got a 98 ram with 5.9, 193,000 miles. runs great for the most part but at highway speeds it hiccups over bumps. be drivin along 65 mph and every little bump it jumps 2 or 300 rpm for a sec then back to normal. annoying and a concern. is that something with the engine? vacume? or the tranny? trans shifts good and doesn't seem to slip. just on those pesky bumps. any help greatly appreciated thanks!!!!!!!!!!!!!1

 

Try replacing the TPS.

 

what is tps? throttle position sensor?

 

Sounds like the sensor in the tranny. Mine did the same thing but once I got the tranny rebuilt the problem ceased.

 

yes, throttle position sensor

 

the 300 rpm change is the torque converter lockup clutch, TCC, unlocking and relocking.
it might be the TPS. if not, check where the electrical connector plugs into the trans, and check the wiring for damage.

 

My truck would jump up randomly about 300 rpms on the highway. It had nothing to do with bumps though, I replaced the tps and it hasnt jumped since.

 

i replaced the tps last weekend and it totally fixed the problem!! thanks guys!!!!!

 

Awesome! Thanks for letting us know the fix. And btw, Welcome to DF. Now don't be a stranger.