I don't know if it is normal or what but here is what it does. If I kind of get on it hard, not floored but into it, it shifts into 3rd and right into 4th. What do you all think? Is it because of my 315's?

Confused! Usta

 

Have you recalulated your speedo yet from the dealer? I am bringing mine in on Thursday to have them adjust the computer to make up for the tire size difference. Going to use 601 as a number.
My tranny does shift different since going to 315's a couple of weeks ago. Seems too be a little sloppy.

 

Yes the dealer installed the tires and I had them recalculate.

Usta

 

I'll bet its second your missing , I'll bet your truck is going into second so soon you think its in low and your mistaking the 2-3 shift for a 1-2 shift and so forth up and mistaking the 4th gear torque converter lockup for the 3-4 shift.
If you take off easy my truck will make a 1-2 shift within 8-10 feet from start and smooth as silk with no rpm change. If your not really looking for it ,or feeling for it, you never know it shifted.