[Trai Krebs]

Hello all,

I have been doing tons of research but I can’t find any differences between the 53DZ and 53BZ transmissions.

The 53BZ came behind the N54 135i and from what I’ve heard it’s rated up to ~450-500ftlb torque.

The 53DZ came behind the N54 335i but I hear of it surviving behind 1000+hp builds (I’m assuming way over 500 torque).

I have a N55 135i and I know the logistics behind swapping the 53BZ from the 1 series into my car but my end result build will probably be a hair over the max torque for the 53BZ so I’d rather swap the DZ if the high hp fairy tails are true.


Does anyone know if there is any difference between the BZ and the DZ in regards to strength as well as assembly (bell housing bolt holes lining up, input shaft/pilot bearing differences etc.)