Super duty rear ratio!

[muddyriver]

I'm starting to research buying a new truck. I'm defiantly going diesel this time and wondering what rear end a person should get. I'll be towing a camper around 9K. with about 1200K in the box of the truck. I'm hoping to buy used. My 6.2 had 3:73 which pulled our 8600# camper well, but wish it would have had the 4:10 in it. Does a person go to 3:55 or stay at 3:73 or even move up to 4:10. I would appreciate peoples information. Kind Regards, Nathan

[troubledwaters]

Seeing as you are buying used, don't let the rear axle ratio drive your decision. Whatever truck you find that blows your skirt up will work.

[pyoung47]

You should keep in mind that some SD are equipped with 17 inch tires. Witth 17 inch ttires, a 3.31 is equal to the 3.55 with 18 inchers

[muddyriver]

WOW, thank you all for the information and suggestions. I'm only looking a 2016 or newer. There's always the possibility to go bigger :). My 6.2 had the power but to drive something with everyday bad gas mileage really hurt. I tow a dump trailer from time to time so the diesel would help that out as well. the dump trailer is short distances. Glad that I don't have to narrow my search anymore than I have to. Helps keep the options open for the other things. Like A/C seats!!!!
thanks again for the help!!!

[spud1957]

theoldwizard1 wrote:
You have to look at the total ratio now with the new 6, 8 amd 10 speed transmission ! Super Duty implies Ford F250/350. I am pretty sure they both use the 6R140 transmission (used in Ford MH chassis and F650/750). The 3.73 will help with hills.

What is the ratio comes with the camper/HD trailer tow package? My gut says the 3.73 is a good choice.

As stated before, the camper package DOES NOT include an optional gear ratio. You can select the camper package with the 3:31 gear ratio.

[boshog]

muddyriver wrote:
I'm starting to research buying a new truck. I'm defiantly going diesel this time and wondering what rear end a person should get. I'll be towing a camper around 9K. with about 1200K in the box of the truck. I'm hoping to buy used. My 6.2 had 3:73 which pulled our 8600# camper well, but wish it would have had the 4:10 in it. Does a person go to 3:55 or stay at 3:73 or even move up to 4:10. I would appreciate peoples information. Kind Regards, Nathan

For reference, I'm pulling 15K of fifth wheel with 3:42s, no problems at all.

[Lynnmor]

theoldwizard1 wrote:
You have to look at the total ratio now with the new 6, 8 amd 10 speed transmission ! Super Duty implies Ford F250/350. I am pretty sure they both use the 6R140 transmission (used in Ford MH chassis and F650/750). The 3.73 will help with hills.

What is the ratio comes with the camper/HD trailer tow package? My gut says the 3.73 is a good choice.

The Ford F250/350 diesel will have 3.31 or 3.55 depending on tire size and a few options. To get lower gears, would require dual rear wheels.

[theoldwizard1]

You have to look at the total ratio now with the new 6, 8 amd 10 speed transmission ! Super Duty implies Ford F250/350. I am pretty sure they both use the 6R140 transmission (used in Ford MH chassis and F650/750). The 3.73 will help with hills.

What is the ratio comes with the camper/HD trailer tow package? My gut says the 3.73 is a good choice.

[Lynnmor]

It's interesting that folks talk about rear end gear ratios over and over and compare with those they had in the past, but never consider that modern transmissions have several overdrive gears. For example, Ford six speed transmissions behind a diesel engine have fifth gear as an overdrive and sixth gear is over that overdrive. If you want to compare, multiply the sixth gear number times the final drive number. You will then find very high gearing that works fine with a slow turning diesel engine.

[spud1957]

nohurry wrote:
Just to add to what’s been said; the 2015 F350 I had came with the camper pkg, which included 3:55 ratio on 18” wheels. But many are pulling bigger trailers than yours with 3:31’s just fine. If you find a truck that’s otherwise equipped as you want, I wouldn’t let it stop you. Good luck in your search.

Maybe just to clarify your post. The camper package on the F350 includes a front spring upgrade and a rear stabilizer.

The 3:55 gears are not part of the Camper package. They are a seperate N/C option.

[valhalla360]

You said "used". How old?

Back in the days of 3 speed transmissions a numerically higher rear end could really help towing.

When you start talking the newer 8-10 speed transmissions, the rear end drops off as a major consideration unless you are pushing the truck to the maximum. The transmission can compensate by picking a better gear to get an overall gear ratio it desires.

[nohurry]

Just to add to what’s been said; the 2015 F350 I had came with the camper pkg, which included 3:55 ratio on 18” wheels. But many are pulling bigger trailers than yours with 3:31’s just fine. If you find a truck that’s otherwise equipped as you want, I wouldn’t let it stop you. Good luck in your search.

[danrclem]

Is there a possibility that you will buy a bigger camper in the future?

[4x4ord]

As has been said 3.55 is your only option with 20" wheels. With 18" wheels either 3.31 or 3.55 is available. I have 3.55 gears with 20" wheels and the truck pulls my 16000 lb RV eaaily. I would recomend 3.31 if your happy with 18 inch wheels.

[rjstractor]

Even with 3.31 rear axle gears that truck will tow the snot out of a 9K trailer, or one twice as heavy for that matter. The diesel has over twice the torque of the 6.2 gas. Comparing with a 3.73 equipped GM truck is not valid comparison since the Ford has lower transmission gearing. A 3.31 equipped Ford has more aggressive overall gearing than a 3.73 equipped GM.