Got a 2003 4x4 with 4r100 trans. When I really stomp on it, to pass someone for example, as the RPMS increase past 3k, they will drop about 200 for a brief moment, then pick back up. is this a sign of trans slippage? I've never experienced this in a vehicles before as this is my first automatic trans I've had.

 

I would look to the fuel system maintenance and spark plugs/air filter first. Also check for a loose vacuum hose/leak. A pause when asking for passing gear is a normal event. The trans has to shift, after shifting it will run thru the RPM's and then shift up & return to overdrive. One way to get better performance characteristics is to shut down OD, like in hilly areas where you need to pass quickly to make it back in before the yellow lines. Mine has trailer tow and M to fine tune the performance needed. M is like having a manual 6 speed, with tight hard shifts. If you experience shifting pattern causing slipage, and increase in RPM's without the go/go then you are suffering a trans malf probably. It will rear its ugly head accordingly. Hope not, pull the trans pan and trany valve, service it checking the trany valve for loose broken parts. These will bring about extreme trans discomfort, and lead to disfunctional trans.

 

Thanks for the response, it really helped! I wasn't thinkin out of the box, ir could very well be one of those other things.