5.9 120k.
Bought from a production company a bit neglected.
Drove on temp tag July and found some issues.
did major engine service…Plenum, 4 hole injectors, timing chain, Oil pump, rear main, water Pump, motor mounts……

Trans- adjusted band and changed filter . Used universal synthetic fluid.

* started driving van regularly November at 119k
after 500 miles started getting P0740TCC torque converter code. Trans worked fine.

* longer hiway trip yesterday and after 20 miles OD dropped out and OD switch light illuminated.
* checked fluids etc….restarted vehicle and OD worked fine….. 20 miles, dropped OD again

and so on….,
drove for a bit in 3rd to get home maybe 60 mph.
pulled off hi-way in “Drive” and van didn’t move.

Pulled first and trans sounded like a bucket of rocks dropped but got it moving and home.
Parked Van 1/2 hour and took a quick ride to grocery and all worked ok under light load.

What gives?
Solenoid, Clutch Packs, Sprag, converter?

im not a trans rebuilder but understand general function…..727…:

Thanks in

advance for help!

 

Your universal fluid may be part of the problem. These guys like ATF +4, and nothing else..... The rude noises you were getting though, that is just not a good sign...... May wanna drop the pan, and see what you find in it.

 

There is a 2-wire that goes to the front of the tranny to control the TCC. Sometimes this wire rubs the bell housing and the insulation wears off causing the conductors to short to ground.

 

HeyYou is right. atf+4 only. its worth swapping coolant line that has check ball ( TC Drain back check ball) replace it with open line for more flow. there s a thread on here with how to do it your self. (also reccomend upgrading shift kit on valve body) these lines clog and reduce fluid flow- it fried my OD planetary and the bearings it rotated on- metal shavings everywhere in pan. as far as dropping rocks sound you may just want to rebuild entire trans if you're shredding metal. could be a broken snap rings or OD accumulator spring inside.. trust me i just rebuilt mine and totally worth the time and experience. also if your governer pressure solenoid is clogged -replace it.