New user, auto problem 95 4.2 TD

[hexham-scotty]

Hi Everyone, I hope you can help.
Recently when towing a trailer the AT overheat light came on and the O/D light started flashing.

Very occasionaly it drives perfectly normally, usually when cold, changes all gears etc.

Most of the time it skips 2nd gear (jumps 1st to 3rd) have to shift 2nd manually. O/D dosen't appear to work (or it is in O/D, not sure which) it is very sluggish due to being in the wrong gear and eventually the O/D light starts flashing).

Things I have tried so far;

Flushed the oil several times, cleaned the filter.
Removed and tested the 4 gearbox solenoids (blow through and electrically )
Checked the wire connectors above the starter (all fine)
Replaced the TPS on the fuel pump with a new one.
Gear oil is on level and clean.

I cannot read the fault codes as every where I have looked on the net says jump the centre terminal with the top right one ( in my test port the middle pin is not there ? )

The temp gauge works fine as does the speedo, I am sure the box is fine mechanically, I guess an ecu or wiring fault.

I am a competent mechanic with electrical knowledge but am completely stumped now.
Need my beloved truck for towing, please can anyone help ?

Cheers Scotty

 

[Brett]

I think you need to move this to the 80 Series forum Scotty.

 

[swampy]

I was having the same sort of problem.As it turns out there is an oil pressure adjustment in the automatic box mine was to high and wouldnt always back shift unless I was towing also the TPS was only getting 1/4 throttel.
I took it to a Good Transmision speacalist and got a service and adjustments for $200.
I hope this helps

 

[Jon Wildsmith]

I would have another go at trying to read the fault code. I know you said the pin isn't there on yours but what was your source of information for which pins to short and are you sure you got the right ones?

Did this all start with the over heating, or just before and then caused the overheating?