BRP Shims for rc18t

Without knowing the kit nor the RC, my answer will be yes. The input shaft bearings need to be looked at and shimmed if needed as well as the outputs.

Shimming is a learned art. You dont want to get anything to tight and cause binding nor do you want anything to loose to cause excessive wear. If you have to make a choice, looser is better then tighter.

After you place the shim /s put the part back together including the screws and check the fit. Sometimes when you bolt everything back together the parts flex a bit. Its not unusual for me to check and adjust a diff 3-4-5 times before I'm happy with it.

Welcome to the next level!
IMO, Its worth the extra time and effort.

Well, I got the diffs together, and it looks like the stock AE rc18t shims that is came with are fine. diff feels pretty tight. Only time and running will tell... thanks for the response!

well, on mine I used one BRP shim on each outdrive. I tried the ones on the input shaft but didnt need it. Put one on each output and it should be fine, it made them hold up to my mamba 6800 and 8 cell pack.