looking to change my axle ratio

Impossible, just listen to the expert in here.

I dont have to drive a 2.64 ratio truck, to know what I have experienced. And if crossing into Poland, Russia, Ukraine, etc is that easy, why not go over there and tell them how to do it? Oh yeah, it takes common sense etc, never mind. There were FIVE of us from England that drove to the Eastern Block, thats it. There is a reason for that Mr Expert, it was far from easy, and beyond your comprehension when your compare it to crossing a state line.

Stop while you are behind, he knows everything, didnt you get the memo?

Oh just give up and buy some POS fleet truck that you can NET $150k a year with, all while pulling flatbed freight for a bottom feeding company.

It's funny though, all these companies that spec these fleet POS's the "right way" according to some, will happily PAY for those 23yrs of clean driving experience. Yep, no accidents, nada, and easy to verify by the prior mentioned bottom feeding fleets. Wonder why they pay MORE for my experience than for others......Maybe, just maybe, they at least know it's worth more than someone with computer knowledge.
And dont start about the "new breed" that you profess to be. Us old timers, as you call us, learn more in a day than 99% of rookitards learn in a month, and yet we still freely give advise out in the hope that it sinks in one in a thousand times, to make the roads safer and maintain the good living we have enjoyed over the years. Granted, we wont make the mega $150k NET that you predicted you will make this year after a couple of good weeks, but we try non the less.

Martin

 

Ok Richter I'll go with your theory on od vs non od. But all gears use power. Meaning what rear end ratio is more efficient? 2.64 or 3.55? You tell me. I'm not an expert. Some people in the hot rod world swear a Chevy 12 bolt is more efficient than a ford 9 inch due to position of pinion to the crown actual number of teeth and angles on the actual gears. Point is you could be gaining at the trans and losing at the rear end. Myself I think mega carriers went with direct 10 speeds because they were cheaper and they had to go to tall rear gears to have a reasonable road speed. But that's just me. Another thing is that 24.5 tires rotate less per mile than a 22.5 so are they really harder on fuel?

 

Nope, they went with 10 speed directs to dumb them down for the rookies that couldn't grasp a 13 or 18 speed. Same reason they went to auto's...

 

Rank if the truck needs tires just put good tall 24.5s on it. That was the spec back in the day and save money from changing gears. Run it and you'll get used to it revving. Work on the soundproofing. Those old engine only had a max of 1650 of torque and a lot were 1450 so they need to be in the middle of power to pull hills well.

 

I'll go with that reason also

 

Its gotta be something else. Peak HP may be at 1600 rpm,but the happy medium with torque is lower. Unless this is a mechanical engine.

 

You do have higher tourqe in trans at cruise speed running in direct, but as long as the trans is rated for it, its not a problem.

 

I've heard the biggest loss is when you change the speed the most. A 2.64 reduces a little and thus would loose less then a 3.55 that reduces a lot. This part is not confirmed by me, so it could be wrong. The difference is certainly less then what you save in the trans.

 

ok i'll throw my two cents in. the one with the 3.70 ratio gets better mpg. is because it doesn't have to use as much torque and hp to pull it's self up the hills like the one with 3.55s does at the same speed and weight. in other words doesn't have to work as hard. the so called torque band peak is hit sooner than the other truck. I went from 3.70s to 4.11s. guess what? mpg increased by 3/10s mpg regardless of overdrive or direct drive trans. but that is pulling some pretty good weight. plus if I was to run in direct drive gear my trans temp goes way up. which in my case isn't a good thing. now if you do as cowpie 1 does then I see the benefit to some extent. but I don't run out in the flat lands. there is no way EVER a taller ratio like your talking about will pull as well and maintain as well like a lower ratio like I run on a mountain pull period! with the same hp engines. it just isnt possible in real world. I may have misspoke at the beginning but I have had truck with 3.55s and 3.70s and 4.11s for pulling power i'll stick with the lower ratio gears. if you want to run 70mph or more in the flats then yes you will use less fuel than I will. at that speed my engine is screaming with 4.11s at 1700 rpm. in the hills i'll have a cold one waiting on ya when you catch up if it aint warm by the time ya get there.