4.10 or 4.30 gears
 

Hello everyone. Been a while since I have been here. I know I need to be involved more and i would like to but at times time does not permit. Anyway I want to get a few opinions on gearing. I have a 04 F350 crew cab dually 4x4 with 4.10 gears. The truck has 46K miles on it and I have already done the head gaskets, head studs, egr bypass, coolant filter, free flowing 4" exhaust, no cat, muffler delete, pillar gauges. All work done with the advice of Matt at Spartan Diesel. Anyway the truck pulls 90% of the time. Mostly the truck is used mostly for our 40' toy hauler the tips the scales at around 17K. At 65MPH, is turning 2K rpm. I was wondering is going to 4.30 gears would allow me to pull the mountains here in the northeast a little easier and still be able to cruise at 70 mph easily. I just think the 4.30 gears will help it climb the mountains a little easier but wanted some opinions from some of you out there. by the way i am in Lisbon CT and my Shop / business is in North Franklin CT. Also, what is everyone's opinion about going with some aftermarket injectors????????

Go with the 4.30s!
 

If you can stand the extra fuel cost, I would definitely go with the 4.30s. It will definitely put less strain on your entire drive train and the truck will respond a lot better with your load. I turn 2K RPM @ 70 MPH with the 3.73 gears in my X so I assume you will turn about 2.3K RPM @ 65 MPH with the 4.30s. One of these days I will have to replace the X and my plan right now is a F-350 or 450 dually diesel with 4.30 gears. But the EPA my change those plans since I'm not planning to get rid of the X any time soon.

Sorry, can't help you on the injector question

DSMMH

I don't think it will make that much difference going from 4/10 to 4/30 you will spin the motor a little higher. I have the same set up as you and I wouldn't spend the money. So I vote stay with the 4/10.

Are you running stock tires or larger? If stock, 4.10 is plenty low and 4.30s will just hurt your mileage more, especially if you run 70 a lot. My dad's '03 is used specifically for towing and with stock tires and 3.73s we've grossed over 32k pulling over the mountain in eastern Oregon.

Charlie,

I have a 2005 F350 DRW with the Tow Boss (4.30 gears). I too tow a Raptor 36' Toyhauler loaded with 3 quads and a RZR in the garage. My last trip to Oregon I rolled on the scales. Trailer GCVW = 25100. Three passengers, full diesel, race fuel, on and on. No water on board, empty holding tanks. Trailer GVW was 16,200

My Truck is fully stock, stock tire size, no power mods, etc.

I bet your trailer at 40' (depending on make) weighs more than you think and fully loaded you are exceeding the GCVW for 4:10 and 4:30. All trailer mfg lie about weight. Have you rolled on to scales to check? (most don't because they are too scared). All my buddies run big trailers and we talk with so many the we know are way over the limit, pulling with 3:73 and above.

Look at FMC ratings for 2005 GCVW and they are different for 4.10 and 4.30. I have the detailed booklet at home. Everyone says it doen't pull any different and I won't argue. However, they are rated different and there is a reason. I believe 4:10 is 23,000 GCVW and 4:30 is 26,000. I will have to double check. Gear ratios transfer loads to the power plant. Easing that load up on the engine can makes a difference when climbing. On the flats, I think it is not a big deal. I pull alot of 6% grades going south and north. I'm in Northern CA. Grapevine, Siskoyous, Southern Oregon, etc.

Seriously, talking about gas mileage between 4:10 and 4:30 is like picking the pepper ouf the fly s**t. Anyone owning a diesel, pulling big trailers (thus the reason for the gear ratio) should not worry too much about mileage. Save the headache and buy reliablity and longevity.

I routinely run to the deserts in CA, NV and Idaho at 70 mph and if I recall turn about 2200-2300 RPM

If I could I would replace my 4.10's with 3.73's. I think the truck is plenty strong enough to spin them and I would like the better milage.

If you want 3.73s, I'll trade you my stock ones that came out of my truck. 75k on them and excellent condition. You can send me yours after the swap. Are they stock/Ford 4.10s or aftermarket?

They are stock. And I would jump all over this but I can not afford to have them installed nor can I do it myself.

Man, if you were closer I'd do the install for you cheap just to get the 4.10s.

Yea TX and OR are not too close.

Meet half way....:confused:
Cartmanea could do it at a rest stop... LOL

LOL, yea half way is like 1000 miles

Heh, no thanks. On a cold shop floor in December was bad enough the first time.

Make sure you reuse all the bearings too...:-X19
(inside joke)

Sure, why not, only 200k on 'em. :-banghead