[JackHammer]

I have been looking for transmission gear ratio specs on line at various manufactures websites. I am not having much luck so far.

What I am trying to do is find a transmission that will let me cruse along in my motor's happy place (1450-1500 rpm) at 55,60,65,70 and 75 mph.
the motor is an isx 475 hp. I have been thinking an 18 speed direct final type transmission would fit the bill for me.

I drive west to east coast and back pulling either 53 ft dry van or reefer so I see lots of variation in terain and legal speed limits.
I realise that nothing will prolly be a perfect fit. but I would like to come as close as possible.

[Kranky]

Go to www.roadranger.com then go to the road speed calculator and plug in the ratios to see what you'll need to get the desired result.

[JackHammer]

Thx muchly for the link to the calculator.
apreciate it.

[JackHammer]

Well acording to the calculator , running 22.5 LP's with a transmission ratio .73 & rears 3.25 I should see 76 mph at 1500 rpm.
I have also found the spec sheet's on all of eaton/fuller transmissions. so looking at all the various shift patterns it appears to me that an 18speed is overkill. A thirteen speed seems more like the way to go to me.
on truck paper I see a lot of Kenworth W900's with these specs.
Is anyone outhere running a truck with this setup ? how do you like it ?

[JackHammer]

I won't bump this again.

Any one useing a 13 speed transmission with a .73 final with the rear's being 3.25 ?

do you like this setup ? do you think something else would be better ?

[allan5oh]

With todays prices I don't think 3.25s are a good option because you basically always have to run fast with those gears.