[N55 dood]

So basically my 3rd gear synchro is making a weird noise and my job is offering me a m2 mt6, I was wondering if anyone knows if it will fit into my 2015 m235? Also would the diff ratio matter if I do end up swapping the tranny for the m2 mt6?

[aerobod]

Originally Posted by N55 dood

So basically my 3rd gear synchro is making a weird noise and my job is offering me a m2 mt6, I was wondering if anyone knows if it will fit into my 2015 m235? Also would the diff ratio matter if I do end up swapping the tranny for the m2 mt6?

Both cars use the GS6-45BZ transmission, the SHCK variant for the M235i and SHBS variant for the M2. There is a good chance the bellhousing, output flange and shaft splines are the same (Sachs shows the same clutch fitting the F22 and F87). Gear ratios also seem to be nominally the same, too. The variant differences may not be significant, but it is worth measuring the output shaft and bellhousing bolt positions on your car and comparing to the M2 transmission to confirm.

[N55 dood]

Originally Posted by aerobod

Both cars use the GS6-45BZ transmission, the SHCK variant for the M235i and SHBS variant for the M2. There is a good chance the bellhousing, output flange and shaft splines are the same (Sachs shows the same clutch fitting the F22 and F87). Gear ratios also seem to be nominally the same, too. The variant differences may not be significant, but it is worth measuring the output shaft and bellhousing bolt positions on your car and comparing to the M2 transmission to confirm.

The gear ratios are similar but the final drive for the m235 is 3.06 and the m2 is 3.46

[aerobod]

Originally Posted by N55 dood

The gear ratios are similar but the final drive for the m235 is 3.06 and the m2 is 3.46

If you are not swapping the diff, too, it will drive the same with just the gearbox swap. If you are swapping the diff as well, then the driveshafts, subframe, stubaxles, brakes, rear suspension, wiring and programming to add the electronically controlled diff are all different on the M2 and likely will need modification, too.

[XutvJet]

The GS6-45BZ gear ratios are the same between the M235 and M2/3/4 6mts. The difference as I understand it is that the SHBS part number has stronger syncros.