2007 JK 3.8l 6sp manual transmission runs very hot, transmission hump noticeably hot, normal driving flat land 2wheel drive mode not towing.
fluids all topped off. Running 18” jeep wheels with 33” contis. Any thoughts why so hot?

 

It shouldn't be the trans getting that hot. Do you have your carpets out? You know the two cats get around 1500° as well and they're in prime position to funnel that heat up towards the center bump there.

 

yeah, I was just under there looking after a short drive and saw the cat converters on each side of the tranny, I dont have any carpets just rhino lining and rubber mats. I guess the catalytic converters are the heat source, dont need a heater in this beast!
thanks for the reply!

 

That lack of carpets is where you'll really notice the heat. I don't know for sure, but it may be worth looking into the BedRugs/ BedTreds floor liners. They appear to have that easy clean you're looking for but I think they also give you some of that heat resistance that you'll be looking for here in a couple months.

 

A question were the heat shields still attached to the floor above the trans ? It is possible that they might have become loose and removed.

 

Heat shields still in place, wonder if I could add more?

 

As weird as this sounds the heat was indeed coming from the rear catalytic converters near the transmission, but I just replaced the stock muffler with a dual outlet high flow unit and the heat is gone! Stopped up muffler?

 

Update, high heat came back! Have since removed the two rear cats, seemed to help at first but now the heat is back! This is unreal, after a 10 mile drive the transmission hump is so hot you cant keep your hand on it, the heat is unbelievable, this cannot be normal! Are my front cats stopped up maybe? Has anyone else dealt with this?
thanks
cam

 

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Haven't run into this problem, but perhaps checking the temp of the transmission with an infrared thermometer would help in diagnosing where the high temp source is coming from. Just a thought

 

Update: I ordered new exhaust pipes with all 4 catalytic converters, will update after I get a chance to install!
Cam