S54 Transmission dead?, need help identifying problem Options

[easternpiro1]

Hi all, I wanted to get as much feedback as possible before I replace or rebuild my Transmission.

As it is well known, 3rd gear is notorious for grinding in the GT transmission. mine grinded for sometime but only if I accelerated hard.

One day I was driving normally and chose to pass a slower vehicle in front of me. what happened next completely confuses me.

when shifting down from 4th to 3rd I got NO response, it was as if the car was in neutral. I tried each and every other gear to find that no gear worked (motor revved but no response)

Upon further inspection I noticed that the speedometer still worked while the car was in gear (when car was jacked up and on ground) I also noticed a SLIGHT grinding noise while the car was in gear as if a moving part was spinning and barely touching metal.

I figured my axles were bad, so I jacked the car up again, and slowed down the drivers side wheel to see if my RPM changed any (it did not)

I noticed that only one wheel would spin, and the passenger side would not. When I tried again (using an old deflated basketball to slow the tire) the basketball got sucked under the wheel, and got stuck causing the passenger side axle boot to tear off, and my axle to pop out of the hub. (this tells me that the axle was attempting to spin)

I was told by a friend that my differential is blown. do any of you know this to be true? any help would be appreciated. Thanks!

This post has been edited by easternpiro1: Feb 12, 2015 - 1:50 PM

[Smaay]

LSD wont make syncros go bad. has nothing to do with it. speedometer still works because differential is still spinning. you dont have an axle problem. if one popped out you would lose all your gear oil.

sounds like linkage inside the trans came off or loose. or there might be big damage. you need to open it up to find out.


or just replace it. they are only about 300 on car-part.com

[enderswift]

LSD wont make syncros go bad. has nothing to do with it. speedometer still works because differential is still spinning. you dont have an axle problem. if one popped out you would lose all your gear oil.

sounds like linkage inside the trans came off or loose. or there might be big damage. you need to open it up to find out.


or just replace it. they are only about 300 on car-part.com

First thing that came to mind was a busted linkage/cables as well, but if the shifter feels normal then it's unlikely that the linkage broke or a cable snapped. Doesn't hurt to check though. Anyway, destroying a stock differential is hard man, those things are beasts.

Here's what can go wrong with a stock open diff:

- gears loose teeth and no longer engage. ( If this happens those shards are going to destroy everything in your trans and you would definitely know about it)

- Differential case cracks and the whole thing flies apart. (Again you would be well aware if something like this happened)

- Ring gear comes off or bolt falls out. ( Same thing, it would be a catastrophic failure)

- Bearings go bad and differential is loose inside the case ( This would cause so much vibration that you would immediately stop driving the car)

All the stuff I just mentioned would either grenade the casing, lock up your tires, or cause a LOT of noise. Since nothing like that happened to you I think its safe to say its not your diff.


You may just have blown a clutch. It cant hold enough torque for you to go get any power in gear, but holds just enough to spin the differential ( thus your speedo works) and to spit a basketball.

This post has been edited by enderswift: Apr 23, 2015 - 10:37 PM