I got to drive my car around for the first time today. I have a really loud whine from the transmission when in 3rd gear and under power. As soon as I let off power it stops whinning. It only does it in 3rd gear. What do you guys thing this would be? bearing? syncro? I'm definately not a transmission guy. I guess this would be a good time to switch to side shifter?

John

Bearing. Not a syncro.

been running it alittle low on oil have we?
Top intermediate bearing is going.....


Geoff

Thanks guys. I have never run this trans low on oil. Its full of mobil 1 right now. It did sit up for about 6 years and the gear oil had turned into grease.

I guess my next question is how hard is it to get to this bearing? Do you guys think its worth repairing this tailshifter trans? I have redone the shift linkage completely. So although a bit rough at times I can get all the gears.

John

It does not really matter, as the side-shifter you get as a replacement could have the same issue. If you repair this trans you could still convert it to a side-shifter later without losing your new parts (the gears/bearings/syncros/shafts are the same between the two).

You'll have to pull the engine/tranny and disassemble the tranny to replace the bearing.

and while you're at it, replace the mobile 1 with swepco

you can exchange the guts from a tail to a side.
no need to throw away the good parts ...
Andy

Nah, you can pull the gear stack with the intermediate plate out with the tranny still in the car. The problem is getting it back in without toasting the pilotshaft seal.


Geoff

I have seen 3 pinion bearing races loose in the 901 case cause the same symptoms. Right now we dont have a fix for it... you can buy new cases from Porsche however. I dont like the trend I'm seeing.. it is not good for us. The 915's already have a fix available. Hopefully we come up with something soon.


B

a little OT, but here goes.... i am comfortable working on anything on my car BUT the transaxle. it scares the bejeezus out of me. i need to be cured

take one apart its fun. Gear parts all over the place, springs pop out and try to put your eye out, etc. Great fun thou.
The only problem is the parts are sooo expensive!!!! yikes.

Geoff

LOL my fears personified!!!

Geoff,
Thanks for the boost in confidence. The internals of a car transaxle are the only thing I have never work on in a car.

Thanks for the info guys. It shouldn't be any problem to let it ride for a week or two as long as I avoid 3rd right? I'm in the middle of moving and really cant tear into my tranmission at the moment.

John

Just make sure its full of oil.

Acox914



If you dont want to screw up yours, but want to overcome the fear, buy a boneyard trans or one off e-gay for $50-$100. Take it apart, re-assemble, take apart, etc. They aren't that difficult. If you have done an engine, you shouldn't have a problem with a trans. The main thing is to keep everything clean and keep track of the thickness of the gaskets (shims) as you remove them.

Follow the steps in the workshop manual.

Keep everything very clean and use quality lubricant.

-----------------
Brad,



Is that the race up in the main case? Isn't that a smooth bore and a roller bearing?

Go to a quality Bearing house and talk to them about a slightly larger OD race. They should be able to match up the bearing with a larger OD race. (You should also have them price the roller bearing) The bearing supply house should be able to redily supply all the trans bearings except for the special flanged intermediate plate bearings. I had a cross-reference someplace on the 901 boxes...

You could also take the case to a quality machine shop and have them either rebore that and cut a new snap-ring groove or something.

Is this "trend" with higher output motors, or is it even with the stock 4-cyl cars?

Advice I'd offer on first-time trans rebuilding is to not only keep things clean, but keep things organized and labelled. Unlike an engine, there are a lot of similar looking parts in a gearbox that aren't interchangeable. Again, this isn't difficult. Using a sheet of heavy paper or cardboard as your working surface, just lay the parts out in order of disassembly, writing their identity on the paper/cardboard as you go. If there's a chance (as there nearly always is in DIY rebuilding) that there will be a significant span of time between disassembly and reassembly, use tags and label the bits that way.

I used a permanent felt marker to label the gears, shims and such so I could tell easily what they were. If you jumble up everything it takes time to sort them out. I did this to a spare tranny that I then stole some parts off. Took alot of time to figure out what gears were what ie counting teeth...etc.

Geoff