What gears do I have?

[65chevysub]

Originally Posted by MJN

GQ1 simply means its the standard gear ratio available for that particular model, in this case C20903 or K20903. But since you have C6P- you have either a C20 or K20, so GQ1 is either 3.73 or 4.10. This then depended on the transmission- MX0 is 3 speed auto and MX1 is 4 speed auto.
Since yours is TH400= MX0 so then you got 3.73
https://www.gmheritagecenter.com/doc...olet-Truck.pdf

*I see from some of your other posts you have a C2500.

It's a C2500, and the Trans code says MX1, 3-Speed Automatic Trans. Codes must have changed from year to year? I'm going to get the original build sheet etc from the GM Heritage center for it, and will see how correct the SPID is.