[bwood]

How many miles on the trans? Before I went to the trouble to convert over to the 80E, I would look into beefed up 60E made for towing. This way its a direct bolt in. I also have 3:42 in my truck and it is pain to pull much more than my bike trailer. My friend has the same truck as mine with the V6/auto with 4.10s (I think) and it will pull better than mine. Of course mileage isn't as good. We used his truck and my trailer while I was putting a new engine in mine. It does sit higher in the RPMs, but it gets down the road without excessive shifting with it in 3rd/OD. He pulls like you do, OD on flat ground and 3rd everywhere else.