I’ve got a 1999 Ram 2500 V10 with an autotrans with factory over drive (OD). Over all the truck runs great. Lately while towing (7500-lbs) the engine will surge 200 to 400 rpm when the OD is off. Prior to this the transmission speed sensor was replaced (1800 miles ago). I’ve take it into a good transmission shop and they adjusted the TV or CV cable (not sure name) and no charge. Truck has nice crisp shifts in all gears OD on or off but I’ve still got the surging problem. My gut feelng is that it is not the torque converter but something electronic. What do you think is my trouble (besides a truck that gets 11 mpg and 6 when towing).
I should mention that I bought this truck and a toyhauler, used, as a gift to myself after serving 14-months in Iraq and Kuwait. NO MORE TENT CAMPING FOR ME!!!
It sounds like the converter clutch is falling in and out of lockup. Several thing can cause this, the number 1 thing I have come across is a faulty TPS (Throttle Position Sensor). A few other things I have found on these transmissions is a faulty, leaking trans temp sensor, and noise coming from the alternator. I would address the TPS first since it is the most common.
transman
When the OD is “off” the converter will lock up in 3rd gear. When you crowd it {press on the gas} the converter will unlock and cause an increase in RPM. Could this be your problem?
I probably should have told you from my previous post that the TPS can be checked by scanner for voltage spikes and flat spots in the sweep. In these transmissions, we have found alternator noise spikes in the TPS signal to the PCM. The spikes have been wreaking havoc in the TCC and the O/D circuits mainly because those circuits are electronically controlled. The more you tax the alternator, like with A/C, headlights etc. the more chance you get the spiking in the circuit. The main reason for this is all because Dodge has run both the TPS and the alternator wiring in the same harness. I have personally opened up this harness and separated the TPS wiring from the alternator wiring to cure the spiking. There are noise filters out there in the market right now that addresses this problem. Another thing to check first is all grounds, including the battery cables for corroded or bad connections. As far as the trans temp sensor goes, the easiest way to check this is to pull the electrical connector off the sensor and look for any ATF dripping out of the electrical terminals on the switch. If its wet, replace the temp sensor.
transman
would this also apply to a diesel? i have a 2002 ram 2500 diesel and am having similar problems with torque converter and whatnot. at around 35-50 mph, the engine surges 200 too 400 rpm. something with the lockup of the torque converter clutch. does this with overdrive on, doesn’t do it nearly as bad with overdrive off. i did take it to a transmission shop a while back and they cleaned the transmission lines and battery terminals and it fixed the problem for about 200 miles. ever since then the problem has been slowly worsening so now its back to how it was before it took it in to the shop. thanks in advance.
Yep, it sounds like you are having the same issues. I would have a trans shop check all things I listed in my previous post. This was a common issue in these Dodges.
transman
I had the same problem with my 1995 Dodge Ram 2500 Diesel with auto Tran. After two TPS at about 150.00 dollars a piece, it had to be a better solution. The answer disconnect the TPS and attach a potentiometer to it, you will dial at what speed you want your OD to kick in, works great and no more surges or going in and out of gear. The kit is about 35.00 from DNR products and only about half hour install time.
Good luck.