I have a 98 3/4 ton Dodge diesel truck w/116,000 miles. A few days ago I began to notice at 45 mph that the tranny would slip in and out (of overdrive?) I called the Transmissionman here in Flagstaff Az. (Very skeptical of trans shops here in town) He told me that I need a new alternator, that he's seen this on at least 10 Dodge trucks in the last few mos., or that he could reroute another wire from the alt. to something else, to bypass something with the sensors. He said there is a TSB written on this. The Dodge dealer told me he didn't have time to check on the TSB, but he'd never heard of it, and that my trans. probably needed to be replaced. Has anybody ever heard of this before?

 

Yes, common problem with the electronically controlled 47RE transmissions.

It's not so much an alternator problem as just electric noise in the wiring.

Try cleaning your battery terminals, body grounds, and PCM ground.

If that doesn't fix it, come back and we'll find some more solutions before you go spending $$$ per Dodge.

Oh, welcome to the board.


phox

 

Is it 12 valve or 24?

My Dad's 24 valve had the same problem twice. The first time I just cleaned the battery cables and did the apps reset, worked fine for a year. A few months ago it started acting up again, did the same procedure but it didn't work this time. Did a search on this board found out about the body ground on the passenger side behind the battery, cleaned it and. Also ran a direct ground from the pcm which is also on the passenger side firewall, to the negative battery post. And finally shielded the heavy ground wire fom the alternator by wrapping it in foil and attaching a wire to the foil and the negative battery post. So far so good. If you need pics let me know I can take some for you.

My 97 (12 valve) started acting up last fall. I took off the tps and melted a hole in the case with a hot nail, sprayed in switch cleaner and coverted the hole with a piece of electrical tape in case I need to do it again. It's been fine since.

John F

 

Thanks guys, its a 24 valve. I'll definitely give that a try, but what is a PCM ground?

 

PCM = Powertrain control module; the brains of the power train.

If the grounds go bad (loose, rust, corrosion, broken wires) would create noisy and/or intermittent ground problems. They could also be tied to vibration; i.e. when you reach a speed/rpm combination, the grounds become loose / intermittent and cause the shift problem.

HTH

Tony

 

The pcm is he aluminum box attached to the firewall with two screws. I removed the screw closest to the engine, cleaned the surface under the screw head and attached a wire to that screw and the negative battery post. When cleaning the body ground behind the passenger side battery, I sanded off a little of the paint so there was a better connection. Use dielelectic grease to keep things from coroding.

Good Luck

John F

 

Try wrapping the black and tan wire going from the alternator to the passenger battery in aluminum foil. Solved my problem.

 

The alternator is a possible cause, but before simply replacing it, disconnect it electrically from the system by unhooking the two small field wires from the back of the alternator, then go for a drive. (remember that your alternator isn't charging now, so keep your use of electrical accessories to a minimum- lights, blower, etc.) If your problem is still there, the alternator isn't at fault.

Personally, after cleaning all grounds and battery connections, I'd do the reflash from Dodge. If that doesn't work, come back and ask about the ATS fix. I used that on a stubborn one and it worked great.

 

With those miles I would pull the alternator and replace the brushes and clean the commutator with some emory cloth.

Follow Big Blue's advice, but also follow the wire noted and it will lead to a connector. Cut that connector out and SOLDER AND HEAT SHRINK the wire back together.

Torque fan also has some good pointers. Have the JTEC controller part number checked and updated and as he stated.....BE SURE THE BATTERYS ARE IN GOOD CONDITION AND CLEAN CLEAN CLEAN.

 

i HAD DODGE RE-FLASH THE pcm BACK IN 2001 and everything's still fine.

 

Thanks again and again, but now what is a JTEC? , and what is a reflash and how do you do it? This site is amazing, I love to do my own work on my truck, I just can't always find the info on how to do it. Thank you

 

The JTEC is the name for the engine control computer (Jeep/Truck Engine Controller). The "reflash" is a new program written for the controller by Dodge, in order to fix a known problem. It's about the same as a Windows update from Microsoft. Anyway, manufacturers use Technical Service Bulletins to let technicians know how to diagnose or repair a common vehicle fault. Dodge has issued a bulletin for your condition which states that they have new programming to "dampen" the APPS sensor's signal, which "may" repair or help the condition. The reflash must be done at a dealership.

Welcome to the site.

 

I should clarify my last post. On a 24 valve truck, there are two controllers- the Cummins ECM, which is mounted directly on the side of the engine, controls the injector pump and the actual running of the engine. The JTEC is the powertrain controller, which controls the "Dodge" part of the truck (auto transmission, cruise control, charging, etc.) It is located on the firewall, behind the air cleaner.