The automatic transmission in my 1995 RAM 2500 appears to slip sometimes, it happens at highway speeds (65 to 75 MPH). It only seems to do it for a second or two. This has just started to happen and so far has only done it 3 or four times. I'm not a mechanic and will have to take it to a shop to get it fixed. I'd kinda like to know what it might be so that I don't get ripped off. I'd hate to buy a new Tranny if it just needs an adjustment or something like that. Thanks for any help.

 

I wouldn't call myself a trany guy , but these trucks have a weak trans as far as matching up to the Cummins , one of the 1st is the torqu converter , there are addjustments that may help [ do a search here ] to find info to do it yourself , the only special tool required is a inch pound torqu wrench ,
We're talking about the 1st mod that you want to do if your going , if you are going to add more HPs , then gauges.
Then your hooked-horse power junky-

 

my 95 has a really bad stock torque convertor. It couples poorly at low speeds and the TCC engages/disengages frequently if you hold it near 60. The only things I can suggest are to check your oil quality/quantity and your TPS.
You might also look into installing a lockup switch to see if you can keep it in lockup on the highway.
Regardless even with stock motor and pump Id look into rebuilding it so it doesnt implode in the future. Theyre notoriously weak.

 

you likely are getting converter unlocking and then relocking, check TPS, trans temp sensor, brake switch adjustment, and finally if that doesnt take care of it test the alternator and install a noise filter in the TPS signal wire and isolate the alternator field wires from the TPS signal wire.