Vehicle: 2009 Dodge Ram 1500 5.7L

Problem: The transmission for the truck keeps entering limp mode and getting stuck in 4th gear. There are no engine codes according to a scanner. I installed programming from a Superchips flashpaq and have gone through all of the tunes and currently it has the stock tune installed on it. I would say this problem started after Superchips was used but the truck has been sitting for about two years and was just started up after installing the tune.

Now what happens is a little unusual compared to other problems with the 4th gear issue. When I program a tune into the truck at one point it directs me to cycle off the ignition and then turn it back on so that it can clear DTCs. Once the tune is finished installing I can start the truck and the transmission will function just fine. But this only happens if I go from the On position to start in the ignition. If I turn the key off and back on it causes the transmission to enter into limp mode. If I drive the truck after I immediately start it, the transmission is fine. If I turn it off and try to start it the transmission locks into 4th gear. If it sits for a long period of time it will act normal the next time I start it. If it was previously working and I switch the ignition to ACC and try to start it, the transmission messes up. Essentially, if I turn the ignition to ACC or off the next time I turn it on, it is messed up.

One thing I have noticed is that the Trans Temp readout is showing "---" when the transmission is in limp mode. When the transmission is functioning correctly the temp sensor shows valid data but it displays "---" when it is messed up. From my understanding, when there is an error in the trans temp system it uses a calculated value to determine temp. This leads me to believe that the problem is not with the sensor but that there may be some sort of programming problem in either the TCM or PCM. I also don't believe the sensor is the problem because the issue occurs as soon as a particular sequence happens. Turn it on immediately after programming it is fine. Turn it off after programming or any other time then it messes up.

I have done a PCM reset, used every tune on the Superchips program and reverted back to stock, and the fluid level in the trans is normal. Curious if anyone has experienced this or has input on what the problem might be.

Thanks

 

I am not sure if the hemi is anything like my Diesel,,, but when the temps are cold like they are here, the computer locks out overdrive till the trans temp reaches normal, I noticed my 09 Hemi yesterday that when it sat outside and it was -19 F here the truck would show in 4th,, couldn't go up or down or even get it to show D on the dash. This morning after sitting in garage the trans will shift like normal. SO it makes me think that when cold the computer locks out overdrive. I may be wrong on the hemi, but I know the diesel does this for a fact as the guy that built my trans for the diesel said that's how the program is designed, and once it reaches normal temp, it will go into overdrive and function normally

 

I had an intermittent limp in problem with my 2012 that turned out to be the solenoid pack. It did set a trouble code each time it happened though.

 

Have you checked all of the fuses in the PDM? If the IOD fuse is open it can/will cause the transmission to go into Limp Mode.


regards,
Dusty


2014 Ram Big Horn 1500 Quad Cab2WD, 5.7 Hemi, 8HP70, 3.92 LSD, factory dual exhaust, 20” wheels. Now at:050943 miles.

 

Limp as in truck goes into limp mode? Do you get a flashing throttle warning on the dash display?

 

Mine too was in limp mode. It would stay in limp most of the time but would kick off once in a while after backing up. Replaced the solenoid pack for 400$ at home, instead of paying the dealership $1000. These computerized vehicles just aren't worth the headache any more and these little parts break down at the worst time.

 

So I thought I'd resurrect this just in case it might help someone else.

I service a '12 Ram 1500/5.7 and it was going into limp roughly every 3rd or 4th drive into town (about 30mi one way).

I searched the web and of course suggestions were all over the place. However one disturbing theme was people who had done solenoid packs, torque converters and even entirely new transmissions only to have the problem stick around.

Another theme I saw was that it could very well be electrical, wiring or grounding related.

So, in the spirit of K.I.S.S. I did two things:
1) unplugged and reseated the big plug at the solenoid pack. Now, it seemed to be seated quite well but I figured WTH, it's easy and free. I also looked for pins that might be pushed in while it was apart, but saw nothing of concern. Compressed air recommended to clean the area BEFORE unplugging because it's effectively a shelf up there that holds dirt. And be sure you don't INTRODUCE dirt before plugging it back in.

2) ran a fairly heavy gauge (12ga or 10ga maybe?) ground wire from the right side engine head to a ground terminal on the right fender. Interestingly, I did note a partially burnt-through factory ground strap near the right EM (exhaust manifold). The damaged strap was only easily visible from under the truck and it just clipped on the tub/cab at a sheetmetal pinch seam or fold. Now I don't think this ground strap was ever particularly important because of it's nonchalant method of attachment, and theoretically it was still providing a ground because it was only 60% burnt through. Still, I figured additional grounds can never really hurt anything so long as you're not (or I'm not, rather) dumb enough to create a direct short.

Anyway, after doing these 2 things the problem has not returned for over three weeks, so I'm cautiously optimistic. I was pretty sure it wouldn't do anything and warned the vehicle owner (a non-profit for whom I volunteer) that the next step would likely be a solenoid pack.....but I didn't want to spend several hundred on a pack and new fluid if not necessary. On the bright side since i work for free they can't ever complain about my fixes -- or lack thereof!