A friend of mine has a school bus with a blown 6.1. it has a manual five speed in it and hes looking for a replacement motor.

What transmission would it have? Zf5? Also what motors would bolt in place?

I never heard of the 6.1 untill looking on here. I see its part of the 429/460 family. Would a 460 bolt in?

 

The trans may be a ZF, might be a Clark. There should be a data plate somewhere on the vehicle with the axle and trans codes.

The 370 is related to the 429/460, but will not interchange with the car/light truck engines. Another 370 or a 429 from a medium would be the way to go. (crankshaft and bell issues iirc, there was a recent thread I'll try to find)

 

This has some info about the differences.

https://www.ford-trucks.com/forums/1...n-a-460-a.html