10 to 13 or 18?

I think you've been drinking tonight.

 

^^^^^^^^

 

you could run an 18+4 if you wanted to. what is your inal gear in the tranny? if its .75 dont matter how mnay gears ae in front ofit

 

The 10spd you have now - is it a 10spd OD or 10spd direct?

 

Some folks think the 18 thing means a taller final gear. Think of it as a 9 speed with a splitter

 

13 would make splitting gears going up the hills easier,.. but thats about it.

I have a 10 spd in mine as well and I loath the 10 spd. Much rather have 13 or 18,.. just to be able to get the right RPM for hills easier.

1600 RPM would be a lot for something like a big Cummins or CAT. But for a smaller Detroit,.. 1600 probably wouldnt be too bad.

I have 3.55 and 10 spd on 22.5 LPs in mine,.. I've learned to just slow down. 63 - 65 is all I push it. I'll run it up to 70 - 72 before a long hill to get some momentum to carry me up it. But cruise control is normally set at 62 - 63. Other guys fly past me all the time. What I have learned is that your not really gaining that much time running 70,.. even coming from 63 - 65 mph. In a perfect world,.. dropping to 65 from 70 over a 10 hr period,.. provided you never stop for pee pee or num nums,.. you'd lose what,.. 50 mile? From my own logging,.. for me its more like 25 - 30 mile difference when you take the hills, terrain and traffic into consideration.

I've considered switching to 24.5 wheels with 11R tires. Besides dropping my RPM's for fuel economy reasons,.. not sure if that would be a good combination with a 10 spd for climbing hills.

Hurst:smt111

 

IDK about you, but I shifted like 8 billion times in my career, and the less I shift the better( I'll be in the cold, cold ground before I drive a truck with an automatic) Years ago, the 13 speed was designed for those worthless 2 cycle Detroit's, where a drop of a hundred RPM's meant grab another gear to keep the "needle against the pin". I've had great luck with 10 speeds, and most of my company jobs, the trucks had 10 speeds and were very dependable ( had trouble on occasion with the splitter not working on some 13's) and with today's high horse motors, splitting gears is really not necessary. If it's top speed your after, you could go to big rubber, but have fun trying to find those. Besides, 70@ 1600 is just fine nowadays.

 

I am not a gear man but worked with some of the very best, a 10 speed is great for flatlanders, a 13 is great for highway, under 90,000 lbs, and an 18 speed is for heavey haulers, and off road.

 

I have Eaton Fuller 13 manual original with 1,418,000 miles, since I bought the truck new the only maintenance expenses I had was 3-4 oil changes; solid built ,reliable and offers options to play fuel efficient even with heavy loads in different road conditions/ speeds.