What you know about a 91 Pete

Them 425 could be bumped up to 430hp but that was the highest you could go unless you wanted to change injectors and turbo then 450hp was all they told my dad he could go. He had a T600 and was getting 6.8 to 7.5 mpg with that motor.

My buddy has that truck and hasn't done anything to the motor but change the oil! It probably has over 800,000 miles on it. The drivers he has in it aren't the easiest on equipment either. That motor really turned out to be dependable.

 

of road you want low gears and a close spread. the 9 speed has a huge rpm gap between gears. When you are rolling through the mud you want the lowest gears possible and if the gap is too big to the next gear you are stuck in that gear. A 13 isn't a great ofroad trans either. My reference would be a 15 with the deep reduction, which means you split the gears on the bottom not the top. or an 18 speed where you split top and bottom. You don't ALWAYS ned those bottom gears but when you do need them and don't have them you wil regret it while you are finding a dozer to pull you out. Logging is hard on trucks to begin with and I do realize that sometimes you just have to make do with what you have but I wouldn't use a 9 speed, they even suck ON the road. 13 you have to shift the bottom end but at least the gears are closer together

and the loggers I know don't roll around with only 85k on. you try to shift a nine speed before loosing too much road sped when you'r pulling 100k

 

Oh boy 100k....only when DOT has left the mill..........well I just found that old 86 frieght with a fifteen spd that would be ideal it's and old motor with 3406 cat it would make the perfect log truck

 

A 15 speed is the best way to go. I used to pull feed to chicken farms all around this area. Hilly, muddy, out in the woods, and sometimes a real mess. Back then they were still using multi small houses on farms that were made for straight trucks, and they were just in the first few years of using trailers.

It was really hard to get around as tight as some of the farms were. All we used were 350 Cummins, 4.11 rears, and 15 spd trans. It was tough enough in the mud with a 15 speed, it would have been impossible with anything else. They even used the 15 spd in the straight trucks.

A 9 speed is tough to deal with on soft ground, especially taking off. If you take off in low the truck stops before you get to first.

 

Thanks for your post I'lll be adding pics of that 86 frieghtliner I'mma bring from the dead

 

exactly! the old tractor i drove had a C-13, and 9 speed, once you got around 100-115K, it was really hard to get it moving, and that was pulling scrap wagons, on blacktop.

as for logging, I agree with one everyone else.. you need gears.. lost of them.

All the older trucks around here ran 425 cats, with a 8LL or a 15 speed.
All the modern trucks are 550 or 625 cats, with 18 speeds, and 4.30 gears, some running pitsburg power on top on top of that..

But then again, in MI, logging trucks are always in the 170-200K range..

 

Wow thanks for the info

 

How are you guys doing hauling them logs up north? I tried to get in on it with my trains after steel died but they closed the plant up there or whatever and couldnt get any work.

 

fairly slow.. One of my buddies sold his last winter, and and bought a 379 and a 6 axle set of trains, and is doing way better hauling steel actually..
that being said, those who know the right people are still doing ok logging.

 

Steel aint what it use to be, the heavy MI steel is almost over, they literally want you to run for free.