Allison 5sp: 03 trans in an 02

[JustinD]

What needs to be changed to run an 03 Allison in an 01-02 truck?

 

[blk smoke lb7]

I think the trans fittings are 3?4 on the 02 and 7/8s on the 03. They did make some 03s early with the old trans and later they were the same as the 04 trans I think there is a cut off date. Check the tag on the trans for a manufactures date.Otherwise I'm sure Mike L will know.

 

[Mike L.]

Maybe nothing needs to be changed. Early '03 had the same fittings as '01/'02. Later '03 had the same fittings as '04/'12. If your '03 is a late one you need only goo to chevy and buy the adapter fittings. All Allison factory remans only come with late bell housing and adapter fittings.

 

[JustinD]

Fittings were the only difference so we swapped bellhousings and slammed it in. Thanks guys!!!

 

[cwmeaux1]

Is the p/n switch capitable also 02-03

 

[JustinD]

Yes same NSBU switch