Opinion-explaination welcome.

Went from OEM LT245 to LT265.

Past up shift RPM points seem to have been raised, and also seems that when going into next upper gear, especially OD shift points hang longer.

All maintenace-fluids(SynTran) & filter (external) done.

No codes shown.

Thanks

Actually, the 3500 single rear wheel axle truck uses the 265 tire so there should be no problem. If you had went for a 285 or taller there may have been issues.