Hi Folks,

I have a 1998 Dodge Ram15004x4 Quad Cab. It has a 360 and a 46RE Transmission. The truck has about 117,000 miles. I got itabout 16 months ago and I have only put about 5,000 on it. I have no idea of the history of the truck or the transmission except that I recently changed the tranny fluid (ATF +4) and filter.

The check engine light is on and the code is P0783 which indicates a 3-4 Shift Malfunction. It will not shift into 4th gear (overdrive). The Dodge Service Manual indicates that for No 3-4 Upshift, it could be any of 15 problems from a blown fuse, to a clutch failure. The OD Override switch seems to work. When I push the button, the O/D Off light comes on. When I push the button again, the light goes away.

I've taken it to a couple tranny shops. They are more interested in rebuilding the entire tranny than they are actually finding what the problem is. I can accept that it may need rebuilt. However, I'd like to make sure it is not a minor electrical problem before I fork over a couple grand. I lost some trust in the mechanic when he told me I should be getting 19 - 20 MPG instead of the 10-12 I'm getting now due to lack of overdrive.

Could it be a wiring problem or a solenoid or a fuse ? Is there any testing I can do myself ? I've got basic skills, basictools, some electrical testing equipment, and plenty of time. The purpose of the truck is simply to haul my toys around so this truck isn't something I need every day. For the short term, I just want the check engine light to go away so it will pass PA inspection.

Other than the overdrive issue, the tranny is fine. It shifts smoothly when it should. No leaks, noises or other problems. When I changed the fluid there were no shavings in the pan.

Thanks all.

Bob Elliott
Central PA

 

What it sounds like to me is you have a selenoid that is sticking /bad......

 

I don't think you will be getting 19 to 20 mpg's atleast not a CC 4x4 1500 more likly 14 to 15 maybe 16 on a road trip. Maybe some trash knocked loose when fluid was changed? what color was the fluid when changed if black then you had alot of tarnish...Goodluck...

 

Its the solenoid, I'm not sure but I think it is something like the tcc solenoid, not positive though. There is a little spring in it that will go bad causing it not to shift from third to fourth, my father had this problem in his 98 and just rebuilt the solenoid with a kit from the transmission shop and has shifted like a top since.

 

You can band-aid it by replacing the selenoid pair (the tcc selenoid and od selenoid are on the same bracket) and the govenor selenoid and pressure switch. You have to remove the later to access the former anyway.

I would CAREFULLY check the fluid you drain at this point. Any metal shavings, brown lining or excessive sludge would indicate eminate failure.
Based on your tranny's mileage, and the fact you didn't specify any mods like coolers or temp guages, I'd say your tranny is about to take a *%#@. If it makes you feel any better, I just had mine done at 118K. It wasn't cheap, but it was worth it!

 

Thanks for all of the replies. Since the truck had 113K on it when I got it, I just assumed that the tranny had already been rebuilt at some point. The filter was encased in some stainless steel housing so I know it was an aftermarket, improved filter.

I've had two tranny shops tell me that they would replace the solenoids, but that would not fix the problem. Yet they give no indication why they know the problem is not a solenoid malfunction. I guess I just don't trust any of the shops I have talked to.

Thanks again.