Brake booster and proportioning valve

I have a 2000 XJ that I swapped an axle in from an 89? Could there be any problems with my booster and proportioning valve working with the older axle and brakes?

I realize the brakes are worse on the 89, but just curious if anything would go wrong with any of the "other" parts.

Thanks,

Eric

nope....unless there's an ABS issue