I am only towing about 4300 lbs with my burb, and have made it cross country for the last five years - but any kind of 5% or higher grade, or long 4% - and I have had to stop repeatedly to let tranny cool down when it reaches 221. And that is with an add-on trans oil cooler. This year I finally killed it and replaced the tranny with a re-manufactured one, and they put a new add-on cooler in the process. Took it for a trial run across Texas - long, flat hot run and was disappointed to see the tran temp reach 220 on flat ground, and that was with the camper pretty much empty (3100lbs +/-)

Now I'm faced with a dilemma - after sinking $5k into the car, do I try to make further modifications to help it - or bag it for a more powerful vehicle and take the loss. Would changing out the rear axle be a viable or cost-effective modification? Are there better ways to cool down the transmission?

Thanks in advance - my apologies if this is in the wrong place, I'm new to the forum