4.10 or 3.73 ?

[kerrmudgeon]

Hi , I have a little bus GMC 6.2 19 passenger. It weighs about 7900#. I would like to lower the RPMs a little and was wondering if changing the rear end from a 4.10 to a 3.73 would help or not. The other thing I would like is a 4 speed transmission. Will this help?

The 6.2 is NA. Any and all help will be gratefully appreciated.

Regards to all,
Barrie.

[Robyn]

You could do a gear change or possibly go to a tranny with OD

The 3.73 will help the rpms some but an OD tranny might be a better way to go.

Hope this helps

Robyn

[6.5 Detroit Diesel]

Dang your in Texas other wise it would no problem to find a four speed for you. I have a parts truck and am messing with the idea of swapping from the 4.10s currently in to the 3.73's in the parts truck. But I sat down and worked it out and going from 4.10 to 3.73 is only a RPM drop of 8%, not really much at all. A NV3500 Tranny would probably be to light for the bus, so either a
SM465 with o/d or a NV4500 would work. Or else you could try to find a 4l80 which had a stand alone computer in 1991 which would give you a automatic four speed with o/d that is super strong