have 2000 ram 1500 5.9 4x4. Took my truck on a trip last week and was on the freeway at like 65mp set the cruise control and normally if i hit like an up hill or something the rpms go up a little bit as usual. This time i was driving when the truck needed to speed up instead of slow accel the rpms were jumping like 2-3k rpm in like a quick blip. Almost like when you hit the rev limiter the rpms jumped up and went right back down did this like 3-4 times until it got back to speed. Thought it was just a fluke but its doing it everytime i have the cruise on and it needs to speed up. Any ideas what would cause this? its not kicking in and out of OD when its doing this either. Ive tried it at like 35 with the od turned off and same results.

 

the tps controls 3-4 and 4-3 shifts

 

I am having an issue with my cruise as well. If I set it for 60 mph and start up a slight grade, it will get down to about 45 mph and it still won't have downshifted and picked up to the set speed again. I had it happen twice, so I won't even use the cruise anymore. I find it less annoying to just use my foot.

Would the TPS be the cause of this as well?

Ok, hijack over.

 

likely your TV cable.

locate your throttle lever. there will be a black plastic boot attatched to a stud on the lever. the boot will be attatched to a cable that runs all the way to the shift lever on the driver side of the tranny. move the throttle lever and watch the TV cable. is it perfectly in sync with the throttle levers movement? if not, push the shift lever all the way to the rear of the truck, easily let it go, does it return all the way to the front of the truck? if not your springs missing

 

replacing tps can cure some cruise control issues, especially with it not holding overdrive and not applying modest throttle to hold speed.

however, these trucks still drag down a lot on steep hills.

 

Mine did what yours is doing. I could set the cruise and it would just slowly lose speed. I had a bad cruise control servo (located under the battery, has a vacuum line running from it towards pass side firewall and cable running from it to throttle body). I replaced mine with one out of the junkyard on a hunch and cruise works great now. Sounds like your problem, or possibly just a vacuum leak in the vacuum line itself or somewhere else. Good luck with it.

 

Thanks for the replies. I will do a little checking to see if I can figure it out.

 

im not having any issues with the od holding, its staying in OD when its doing the rpm jumps, ive never experienced a car doing thing like this. Its doing it when od is disabled at like 35mph. Any ideas?

 

I had the same problem. Zman17 told me to check my plenum gasket and sure enough the thing was blown, allowing oil to get in the chamber. Pull your TB off and shine a light down in there and see if you have any oil in the chamber. I just ordered a Hughes kit to fix my problem.

 

IMPORTANT NOTE:

The user manual says to take your truck out of OD when going up a hill. Believe it or not 4th gear is a bit different without OD than with OD. Weird, but going 65 MPH in 4th without OD has more RPMs than 4th gear with OD on.

If you are going up a hill in OD, WHAT YOU ALL ARE SAYING will happen every time.

ALso, if you want to fix that. Get a SCT. Since I got the SCT, the shifting is much better with the torque management taken out!!!

Night and day with how your truck runs with and without a SCT. it goes from weird shifting to smooth shifting. Like a newer car.