HemiJKU

So I've got a 2010 Jeep Wrangler Unlimited that I did a 6.1L Hemi swap on about 4 months ago. AEV's kit calls for the use of the 545RFE Transmission (I got mine used with less than 40k miles out of a 2010 Jeep Grand Cherokee 5.7L Hemi). Within the last week I was experiencing some VERY strange transmission issues but there are no lights on, on the dash and when I hook it up to a scanner it doesn't give any codes.

So starting about a week ago my transmission started doing funny things. Typically at 50 MPH it would be at give or take 1,500 RPM's but when I first started experiencing these problems it would be at 2,000 RPMS at 50 MPH and when I got on the skinny pedal to accelerate it wouldn't downshift. For the first 2-3 days I started having these problems I would turn the truck off and turn it back on and it would drive normal for a while and then do it again. I checked the trans fluid and it was fine but I flushed it anyways and it was good for a day. The next day after the flush it started doing the same thing again but this time it felt like it was hunting for the right gear rather then just staying in the gear it's in and not downshifting or upshifting. In the days since it's gotten really bad, yesterday I'm driving along at 40 MPH and it downshifts to what I can only assume was 1st gear because my RPM's shot up to 5,000-6,000. I stopped, turned it off and turned it back on and it was fine for about half a mile and then back to 1st gear. Now when I take off it just wants to stay in first gear and won't upshift. If I go REALLY easy on it, meaning taking 30 seconds to get to 40 MPH it does OK but still searches for gear.

I'm really starting to think that the trans itself is going bad but there are no definitive signs and no CEL or any codes still. At first I was thinking of replacing it with another used trans but I've only put about 4,000 miles on this one and I can't afford to be changing my trans every 6 months. I'm leaning towards having a local shop, one that was recommended to me by a guy I know that builds performance cars, to have it rebuilt with beefier parts. He will guarantee it for 12 months/12,000 miles but I was hoping maybe someone here has experienced something similar or maybe have some information to help me because at this point I don't even know where to start.

Thanks in advance for any and all help/suggestions!

bazillus

I've got the same transmission, but from factory, running the 2.8 CRD. Transmission has done 210.000kms yet.

Mine was doing funny things when the TIPM went south. Won't allow me to shift into Drive and later on it was hunting for gears like you discribed.

Check your wiring, especially from trans to PCM and from the shifter to the TIPM.

I doubt it's a mechanical problem when the trans fluid looks like it should and the level is fine.