have been following this post because it is interesting reading. one or two posts up is a mention of 3:90 gear in a 1/2 ton rear. i have a 46 1/2 ton and believed the rear to be a 4:11. not having known of the 3:90 are these part of the AD series trucks? is there an easy tell between the two? are all 41-46 1/2 tons the same rear @ 4:11? will 390's swap w/ 411's and at a cheaper cost than the patricks 355's to get a nearly similiar gearing to mph result? i will be installing a 60 261 in my truck when she is ready. thanks folks...biged

"it's only old if you can't find a use for it; otherwise it's cool and i'll use it."