Is there any difference between a gas and a diesel nv4500? What is the first gear ratio in a diesel?

 

Yes they are different.
Heres some info.

http://www.quad4x4.com/NV4500FAQ.htm

 

the gasser has a 1 1/8 input shaft compared to the 1 1/4 input on the diesel, gas wont work with any clutch made for the NV4500 in a diesel.

 

new input shaft is about 65.00 and can be changed in 15 minuets

 

depending on the model the main shaft is different to. Most gasser's (except v10) had a NV4500, diesel and V10 had the NV4500HD, which in the 4wd models has a 29 spline main shaft, in 2wd models I believe its a 23 spline