48RE won't shift untill 3000 rpms
 

My truck started not shifting to 2nd or 3rd untill the RPM's reach around 3000 rpm's??? fluids are good! anyone have any idea's

Scan and check gov pressure. Check line pressure. If its high you might have a malfuntion of the tv motor. The gears are plastic and i have seen a few issues like that.

interesting thanks

I have seen the 2 sensors on the valve body cause that problem also. R&R and it should fix the shifting problem.

I had the same issue and it turned out being the VB i guess the aluminum will wear out and let pressure go by the spool valve. It isnt noticed on a stock VB but when the pressure is turned up it will. Does it shift normal into O/D or Lockup?

First check your tv cable to see if it is hanging up(assuming it is the 03 in your sig). Have someone floor it while you are underneath and see if the tv cable returns all the way. next step if would be to put it on a scanner to check out the gov solenoid. Your govenor solenoid pressure should gradually increase with speed to about 130 psi when it shifts to fourth. If it is not a smooth increase, hangs at a low pressure, or jumps around alot, you have a bad solenoid. I am on my 3rd one, they are crap no matter where you buy them.