2003 1500 4.7l 2WD 66,000 miles.
Recently, at speeds just above the overdrive setpoint, I notice my RPM's are jumping 300-500 then back (usually 1700-2100rpm). It happens on level ground, with cruise on or off. It happens about every 30 seconds or so. I can't tell if the trans is actually shifting, so that's not real obvious. After a 20 mile ride, mostly highway, I stopped and checked the trans fluid. It wasn't overly hot and didn't smell burned, but it didn't smell normal either (might just be my imagination). I bought it with 48,000 miles and I haven't changed the trans fluid yet.
OK, so that's the info, now for the questions;
Could this be a sign of trans issues? Should I change the fluid? Could it be a speed sensor or some other switch issue? Thaks for your help.

Dan

 

After further research, it appears that these trucks are notorious for bad throttle position sensors, which cause the problems I described. So, as soon as I can that I will be replacing it.

 

I've had a 2007 and now a 2008. And they both do it. And the dealership mechanicsdon't really know. So, I don't know if it's because they don't know or what's going on. One did say it was the MDS. But why would it continually do it. It acts likes it's "hunting" for the right position to be in........

 

danmac520...this sure sounds similar to the issue I'm experiencing with my '08 hemi. There is another active thread about "RPM hunting with cruise". The common theme seems to be related to the MDS...however your 4.7 does not have MDS...so this leads me back to possible issues with the torque converter lockup and/or the throttle position sensor.

 

I replaced the TPS and it did the trick. The RPM's are now rock steady and actually a little lower than before. $44 from Auto Zone and 30 minutes to replace. Thanks for all the input.

 

Hemi's don't have a TPS. And yes the TC does unlock when MDS switches in order to help mask the change over. Like in the other thread...mine has done it since new and so has every other MDS ram i've driven.