I have a problem with my 48re! I had to take it to dealer for the TSB 1-2 shuttle shift. They replaced the governor pressure solenoid but not the sensor. It was also hard shifting when put into drive from neutral and also into reverse. Shift hard in all upshifts harder sometimes than others. The shuttle shift was fixed though with solenoid change.

I decided to get another solenoid, sensor and a transgo shift kits from transmissionpartsusa.com.

Before install i ran voltage tests and psi tests according to the ATSG transmission manual. voltages were off the wall and everywhere. On the psi test at the governor port I was getting 0 psi at idle like book says it should but I would test again after restarting truck and it would go straight to 60 psi at 0 mph at idle.

I put the new solenoid, sensor and shift kit in by the book and still have hard shifting and wacky psi and voltage readings. Here is what I came up with.

MPH-sensor volts- gov ground volts- gov psi
0 ----- .44 ----- 9.06 -----0
10 ----- .66 ----- 9.55 ----- 5
20 ----- .93 ----- 9.85 ----- 12
30 ----- 1.13 ----- 10.14 ----- 20
35 ----- 2.30 ----- 11.42 ----- 60
40 ----- 4.68 ----- 13.94 ----- 60+
50 ----- 4.68 ----- 13.92 ----- 60+
60 ----- 4.68 ----- 13.94 ----- 60+

Line pressure at accumulator test port idle 65 psi, 100 psi max.
Jumps to 120 psi in 3rd lockup, 4th, and 4th lockup.



I took to dealer and took three hours to come up with that the line pressure was 8-12 psi over spec and that the pressure valve was sticking and would cost $800 to fix. Doesn't a shift kit boost the line pressure up atleast that much???

SOMEONE PLEASE HELP!!!! Is there a computer problem like I am suspecting???

THANKS

 

might want to try and post this over in the Diesel section. you will get a lot more help than you will in here.