Getting into this swap myself. I have an 06 RCSB 2wd with rear drum brakes. My master is wider then the hydroboost studs. Was looking to pick up a master from a 2500. I'm under the assumption anything with hydroboost will have rear disc's. I've been searching with people saying hydroboost will work with rear drum brakes. I'm looking to see if anyone knows the difference in master cylinders? Will I have problems using a different master? Or is the difference in the ABS with proportioning? Thanks.

 

Did the swap on my 06 crew cab with drums and everything works fine. Used ACDELCO 178-0700 booster and ACLELCO 18M1107 master cylinder.

 

I have a hydroboost out of a 07 to try in my 06. I may try the 07 master as its a bit cheaper.

 

Checking in after 7+ years of use... Same HB unit, MC, and pedal. Working great without issues, I've towed and hauled all kinds of stuff doing truck things over the years. Just letting folks know it works great and I would highly recommend it.