Hello,

I currently own a Volvo 245 L first registered in February 1976 in France.
The engine is a B20A mated to a M45 gearbox. I know this configuration is pretty rare, but I checked it and it’s really a M45.
Now, I would like to know if it’s possible to keep the bell housing and install a M46 instead.
For sure, the length of the shaft that links the gearbox to the rear diff is different however would it be any other element that can make this swap not possible ?
Someone has done this swap eventually? Thanks for help

Christian

 

Sure I've put a 4sp with electric overdrive (m46) in a car that came with a 4 speed (m45).

The differential is a different ratio in a 4 speed car so you have to find the speedometer drive gear (in the transmission output shaft area) that works the best (there's 3 choices I think) so you speedometer is closer to accurate. Shorter driveshaft and switch and wiring and relay ( if push button, I don't think the slide switch has a relay) for the overdrive. Those overdrive units do wear out - I've rebuilt maybe 20 of them - so make sure it works before installing it. Being that old your best bet might be a m47, the pure 5 speed.

As far as I know the bell housing is the same m45/m46. The m47 might be different (but it's been 35 years since I converted a 78 242 from 4 to 5 speed)