So I got my first jeep Friday and I've been driving it daily, and I've noticed that sometimes it won't go all the way through the gears and the check engine light comes on and sometimes it'll shift like it should and the light goes off. I figured it may be the trans filter, any ideas?

 

Low fluid?

 

I bet you're running low on unicorn farts, you need to check those!

 

Sounds like a low fluid problem?

One question I have is whether to go with Dex/Merc or ATF+4 when you need more. I've heard there was a mix up between the two or something.

 

I checked the fluid and it's full and clean, anymore ideas?

 

What is the code from the CEL? Could be a bad TPS.

 

I haven't had a computer hooked up to it yet cause I just noticed it yesterday, I'm really hoping its something simple like that though