if you want details. I think you are still quite a few days (weeks?) away from that right now.

Best of luck.

tifosiman

Thanks again Scott. Harbour Freight has received a lot of my money over the last year. There is one on the other side of town, I didn't realize presses were so cheap, I may just buy one there along with some generic gear pullers, feeler guages, etc.

I'm more than a few days/weeks away from doing this. I need to scrounge up the cash for the R&P, then find a source for some new bearings (don't want to pay Porsche price on them, and they really are a WYAIT thing), and then order some new seals and gaskets. This is going to be a long-term winter project.

I may see if Harbour Freight has a stand for the trans. I can at least start spit polishing the case and make it look purty.

Scott at Team Harco

Yep - bearing prices are all over the map. You should be able to match up what you need by taking the old bearings to a good car parts store (not the chains). Chances are good they are already NTN, SKF, *** or Timken bearings and can be cross-referenced off the part number on the race.

You will definitely need a bearing separator to pull the old bearings off. Have lots of sockets, plates and tubes, etc on hand for use around the press. Keep all the old bearing races too. Sometimes they turn out to be the best tool to get that new ones pressed in.

In regard to the price I got on my press - it was a mistake. I went in and asked for the 12 ton press which was on sale for $120. When I unloaded the box when I got home, it turned out to be the 20 ton press! No worries. I found room for the larger press anyway.

Oh - yeah. There are at least one or two internal seals and the two axle shaft seals that should be replaced. I don't think I replaced any gaskets. The side case is sealed with Loctite orange. Remind me to get the number for you. I should still have 1.9 bottles worth of the stuff on the shelf at home. It's nice working in the engineering world - I just called the local Loctite rep and asked for a sample container of "xxx orange". Two bottles arrived a couple of days later. In fact, let me know if you are interested - I can probably send the 0.9 bottle to you.

adrial

A non-LSD trans is more likely to blow up the R&P because one of the tires will spin and then suddenly regain traction...and then... kaboom. Think about being hard on the throttle when you hit a bump...tire loses traction, spins up and then quickly gets traction again...lots of force applied to the R&P when that happens.

86 951 Driver

I want to prevent this from happening on my 924S. What should I do so it doesn't blow up at an inconvient time? I have a new clutch in it. It is about 200 miles old. I have also changed the trans fluid to mobil 1 synthetic.

Scott at Team Harco

OK - I finally took a couple of minutes out and dug through my shelf of Loctite bottles. Here is the sealant you want to use on the side cover.

How'd that crazy Citroen get in the picture?

tifosiman

Thanks Scott!

What gears did you blow up on your trans? Was it just the R&P, or was it more? I took the case to the carwash yesterday (shhhhh) and degreased/cleaned it with the high pressure wash. Next week I'm picking up a press and an engine stand at Harbour freight. Then I'm going to start amassing the small tools and bits.

When you did the baking of the gears, how did you ensure they were the proper temp? Did you use a probe? (he said "probe", hehehuhuhhehu) I think I may look for a smallish toaster/sandwich/efficiency oven at a garage sale or flea market to use for baking this stuff in the garage.

Renee and I were sitting on the back deck last nite relaxing. I had the rear garage door open and it was rather windy. Every once in a while I'd get a strong whiff of gear oil when the wind blew thru the garage (even though the trans parts and bits were under a nice sealed plastic cocoon). I know Renee did too, because all of a sudden at one point she says "If you are thinking about using our oven to bake the gears for that project, you better think again."

Matt H

Damn you are up early, I though I was the only one.
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tifosiman

I get up around 4:30-4:45am every day, including weekends. I can't stand sleeping the day away. On the weekends I use the first hour or two of the day to wake up, drink some coffee, and peruse the 'list.

tifosiman

Scott,

I looked on HF's site and there were no presses on there . Do you happen to have any info on the one you bought, like a part number or manufacturer's name? A quick internet search reveals that presses are expensive everywhere else and would make the project cost-prohibitive unless I can run acrossed one at a place like Harbour Freight...........

Thanks!

Jeremy