New to the forum, a little about me- custom dry manure applicator. I'm putting together a side dump rig. I already purchased the trailer. It's a 2012 jet triple axle. Now I need the tractor. I found a 2008 Mack cxu613 with a mp8 that Mack will allow me to turn up to 450 HP. It has 12 fronts, 38 rears(Mack), 417 gear ratio, and an Allison 6 speed transmission. Truck has 700,000 miles. Most trips will be under 20 miles on both gravel and busy highways. I'm concerned that 450 HP isn't going to be enough on soft roads and getting up to 60 quickly on the highway. Mack won't let me turn it up to 500 which is what I would prefer. My dad has a 99 Pete with a 476 c15 and 13 speed for his rig and he would like more power. Any info would be much appreciated. Sorry for the long post.
You'll be surprised how much an auto makes the truck accelerate better with less power. You will notice the lower power when you hit a hill though. Best bet to try it. Short runs like that though. I say Auto for sure
We ran end spills and transfer trucks grossed at over 100K for many years with 425 hp CAT 3406's and thirteen or eighteen speeds, even the odd fifteen. They got the job done just fine. 38 rears are light, but Mack makes good stuff, they may live.
Welcome to the Forums Farmall fan!:drinkup I had a Granite with MP7 405 with Allison 6 speed - the truck was a hoss. It was a tri-axle dump that loaded, grossed 84K which it handled with no problem power or transmission wise. Regularly pulled a 54K tag trailer with either a 315, 953 or D6N on it. I took a Kobelco 160 to the coast once and ran as fast as I felt comfortable, average 70 MPH. If or when I get another tri-axle it'll have an Allison 6 sp with 400 horses, it's all I need.