'02 transmission issue

[mxmedic]

I have an '02 Ram 1500 w/ the 5.9L, 4wd, auto tranny. The truck has 82000 miles.

I have never had any sort of transmission problem with the truck. I had full tranny service (fluid, etc) about 6,000 miles ago.

Last week I started to notice, while driving down the highway (65-70mph), that the RPMs would randomly jump from about 1750 to 2000-2200. That lasts for a second or less, then it returns to normal. I am driving on flat ground and not trying to accelerate or decelerate.

The tranny fluid is fine--I checked that. The problem seems to be getting worse. I can feel it when it happens, and my husband also felt it before I had mentioned it to him. It seems to do it more frequently and slightly more drasticly than initially. Like I said, the transmission has never slipped or anything before. I thought maybe it was the overdrive switch, but it still did it when I turned the overdrive off. I have also noticed it does it at lower speeds/RPMs too.

I was thinking maybe less an actual transmission problem than a shifting controller problem. Any thoughts? Thank you.

[wafrederick]

Is the service engine soon on?If it is on,the computer sees a problem.There are two solenoids in the valve body that go out and that is a common problem with the torqueflite 727.

[troy1]

Might be a bad TPS. You need to take it and get it scanned.

[mxmedic]

Thanks for the replies.

No, the SES light is not on. If the light is not on will it still give codes if it is scanned? Also, would bad solenoids or TPS make the SES light come on?

Thanks again.

[HEMIDAZE]

Don't know why but these trucks have an issue with the torque converter clutch kicking in and out. The sensors (or what ever tells it to lock) can't decide to lock or not. The next time it does it step on the gas a little and I bet it will stop.

[RexNfx400]

There is a few reasons for this. A/C ripple in the charging system is the biggest, which effects the TPS signal. Just depends on how bad the symptoms occure. You have to make certain the computer is "commanding" the in/out surge. This is done with a scanner and monitoring live data while driving and symptoms accuring. There are usually different reasons for the problem. A few different things that can fix this. A new alternator, battery/s, a RFI noise filter http://www.transbuilder.com/z-store/glaenzer-info.html , pressure washing the engine on gas models help too. There is a process of elimination to diagnose this. It fairly time comsuming. Or, otherwise you just keep throwing parts at it. The most important first step, is to see if its commanded by computer or an actual mechanical malfunction by monitoring the computer data...

[tabernacle tranz]

one of the problem are where the ground bolts to the block ,when the motor was put together it was painted before anything was installed , so where the ground strap bolts to the block,try removeing it ,wire brush then reinstall. most of the time that repairs the problem. or just indtall a new ground from the battery to the bellhousing of the trans. try and let me know how it works if not i have some more for ya