naharra

At work we have an 06 3500 with a 48RE and first gear doesn't shift to second until 2300 RPM even at very light throttle. All the other gears work great upshifting and downshifting.
We just rebuilt the trans with a new governor solenoid and transducer and installed the Transgo 48RE kit.
It had these symptoms before as well, but cooked the front band out of it.
I'm thinking of checking the wiring harness for breaks, any other ideas?

cdennyb

check the TV cable tension or adjustment. Too tight will make it rev higher i think. Look into that part first and see if you can determine if that will make the difference you speak of.

soulezoo

Try readjusting the front band. When I had a similar issue, that fixed it.