Gear ratios power vs. economy

I'm confused, are you looking to change gears in your truck, or are you buying a different truck?

 

If you are going to buy a truck this is what I recommend ,,A 10 speed is OK if you don't driver mountains and haul mostly on the interstates with legal weight loads,

Buy at least 500hp with 1850 torque,,HP is for speed and torque for pulling power..Get a 13spd but and 18 is much better,,a rear ratio around 3.36 to 3.25 with 22.5 tires,,

And don't buy a small engine and reprogram the ECM for more HP<,Most likely the trans is not rated for more HP or torque,,Poor mans way to HP usually means more drive train faliure

I used to haul 110,000lbs gross with 3.36 rears, 18spd and 500 HP on 24.5 tires,,many times I never got past 16th gear..
Last truck hauled up to 150,000lbs,,3.73 rears,18 spd with 600 HP.

more gears are better (just because you have all those gears you don't have to use them all the time) and when you buy a truck you got to think of the future,what you haul today most likely will not be what you haul a year or more in the future,,Resale is an other factor too,,old trucks wih 10spds are very cheap 18spds sell better,
An other factor for more gears is for over 20 years the big companies especially private carriers have been pushing to raise the max gross legal weight to 97,000lbs to match Canada and Mexico,,3 axle tractors and 3 axle trailer,,with a 10spd you will suck trying to oull 97,000lbs and in the mountains forget it,

Got to think about your future freight and buying correctly spec'd equipment makes a big difference,,
No matter what kind of truck you buy and what you paid for it you don't know how much the truck really cost until you sell it,,next month,,next year or 10 years down the road

 

What about my 04 t600, 3.70, 285/75r24.5, 10 sp, stock mbn but tuned up to 500 hp, no idea how much lb ft I got because the previous owner never told me about torque, 1650 lb ft on my tranny. One thing I know about eaton tranny specs. You can rate at least 100 ft lbs. According to my eaton 10sp brochure.

 

Confushious say go big , agree 500hp cummins or cat and at least 13 SPD, the split is so much more efficient on hills/ mountains. Just my .02

 

a shop can plug the computer into your truck and tell the torque,,get the trans model number off the tag and then go to eatons web site to look up the trns spec's,,,shop use in Utah has told me for years they see a lot of used fleet truck that were turned and but were having trans failures,,
even the u-joints have torque ratings as well as the clutch,,, a little more HP and fire blowing out the stack can end up costing money,,get the spec's off the components and check them out,

 

This has literally been the biggest battle while I've been looking at trucks. I don't want any more than a 3:55 with a 13. Most rigs I've been seeing are 3:55-3:73. I feel like if I get a 3:36 or near that my mileage would be a ton better. Given I'm specing for flat/step. Any useful info would help.

 

It will cost you $3,000 or more to change rears,,,3.55 with 24.5 if you have 22.5 tires then 3.42 or smaller..a 13spd will do you good if 110.000# will be your target max.
No if you get an RGN that is not hydrolic you will need to have a good set of end frame ramps for the roller on your gooseneck to roll on when you back under the trailer,,a lot of guys will go cheap on the ramps but the end up breaking up,, my 2 tractors it cost me about $2500 to have them made,,one big advantage with hydrolics is on ice or snow it is is very easy to back under and hook to the trailer.
I was in ND once and the ground was covered with ice and snow and I could not even unhook,,The trailer brakes were locked but the trailer just slid on the slippery ground,,had to go a couple miles away to a yard that had the ground cleared to bare earth to unhook and detach,,
Take your time to find the right truck,,if not you could screw yourself,,
Check Paccar Finance,,GE Capital,,Stay away for Arrow truck sales they got a lot of crap,,also check landstar web page, www.lcapp.com ,a lot of O/O with landstar trying to sell out,,