Please Help !!! Important Question For Tranny Experts

[e34it]

Is it possible to have a NON-Getrag 280 trannny operate properly on an e34 m5 3.6. I think my mechanic may have replaced mine with a different model number. He says the numbers on the cases match perfectly as the one that came off of my car but was having a problem with the linkage being too short, the trannys look exactly the same, but the only difference so far is the linkage problem, which he says he can make it work fine. I need advice and fast please!!!!!!

[Tiger]

If model number match... then the only thing that can be different is the flange... which should be swapped from the original one to the new one. Go look at the tranny yourself... make sure it is exact same one.

[e34it]

so if the number etched into the tranny case starts with the number 260.###.####.## does this mean that its a getrag 260? or is this indicated elsewhere on the tranny? so if this is true than a getrag 280 would be 280.###.###.##, right? im so confused

[Tiger]

http://www.getrag.com/176/176

What kind of gearbox does the E34 M5 have?
All M5s built before May, 1994 have a Getrag 280/5 five-speed manual gearbox with the following ratios: 3.51 (1), 2.08 (2), 1.35 (3), 1.00 (4), 0.81 (5). These cars have a 3.91:1 final drive, with the exception of North American-spec E34 M5s built to 1992 and 1993 specification which have a taller 3.73:1 final drive for better fuel economy.

As of May, 1994 production, the five-speed was replaced with a Getrag Type D six-speed manual box with the following ratios: 4.23 (1), 2.52 (2), 1.66 (3), 1.22 (4), 1.00 (5), 0.83 (6). A taller 3.23:1 final drive was fitted at this time.

All E34 M5s have a standard limited slip differential with a maximum locking of 25 percent.

Metric Mechanic said 280 tranny is standard... yet they offer Getrag 265 conversion.

[e34it]

So ok, but if what i said above is true, then am I fitting a Getrag 260 on my m5 then? If thats the case what are the consequences?

[Tiger]

For the tranny side of the equation, there are three different trannies used in E28s. First we will concentrate on the two overdrive units. These are the Getrag 260 and 265. The 265 has a removable bell housing and is used in only the '85 model year cars. BMW upgraded to the 260 which has a one piece case, but shares the internals. The 260 parts are stronger and use the following ratios.

First - 3.83
Second - 2.20
Third - 1.40
Fourth - 1.00
Fifth - 0.81

Yes, you are fitting a 260 tranny. Gear ratio is different... 260 has higher gear ratio... meaning faster pickup in gear one two and three. It came from 525i or the 535i car that is less HP and Torque... and I don't know the spec... I think you will wear out the tranny faster if not destruct it.

Stick with stock tranny or upgrade.

Ask Metric Mechanic about this problem... I think they chose a 265 tranny so they can alter the bellhousing to fit onto a M5. This is beyond my knowledge.

[e34it]

Thanks for all of the help