I am having the same problem... 98 Ram 1500... cruise at 70 ..rpm 1900...tranny seems to slip, lag, struggle...rpms to 2100...back...every 30 secs to a minute...dealer rebuilt tranny twice ... last a week ago 7/1... still same.. back to dealer ... they said tourque converter kicking in out... duh!!.. finally replaced tps...throttle position sensor.. is better... not right... u can still feel it at all speeds .. try maintaining 40...50 ...60 mph....Dodge has a problem here they won't admit

 

I have had a similar incident. Don't know if its the same though.

when I reached aprox. 700 miles I was driving @ around 45 mph in some what dense traffic. typical rush hour type stuff...hold at 45, lay off the gass till 40, back up to 45 of 50, repeat...for about 20 min. or so.

It started shifting into and out of Over-drive really hard, with each shift the rpm would jump and fall about 500 rpm. I guess the main difference was that my check engine light came on.

I stopped within a mile and called Dodge road side assistence to have it towed back to the dealer (gotta love the free stuff that comes with the truck). when all was said and done, the valve inside my automatic tranny that controls the shifting between 4th and 5th
was going bad. so they replaced it under warrenty and I havn't had a problem cence.

Hope it helps.

 

Change the Throttle Position Sensor.

 

Has this problem been solved? I am getting the same cruise control problem on my 02 Durango 5.9 pt4x4.

Could it be the speed sensor on the transmission?

 

as mentioned earlier it's the throttle position sensor

 

My '98 does the same exact thing. I know its the torque converter. I've heard and have done holding the brake just so the lights would come on but not actually brake and the TC would lockup. When i do it going up a slight incline then the TC will stay locked up the rest of the trip, but if I do it on level ground then it will lockup and unlock constantly. No check engine lights are on, but changing the throttle position sensor should maybe help?

 

Yeah but... if the tps is bad and sending the wrong signal back to the controller it may think that you are on the gas more than you really are, causing the TC to unlock. TPS's are under $40 and is a common problem on the Rams... change it.

 

Thanks to everyone on this thread! My 98 Ram Quad Cab was experiencing the random surging rpm's at highway speeds especially in cruise control but also without it. I had it to the dealer twice and a transmission shop once. Each time they said they couldn't find anything wrong even after I had described the situation. After scouring the Internet I ended up here, found this thread and replaced my TPS. Problem solved. Replacing it was easier than changing my oil. I'm just sorry I didn't find this info sooner.

Thanks Again!

-Flailn

 

Glad to hear it fixed your problem. Visit often & you'll find the fixes for most of the dodge problems that pop up. Also keep an eye on your gas milage, it may go up now that the pcm knows how fast you really want to go...

 

I replaced the tps sensor and my truck still does the same thing.... any other ideas?

thanks