Engine/Transmission (1994 - 1998) Auto Tran - no 1st when hot

[corprimo]

When towing our 30 ft. 5th wheel through city traffic, we sometimes encounter a situation where we stop for a red light, I manually shift into 1st, and the transmission goes into 2nd instead. If I catch it, I can get the transmission to go into low by turning off ignition, restarting th engine and it works just fine. This is rather awkward in heavy traffic however. Anyone know the cause and the cure for this one? Would an extra transmission cooler help?

 

[mstimac]

How hot are you talking? I'm no transmission guru but it sounds like your transmission is going into "limp" mode. Could also be the governor pressure sensor or solenoid.

 

[Snow man]

Your in limp in mode,get it fixed asap,starting off in limp in will kill 3rd gear clutches ,almost immediately.

 

[corprimo]

So what causes "limp mode?" I've got a BD torque convertor and valve body, extra deep transmission pan and Amsoil ATF fluid. It only happens in stop and go traffic - transmission temp approaching but not over 200 degrees. What's the fix?

 

[mstimac]

It shouldn't go into "limp" until the trany hits a specific temp, it's something around 260 or higher. Not positive. Mine was doing the same thing and a governor pressure solenoid fixed it. Took me all of an hour to change.

 

[illflem]

There is no limp mode on a 12 like a 24, just the transmission won't go into OD lock up if the fluid is too hot. You've got a transmission problem that probably isn't related to the electronic heat sensing controls.

 

[JohnE]

12 valve RH transmission have no limp mode

12 valve RE transmission have limp mode. That's why those with jacked line pressure may need the resistor added to the governor pressure circuit to prevent limp mode.

Governor pressure is my first choice, too being you can clear it with a restart.

 

[vssman]

I suspect the governor solenoid / transucer is seeing too high of a pressure when you come to a stop. That will cause the truck to go into limp mode. As mentioned earlier, a resistor usually corrects it. I would suggest trying a variable resistor that can be set with a 10M ohm voltage meter. Also see if the PCM has any other codes. Mine also needed a resistor added to the water temp sensor.



So, how long did it take you to get through the intersection starting in 3rd with a 5th wheel?

 

[mstimac]

My bust. forgot the 97's had the Rh vice RE. Still I would think that the Governor pressure is causing the problem.

 

[corprimo]

I talked to my friendly transmission shop guy,and he immediately said that 97's have no limp mode. He's thinking it's a solenoid problem. I never get this symptom pulling my little lake boat or double snowmachine trailer - only the 5th wheel in stop and go traffic.



How long does it take to get rolling in 2nd gear - not too long. Only time it really was a problem was coming up a very steep hill near our house and catching up to a full cement truck. I tried gearing down from 2nd to 1st and nothing happened. Had to stop on the hill with traffic behind me, turn off ignition, restart, and then get moving again on that steep slope. With 3. 54 gears, even in 1st, that's a heavy pull - ouch.



Truck goes into the shop on the 17th, estimate is $500 or so - any other suggestions to share?



(Next Ram will be a 6 speed!!!!)

 

[Mesenbrink]

94-95 = RH

96-early 03=RE= Limp Mode

 

[JohnE]

At least we agree it appears to be a governor pressure sensor failure. That is a relatively easy and inexpensive fix.



I re-read your signature. Have you considered a governor spring kit (gsk) to extend your rpm? I found it comes in handy on those "I really need more power plus a little extra" situations.

I can manually shift out of 1st at 3,000 rpm and that drops me back into the power band for 2nd.



-John

 

[vssman]

Hmmm,



My Dodge service manual lists all 96 & up with 47RE (not 03 models). I'd suggest a second opinion.

 

[bigkavr]

I had the same problem on my 97. Every 6 months or so I had to change the resistor on the orange wire or it would go into limp-mode at the most embarising moments. (ie, pulling the airboat up the loading ramp) I finely got a DTT adjustable voltage regulator. PROBLEMS SOLVED!!

Stupid me, I should have got the adj. reg. many moons ago.

Installation time was about 15 minutes, and 8 minutes of that was removing the aftermarket air filter assembly.

One of these days, I will listen to Bill K. when he "yells" at me the first time.

 

[corprimo]

follow up

Thanks for all the input! I spoke with Bill K. at DTT today and ordered a voltage regulator to splice into the orange wire (pin 31) and will give that a try before bringing the truck into the transmission shop. Hopefully, the cheap and easy way will be the fix that works!