Green Egg Sam

I'm trying to sort out a shudder that seems to come from right rear, similar to many other posts I've read, upshifting to 4th or 5th at relatively low speed causes it. Kinda sounds the same as running over lane edge warning strips. Same downshifting if rev's aren't matched perfectly, especially 5th to 4th. Using reverse going up a hill accentuates the shudder. I have determined that the right rear wheel bearing has some play in it, and will be rebuilding it soon. The mounts to the transaxle appear to be in good shape. No noise/clicking on turns left or right. I could not feel any looseness in the cv joints on the lift. My plan is to repack/rebuild the cv joints when I service the wheel bearings. When under the car looking for any problems, I noticed a clunking noise coming from the back of the transaxle when I rotate the wheels when the car is on jack stands. Seems to be some play inside of the gearbox, is that normal? Transaxle is noisy at highway speeds and I did add Royal Purple 75-90 gear oil to it. Any thing I might be overlooking? I can avoid the symptoms by driving it right but using reverse up a slight grade can be a pain.
Thanks, Sam

John_AZ

Did you "add Royal Purple 75-90" to the existing gear oil or completely replace the old oil and add new?

If you replaced the trans fluid, did you see any silver metal flakes?

Do the repairs you listed and good luck.

There is an inspection plate on the side of the transaxle. You might want to remove it and inspect the ring and pinion. Bad news if it looks like this:



GL
J_AZ

Green Egg Sam

Thank you, when I drained the old gear oil, it looked brown and somewhat milky. I looked carefully at that time and did not see any metal fragments, then filled it with the Royal Purple. According to car service records it was changed last about 4 years ago, but only about 15k miles. When I rock the wheel forward and back, that is when I can hear a clunk in the transaxle, like there is some play in the gear as it goes one way, then the other (in neutral). If I have any transaxle trouble to repair, is there a beefier unit I can put in there, I'd rather swap out transaxles than have down time, I do use the car to drive 60 miles to work every day. If not I could look for a good series 1 transaxle, I guess. Driving down the highway there is a bit of a whine I hear from the transaxle, but it isn't severe.

John_AZ

When you work on the transaxles and CV joints, mark each axle --L & R --and the CV joint on each side--Inside-Outside.

Swap the transaxles to the opposite side of the car--keep outside to outside. This will put a new surface for the ball bearings to ride on.

Replace CV boots if damaged.

J_AZ

konakat

It lasted 30 years, you can't ask for much more than that. N/A transaxles are cheap, about $300 for a good used one, so it doesn't make sense to do much more than swap it if necessary. Turbos have hardened gears, but the ratios are taller and won't work so well for an N/A.

Dimi 944

I completely agree. Another better option will be an NA tranny from '89 944 or 944S. They have stronger internals and the gear ratios are not much different than the earlier versions.

I would be cautious about the "$300 for a good used" tranny. Many transmissions come from the same era pre-'85 cars and could be in worse condition than the one being replaced. My advise is having a used transmission inspected and rebuilt if one is looking for another 20 years out of it.

Holytin

Agreed 100%. My original transmission failed on my 1988 924S about 10 years ago and I purchased a used tranny for $1,200 from a 944S "inspected" with 100K miles and a 3 month warranty. This transmission didn't last 6 month although I did pay a premium.


Imagine a $300 transmission...


Should my original transmission fail today I would consider a rebuild to keep the car #matching (my transmission has a VIN # sticker). I just don't believe there are any really good ones left. But that's just me...

pdxfj

I bought a used transmission off Craigslist and it was crap. I ended up sending one of them to Kevin Gross @ Catellus Engineering to be rebuilt. Not cheap by any means, but I shouldn't have to do anything to it for quite a long time.

How's your clutch? Any idea if it's ever been changed? When the original rubber centered ones go south, they do all kinds of strange things.

This explains a lot.

Green Egg Sam

Thank you for the helpful replies, I agree that swapping out with a questionable transaxle might be iffy. I'll take a look at the ring and pinion, double check the clutch (I'm pretty sure it is ok) and go ahead with the service of the cv joints and that wheel bearing. If that doesn't do the job, will search for a good used unit. I live in north central Washington, any good service shops with proper experience and tools that could do a transmission rebuild?
Thanks, Sam

pdxfj

I checked around and there are not many people who can properly rebuild a 944 TA. There are a few specialty tools needed and parts are not cheap. I found one place in Lake Havasu that does P-Car T/A's but couldn't find many reviews. I did find quite a few reviews here and Pelican about Kevin.

With mine, once Kevin got it apart he discovered the races for the two main bearing races were rather easy to remove. They are not pressed in, you heat the case to about 350 degrees and drop the races in. Then when the case cools the aluminum shrinks back down and holds the race in. He said it would likely be ok for a driver but any kind of track time could spin a race. So I chose to spend a little extra and have him replace the case with a good used one.

It was amazing how much tighter, quieter and smoother the rebuild TA is. Kevin is located in Massachusetts, but shipping is not too bad. He's done about 150 T/A's over (roughly) 20 years.

When you're under the car pull the rubber inspection cover off the TA and see if you can move the drive line at all. If you still have the rubber clutch and it's gone bad, you'll be able to move the drive line.

Of course this is just my experience and could be worth absolutely nothing. )