Just bought this truck and the transmission is only going into 1st and 2nd gear. CEL is on and 733 and 734 codes are in the TCM. I plan on changing the fluid. As I understand, the filter is inside the tranny and since I am not able to remove the tranny, the filter will not get changed. Is there anything else to check/replace? Thanks!

 

You would require a capable scan tool to do some further checking of things like speed sensors, solenoids in trans not working ..

What you can do is check all wiring connections to the trans . Many times a poor connection involving signals from the trans to controls can produce all kinds 0f problems.

Checking them means unplugging them and look for any corrosion or loose pins.

 

That is something I will try tonight when I get home.

 

Pulled and inspected the plugs and all are good. There is not a bottom pan but found a drain plug. Is the pan facing the front of the vehicle?