I recently purchased a new RV and am having tow issues can't seem to find a sweet spot my old rv was 2800lbs dry weight and towed beautifully the new one is 3800lbs and my truck seems to be searching for gears between 60-65mph will constantly shift in and out of Overdrive I'm afraid it's going to burn up. I have a 3.93 posi behind a 5.7 Hemi. Is this normal ? I also have a 3.53 rearend I am thinking about installing I know I will loose some zip but hope to gain some mpg while towing. I flushed the trans when I installed new end flushed converter and installed a new solenoid pack it does not have any slipping issues just searching for a gear any help would be greatly appreciated. Also are there any mods I can do to help it while towing ?.

 

Do you use tow/haul? Depending on tire size you may need more gear. 3.53 will make it worse. My 04 I had it regeared to 4.56. You will not get good fuel mileage towing. I usually got 5-8. 2200 and up is the sweet spot.

 

Yikes that sucks running 18s now my posi is shuddering .