Lowes has a pretty decent 3 ton floor jack with 2 jack stands for 99.00, I just bought one. It works pretty good has the one pump quick raise feature, the jack stands are a bit cheap, but work well for light stuff. Oh its a Kobalt brand.
Brayden Fleece At Fleece performance engeneering, Danville, Indiana, just west of Indy,
He is very knowledgeable with the ali and other things, you can get his info off the old site vendor list. Oh and he builds Sun Coast trans I believe.
That has a lot to do with what drive train you are using, different axles ratios, wheel size transmitions all play in to what the drive train loss is. So to say that every truck has 20% drive train loss is a broad gemeralization, that si not so acurate.