Isx 870 with 1.2 million miles 05 international

[Izzyrod52]

The rears dont concern me too much as it's a local truck that doesn't run hard at all. I've babied it and run a nice and easy 63-65 loaded no more than 84000. Rpms stay from 13 to 14 at that speed. Gears are tall but I do mainly highways and I dont nascar with other truckers at stoplights. We have parts to inframe and we just completed our 2001 detroit 60 last year and she's running well (knock on fake international woodgrain) lol nonetheless I'd love a 13 speed on 3.36s if my wallet allows this year. I haul aggregate which is one hell of a roller coaster. Thanks for the input and keep em coming. I'm here to learn -Junior