GT1

I think I got a bering in my transmission going very bad in a hurry ... ive been noticing some harshness over the past couple months, but in the last 2 days its started making a grinding noise accompanied by a fast knocking at lower rpm, deceleration and at idle .... but when I press the cluth, it stops completely??? Just wondering if any of you know if my beeing guess is right, if its fixable, or if i should get a new trans .... possibly a second gen one if it goes in easily?

thanks in advance for any input.

peejay

If it makes the noise while the car is sitting still then you can eliminate the driveshaft and rearend.

From here it sounds more like it could be a throwout bearing problem. But it is possible that one or more of the input shaft's bearings have failed. If the problem greatly lessens or even goes away in 4th gear then it's definitely a problem in the transmission. (If you have great difficulty even getting into 4th gear compared to the other gears then the transmission is definitely the culprit)

Also check to make sure the engine has no eccentric shaft endplay. (See if you can move the front pulley in and out more than the width of about one or two business cards)

Regards to rebuild or replace... if the trans does turn out to be the problem, it's much cheaper if possible to find a junkyard transmission and put it in. Just disassembling the transmission to get at the bearings is a pain in the *** with the correct tools (various gear pullers and adapters for a big ole hydraulic press, and an air hammer helps too) and it would be a complete nightmare without the proper tools. basically, this is one job for the pros, and the labor would exceed the cost of a junkyard transmission.

You *could* put in an FC trans, but it requires a bit of work (swap tailhousings on 81-85, considerably trickier for 79-80), and this is a possibility if you can't find an FB transmission locally. There is no strength advantage, and 5th gear is so much taller that you may find it useless, unless you drive downhill a lot.

Redwood

Get a junkyard one if it's the tranny. Much easier than rebuilding. I think everyone will tell you that.

Have you checked the transmission mount? It is possible that it is just loose or the rubber supports are completely shot. I drove a 79 with the tranny mount installed but no rubber stopper in there and it shook and knocked like a bitch. Worth checking before dropping 75 bones on a tranny (please don't pay more than $100 for a tranny as they are pretty much everywhere, BTW).

peejay

Ah but a mount won't cause grinding...

Also I would love to find out where you can get trannies for $75, I will go there and buy them up and sell them here for $150-200.

gump

I have noises, maybe similar to yours, from my transmission that greatly lessen and sometimes go away in 4th gear, i think i got a bum tranny. Long story short: I took the GSL transmission I had in my GSL-SE out after 18 months because when I put it in, the spring that keeps the shifter in the center after pushing it to the left and right, was broken. I picked up a GSL-SE tranny on ebay in the mean time that was supposedly good and only had 50000 miles on it. Yesterday comes, I decide to take out the old and try the GSL-SE tranny. I take the good working but broken spring transmission out and put my $50 ebay GSL-SE tranny in along with 2 quarts of $9 mobil 1 tranny fluid. it sounds horrible in the car in all gears but 4th. 6+ hours of work and now I have to do it all over again! Moral of the story, be careful when you are looking for a tranny. I paid $250 for the good GSL tranny I got from a junkyard and it worked fine (except for the broken spring). I paid $50 for a GSL-SE tranny from ebay and its trash and I get to do it all over again now. Sorry, I just had to vent and this was the perfect thread for it.

Anyone have any questions about changing a tranny in their GSL-SE, drop me a line, i'm becoming a pro.

Stripgear

iTrader: (2)

This is why I prefer to rebuild vs. go to the "junk"yard.
Yes you will need access to a bearing puller, a press and you will need to make one special socket. But if you have some mechanical ability, its not all that hard and when you are done, you should have some thing that should last for over 100,000 miles. Just my 2 cents.
Also, I work at a bearing house, so if anybody needs bearings I can get most of them for you at a discount.
Most bearing houses mark up bearings to the general public about 40%.

Jeff20B

iTrader: (13)

My tranny is a '74 four speed and has a slightly bent input shaft. This caused a ruh-ruh-ruh-ruh sound at idle which increased with engine RPM. I only found out the shaft was bent after I installed it in my MG Midget project and had somebody spin the rear tire so I could watch the shaft spin. It has planetary or eccentric movement as it spins. I think it's out of spec (I could barely see the movement as it was only like 1mm or so at the tip). This can't be good for the pilot bearing. However, it used to be in my '74 REPU and the pilot bearing was fine. I changed it as a precaution only to find out it was ok. Oh well, preventative maintainance is always a good thing. By the way, the noise was from the tranny being empty. It was never that loud in the REPU (I had to drain it to install in my project and ran the engine briefly to check for leaks but never drove on it). I just recently gave it some oil and reinstalled the engine. We'll see if it makes that sound anymore.

Manntis

I recently had the tranny rebuilt in my car, and it wasn't that expensive. One of the bearings is $70 (CDN) but all told it only came to a coupla hundred bucks, and I've got a like-new tranny whose numbers match the drivetrain to show for it.

Redwood

My fault, I guess I didn't catch the grinding part.

I've picked up 2 trannys thus far. One from a local RX-7 guy, who was parting a GSL; $75. The other was from a friend who wanted to ditch his parts car. I took the car, pulled the tranny, and paid $50 to have it towed away (it was pretty stripped and beaten).