Bullfrog, I added a auto trans cooler, leaf springs helper. It does help. I went up good little hill 1020 feet going 50mph as that it was curvy before that and it pulled it down to 40mph. Not bad, I think. Another hill I was going 70-75mph to get up a little hill and it only pulled it down to 60mph. I don't push the truck. The temps were in the high 80's, I did see the temp gage go up a little but nothing to be concerned about so far. I know to take it slow and try to go when its not hot out to help the old girl (truck) :-}