Need to make a decision today to order my new gears. I've already discussed off line with Tom but I want to et a general concensus. Currently running 4.56 and 34.3s (4.20 effective) on my V10 Ex but feel it needs a little lower gearing with my 11K trailer. I wold minimally go with 4.88s which puts me at 4.50 effective over stock. Has anyone used 5.13 gears with this size tire or another combo that put them at 4.73 (or close to it) effective? If so, how did you like it when not towing and did you notice any difference in fuel mileage not towing? 80% of my driving is local with 45 mph max and half is in hilly area.
Thanks for any input

 

Can't remember if I mentioned it before, but I did run 32"s with the 4.88s for two years, effective 4.80 ratio. It was a hotrod around town but it did suffer some mileage loss, went from 14-ish mixed driving when all stock (3.73s) down to 12.5 MPG highway with that combo.

 

Opinions....
Probably a lot of fun running around town.
Expensive experiment, though.

 

The f450-550 chassis with gas motors and buses and motor homes use 5.30 gears from factory. Gvwr 25000

I have 4.30 gears and stock tires. I live in hilly country and would like more gear. I will not pay for it.

However when hen I bought my truck it had 245 tires on it and I liked the effective gear ratio better than 265. It had a more usable od on highway for me. I rarely tow over 65. That effective ratio was close to what you are considering.

I tow in 3rd on two lane hilly back roads at or under 55 and it would downshift less often to 2nd.

If if you want to drop the 2$k on gears for the improvement then I think you will like it.

Imho you have to change at least 2 steps in ratio for it to be worth it.

If you pull hills a lot then maybe worth it. If you live in Florida put the $ in your ROTH and push the OD off button once and a while.

If you want commuter mileage than take your foot out of it and leave for work 10 minutes earlier.

I drive like a grandpa but my stuff lasts a lot longer and I spend less in fuel.

 

How worn are your tires? Could you just go down a size or 2 when due for replacement?

 

I think I'll go with just the one step lower (4.88). With my tire size I should be close to WE3ZS effective ratio and he's pulling a heavier trailer than mine. As for the tires I don't want to go any smaller than the 34s I'm running now. Thanks for the input.

 

@65 mph your RPM will go from 2000 to 2300 with 34” tires.

 

I ran 5.13s on 32.6" tall tires and it was awesome! 70mph was about 2600 RPM and it pulled like a train. Gas mileage wasn't any worse but I had a lot more pedal left compared to stock 3.73s. I also ran 35s and 37s with teh same gears and for towing my big trailer, I liked it best with the small tires.

When not towing it was fine as well. I ran the 37s when not towing also, and it was nice but with the 32.6s or the 35s, it was great.

 

I changed from 3.73 to 4.56 on 32.8" tires (BFG KO2'S) for towing my 10k lb trailer. Very happy with it and never looked back. Works fine towing in the mountains in upstate PA and NY. Now, if I was to do a LOT of towing that trailer in those mountains, I would probably want a 4.88 or more.

 

When not towing it was fine as well. I ran the 37s when not towing also, and it was nice but with the 32.6s or the 35s, it was great.[/QUOTE]
Thanks Kai, I should be good for a mix of towing and every day with the 4.88s then

 

Thanks Kai, I should be good for a mix of towing and every day with the 4.88s then[/QUOTE]

Yeah with 34.8" tires it'll be fine. though I didn't like towing with the 35s as much as with my 32.6" tires, just a couple hundred RPM was noticeable. Still far better than stock though.