Lock up occurs when od is on but no 4th gear
 

Please help , rebuilt trans , no 4th gear , tried the pot mod , grounding the brown wire with a toggle nothing . It did go into 4th but very randomly , seems like on really cold days before the temp gauge moved , anyone ? New overdrive switch , with overdrive on it won't lock up until about 50mph but never shifts into 4th

Anyone with any info or advice please chime in

Sounds like a TPS issue

Even with the pot mod ? The truck locks up at around 50 55 but 4th doesn't happen , just trying to make sense of it

NO 3-4 UPSHIFT
1. O/D Switch In OFF Position.
1. Turn control switch to ON position.
2. Overdrive Circuit Fuse Blown. 2. Replace fuse. Determine why fuse failed and repair as necessary (i.e., shorts or grounds in circuit).
3. O/D Switch Wire Shorted/Open Cut. 3. Check wires/connections with 12V test lamp and voltmeter. Repair damaged or loose wire/connection as necessary.
4. Distance or Coolant Sensor Malfunction. 4. Check with DRB® scan tool and repair or replace as necessary.
5. TPS Malfunction. 5. Check with DRB® scan tool and replace if necessary.
6. Neutral Sense to PCM Wire Shorted/Cut. 6. Test switch/sensor as described in service section and replace if necessary. Engine no start.
7. PCM Malfunction. 7. Check with DRB® scan tool and replace if necessary.
8. Overdrive Solenoid Shorted/Open. 8. Replace solenoid if shorted or open and repair loose or damaged wires (DRB® scan tool).
9. Solenoid Feed Orifice in Valve Body Blocked. 9. Remove, disassemble, and clean valve body thoroughly. Check feed orifice.
10. Overdrive Clutch Failed. 10. Disassemble overdrive and repair as needed.
11. Hydraulic Pressure Low. 11. Pressure test transmission to determine cause.
12. Valve Body Valve Stuck. 12. Repair stuck 3-4 shift valve, 3-4 timing valve.
13. O/D Piston Incorrect Spacer. 13. Remove unit, check end play and install correct spacer.
14. Overdrive Piston Seal Failure. 14. Replace both seals.
15. O/D Check Valve/Orifice Failed. 15. Check for free movement and secure assembly (in piston retainer). Check ball bleed orifice.

Full post can be found here 47RE transmission troubleshooting chart. - Dodge Cummins Diesel Forum

I've gone through almost all of these except for a couple , can anyone tell me where the overdrive fuse is ? I didn't even know there was one

It should be fuse number 11 in the under hood fuse block. Also, try unplugging your O/D button in the dash and see if anything changes.

I've been through the headaches of diagnosing these transmissions and have learned a lot along the way. I'll help you anyway I can, I know how frustrating these things can be.

Happy Thanksgiving!

Thank you very much and happy thanksgiving !! I'll unplug it and go for a test drive too , then I'll also check the fuse 11 under the hood , is there anything else I could do or possibly check , thank you again - Jason

Are you familiar with checking the codes on these trucks?

http://dodgeram.info/Engine-Gas/OBDI/pcm_fault_code.htm

How long ago was the transmission rebuilt? Did you have it rebuilt or was it done by the previous owner?

Here is the component application chart for the 47RE

https://cimg7.ibsrv.net/gimg/www.die...c58e14540d.jpg

I was trying to edit the above with this information but it timed out.

Are you familiar with checking the codes on these trucks?

PCM Fault Codes

How long ago was the transmission rebuilt? Did you have it rebuilt or was it done by the previous owner?

Below is the component application chart for a 47RE, it can be used to help pinpoint the source of a problem with the transmission.

https://cimg7.ibsrv.net/gimg/www.die...c58e14540d.jpg

Pay attention to the OD-4th column. For OD to function it requires the Front Clutch, Rear Clutch, and OD clutch to be on. Notice how those components overlap to the other gears. If the Front Clutch is not functioning you will not have Reverse, 3rd, or OD. If the Rear Clutch is not functioning you won’t have 1st, 2nd, 3rd, or OD. The OD Clutch however only affects OD.

If your only issue is a non functioning OD then the problem is with the components that cause the OD clutch to be applied or the OD clutch itself. Personally I believe it’s a malfunctioning OD solenoid. Check for codes using the above link and let me know what you find.

I have no codes at all , all the gears work , it locks up in 3rd I have reverse first and second just no 4th , transmission doesn't even have 200 miles on it , I had it rebuilt after I bought it , if I leave the overdrive on , at about 50-55 it locks up but it's in 3rd . I think the truck thinks it's in 4th but it never happens

Has OD ever worked since the rebuild?

Yes but it was always very Random and never consistent , and when it did go in , it would bounce between 3rd and 4th , I'd wait for it to hit 4th then throw the lock up toggle down and it would stay in

Did you talk to the shop that did the work about the problem?

Adding a pot to replace the TPS made no difference at all correct? Are you positive it was wired in correctly and that the pot itself was good?

It still sounds like an issue with the OD solenoid but I'd hate for you to spend the money on one along with new fluid just to have the same issue. So, I'd prefer to try all the "free" options first and move on from there.

I had my uncle rebuild it as he use to work for dodge , I replaced the solenoids the tcc lock up and od as they come in a pair , I'll try the pot mod again maybe a got a dud from the store thank you for all the help , how do you hook one up again and what size should I buy ?

I can't remember exactly what color wires do what at the moment, I'll check when I get home. The pot should be a 5k ohm linear taper. A 10 turn linear pot will give you a more precise adjustment but isn't required.

Well, since it already has new electronics installed I'm going to rule those out for now. Either the pot wasn't installed correctly, the pot was bad, or there is a short in the transmission wiring harness.

yes I'm gonna try the pot again , another question , I had to run out in a hurry and didn't let the truck warm up , went down the road and it went right into overdrive , but when the temp gauge moved just the slightest it stopped , could that possibly mean anything ? This has happened before and it's the only it ever goes is when it's cold out and I don't let it warm up

Anybody have any info on this ?

Check out this thread 47RE governor pressure sensor/ trans fluid temp sensor write up - Dodge Cummins Diesel Forum

Okay , another question , would the temp gauge it's self have anything to do with overdrive ? Today it was raining and it went in a couple times it's very random

No.

I would suggest stopping by an Autozone to see if they can pull any codes. If none are found then I would try to get my hands on a scan tool with live data stream to see exactly what's going on with the sensors/transducers.

Thank you for all your time and patience , I've narrowed it down to the pot and maybe a governor pressure switch , yesterday it was going in overdrive multiple times after I kept messing with the pot and letting it shift on its own , usually I manually shift it , I think the adjusting the tv cable and replacing the worn throttle cable I'll be fine thank you again as you was the only one to reply - Jason

No problem :tu:

I hope you get it dialed in and working right. These aren't bad transmissions once you get them figured out. About the best tool you can get for them is a diagnostic scanner with live data stream, they can be had for around $200-250. With one you can figure out what's going on pretty quick and eliminate a lot of the guesswork.