99' F-350 auto trans and 7.3

dieseldoc · May 4, 2013

Havent had much time to look at this truck yet. I am not much of an auto trans guy, have never really worked on any. Have a 99 F-350 drw with 7.3 4x4 with auto trans. Customer concern of no forward/reverse unless lever down in 2 or 1 on indicator. I hooked up and and had P0705,P0732 in history. Pulled a P0705 in KOEO test and P1705 in KOER test. The cust. was running down interstate and took the off ramp, stopped at the light. Tried to accelerate from stop and engine speed increased but truck did not move, dropped into 1 and truck moved. Tried to back into a parking spot and it would not go into reverse. Fluid level is full, inspected connectors at the trans and no corrosion or bent terminals. Thats all I've had a chance to look at right now. Curious if you guys know of a common thing(fuse, sensor adj., etc) I should look at or just send him to the trans shop? Hes been a good customer, but this is a bit out of my expertise(lack of experience and tooling, etc). Thanks for your thoughts guys

Bruce Amacker · May 4, 2013

There was an issue on old trucks with harnesses rubbing but I can't remember the details. Anyone else?

dieseldoc · May 4, 2013

I need to look at this truck closer, but sure seems like a wire or sensor type issue. The truck worked great and than boom like you flipped a switch it does not want to move. No signs(slipping, burnt smell or look of fluid) of trans issue, just pulled up to a stop light and than the truck would not move unless you put it down in 1 or 2 on the indicator. Thanks Bruce. If anybody else has any memories on where rubs were common at on these trucks, or anything else it is much appreciated. I am hoping to look at this truck a bit closer this weekend, will report more details if I find any.

Aaron · May 4, 2013

I've seen the harness rubbed through on the crossmember from not being installed back in the factory location, also where it comes down off the frame as well.

Also a good place to look is in the driver's side firewall corner of the engine compartment for any critter dwellings, rats nests, etc.

If memory serves me rightly, I have also replaced solenoid packs for this concern.

dieseldoc · May 5, 2013

Were you able to determine the solenoids at fault by a pressure test or by electrical test? Or was it a process of elimination? Thanks for the tips guys hoping to look at this truck tomorrow and hopefully narrow something down.

Aaron · May 5, 2013

If I recall, it was a combination of electrical and pressure testing, but it has been quite a few years since I had a 4R open. The last one I did didn't back up, so the customer sent a replacement trans.

Check your powers and grounds to the trans as well, could be something like a blown fuse or something silly like that too.

Jeff Clyde · May 6, 2013

Corrosion at the bulk head connector on trans ? Have seen more than 1 transmission declared dead only to get it in from another shop to find corrosion causing the problem

mrbudge · May 16, 2013

If you unplug the bulkhead connector you will always be able to go in foreward (I believe second gear) and backwards, if your internals are ok. If not, well......

dieseldoc · May 21, 2013

Well I suggested the guy take it to the trans shop for further investigation. They determined it was hatched and needed complete rebuild. A week later and $2800 bucks he is back on the road. Thanks for the input guys always appreciated