Gear ratio over drive or direct for heavy haul up to 110K?

Against my better judgement I'm going to give my opinion. You have gotten alot of very good advise. There isn't a single true heavy haul truck out on the road that runs the ratio you want to run for a reason.....it doesn't work. I know from my experience the highest you should go is 3.55 behind an 18 spd. And you still will have issues with that. I ran 3.70 ratio for years on 40 rears. And every two yrs on average I was rebuilding one rear or the other. Getting 6 mph pulling a heavy load isn't going to happen. You may squeeze 5 mph if you baby it. I average 3.5 to 4.2 at 140000 lbs or more depending on the teraine I'm running in. Running the ratio you want to run will eat clutches, through shafts, drive lines, and bearing and gears. It will cost more in repairs than what you think you will save in fuel. Please take the info that people have posted here, it is from experience not from a dealer factoring out of a book.

 

I have 4.10 ratio and was able to get 3.5 mpg average at 200k traveling on I-90 MT, ID, WA, never below 10th gear. I think I was getting good fuel "economy". I always try to factor fuel into my rate about $1 a mile just for the fuel, that why it doesn't concern me too much. Yes, savings a good but I think it is important where you apply them. If you want fuel economy why not look into 4 speed aux trans, in 4th gear you will have better mpg, and you can have 3.70 or even 3.90 and still get good mpg.

 

STOP . STOP . STOP



listen to what people are telling you .
Get ready to get pissed off , because I don't care about snowflake feelings .
1 . 110,000 in Canada is NOT heavy haul when super bs run at 140,000
2 STOP listening to the #### dealer . Has he ever drove a truck ?
I can read any piece of paper too .
3 . Your doing oversize work at 110,000 lbs in B.C ,thinking of going to 130,000 lbs ...
Your worried about that crap that comes out of k.r mouth about overdrive's and the drag of the gears . Think about that for a moment .I hope somebody will come on here and expain that in better detail .
That was 20-30 year old technology.
Same thing about running low rpms .
3. Build a truck to do the job.

If you want better feul milage
1. Gear the truck right .
The only ratio that starts with a 3 is 3.90 on 22.5 NOTHING lower or higher depending on how you think about it .
2. Drive the truck right .

Now to recap
Gear the truck to PULL and back out a little on the hills and you will get better feul mileage and STILL out pull the other set up . Make sense ?
These guys have told you this 20 different ways .
The way I see it , here is your options...
1.Go pull a van and buy in to all this crap .
2. Do it your way , lose a crap load of money and have a crap load of break downs .
3. LISTEN to the answers of the question YOU asked by guys that have done this a very long time and build a good truck to do the job and make money .
None of use have any thing to lose based on your decisions . We are only trying to help you .
Take the help .

 

Finally, by Jove I think he's got it.

 

Wonder if this wrecker is running a direct 10 speed and 2.64 rears; one live axle and one dummy to save on fuel, with a APU to run the wrecker hydraulics, Prolly a Turbo3000D unit as well- man all that fuel money he’s gonna save will be out of this world!

 

Yep that guy he's pulling probably went with something stupid like an 18+4 and 4.30s. Gotta get dragged to the fuel stop now when he ran out going up the hill.

 

Kevin Rutherford specd that wrecker himself. It was featured on the cover of Green Peace Magazine. Al Gore was explaining how the AirCell intake spacers worked in conjunction with the turbo3000 and air tabs.

They are using straight tread tires all the way around it to reduce rolling resistance during high wind conditions.