Getrag 4-Speed Manual Reliability? - PeachParts Mercedes-Benz Forum

JEBalles · #1 03-10-2010, 04:41 PM

Last winter, the splines on the flange attached the output shaft of my Getrag (aluminum case) transmission were stripped under normal driving conditions, incapacitating the car and damaging the splines on the output shaft (see Four-speed manual Transmission Rebuild for more details). I replaced with the same model transmission with unknown mileage. Since I am going to be farther than 3,000 miles from home at times this summer, I'm a little wary of it's reliability.

Has anyone else had trouble with this transmission?

My only theory for how it could have failed was that maybe the nut backed off a bit and not all the splines were together and it may have allowed too much play. I only say this because it was considerably easier to take of than the one on my MB steel case that I'm rebuilding. If that's the case, I guess I should just take the nut off of the existing one and locktite red it and torque it on there real tight.

t walgamuth · #2 03-10-2010, 07:24 PM

I've never heard of a spline failure on a mb tranney. They are known for extreme reliability.

JB3 · #3 03-10-2010, 07:25 PM

They are pretty robust, the problem you describe sounds to me like a fluke situation, however horrible.

Several examples-

1. I towed an 81 rabbit on a dolly 1400 miles behind a 240 with the getrag 4-speed. I beat on that sucker, and had 3 adult men in the car. No problems apart from having to replace the shift lever seals after the drive.

2. I towed a fully loaded cargo trailer with about 2000 lbs of stuff on it three times halfway across the country with the getrag 4-speed behind a 617 when I moved. Performed flawlessly.

3. I went on a 5500 mile road trip up into canada and down through CA and stuck to back roads, mountains, coastal curves, and plenty of quick shift changes with the same getrag 4-speed behind a 617

If all your bolts are tight, I would trust it just fine with almost any use. I was a convert after the rabbit tow, cause we were passing people with that load, and crossed through the mountains. It was almost an attempt to destroy the transmission, but she just kept going.

Stevo · #4 03-10-2010, 07:31 PM

I have never had any tranny problems.

JEBalles · #5 03-10-2010, 09:15 PM

Well this is a good sign. Should I bother trying to tighten that bolt?

hey_allen · #6 03-10-2010, 09:57 PM

I'd say there is no harm in checking that bolt torque, but it shouldn't have been loose at all.

Maybe the failed one developed some slack due to the damaged splines allowing the yoke to seat a little further?

t walgamuth · #7 03-11-2010, 06:01 AM

I wouldn't monkey around with it unless I had some definate reason to believe it was loose. Its not a maintenance item.

barry123400 · #8 03-12-2010, 01:47 AM

I think that four speed was used behind gas engines with a lot more power. If so it is well understressed on our older low power diesels. The problem you experienced before was perhaps just a fluke.

JEBalles · #9 03-12-2010, 10:51 AM

Quote:

Originally Posted by barry123400

I think that four speed was used behind gas engines with a lot more power. If so it is well understressed on our older low power diesels. The problem you experienced before was perhaps just a fluke.

That's good to know and bodes well for my 617 install. Does anyone know exactly what engines this trans was paired with?