At that point I'd just get an F350. I dont know what the difference is between the F250's and F350's cost wise is on the 2020's but when I was looking a year ago the difference was ~$1500. The extra payload on an F350 is nice. I do understand there are some registration/insurance considerations depending on state.

 

Why would you let $200 in front coil springs determine which gear ratio you live with? Takes all of 2 hrs tops to change the coils.

 

Mptjelgin - Seems reasonable. Thanks for your reply!

 

At my age I didn't want to deal with changing the coils.

It would be a $500 deal for me. $100 for the HD option, $200 for new springs and another $200 or so for labor.

The RPM at cruise with 3.31's and 18" wheels is pretty close to 3.55's and 20" wheels.

 

Can anyone comment on what comes with the High Capacity Trailer Tow package when selecting the 3.55 gears? I understand there are upgraded gears, but what about leaf springs? Hoping this doesn’t make the ride firmer in the rear.

 

So, my dealer ordered two KR trucks with similar specs, one with 3.31 and one with 3.55 rears and I have the pick. Both are at the dealership and picking up next week. Is there really any difference in ride unloaded with the HCTT package? Again, no real towing, mostly used as a DD.....

 

I am new to the diesel world and the gear options. I was looking for a 2017 F350 and did not pay attention to the gears. I friend told me with diesel, the truck will start to go when you let off the brake pedal even with a trailer connected. I test drove a couple and I could feel the truck wanting to go like my friend talked about. I did settle on a 2017 F350 but it does not have that same feeling. I looked and I have the 3.55 gears. Is that why? Will the 3.31 give you that power when you let off the brake? The 3.55 pulls my 10,000 travel trailer with no issues. It stays in 6th gear almost all the time. I could not be happier. I have the standard 20" rims and tires. I just want to know is that what I am feeling or is something else.

 

No just the opposite 3.55 will give you better torque everywhere. In theory if you let off the brake with 3.55 vs 3.31 your truck will have an easier time (engine and transmission) moving. The higher the gearing number the more of a mechanical advantage you have. The down side of higher gearing is that you are turning higher RPM's. Your top speed with be less and your MPG will be less if traveling at the same speed as you were with 3.31's. If you were to go up a tire size, say from 33's to 35's then 3.55 gearing would get back to the stock pulling power (RPM's and MPG's) of 3.31 with 33's. These trucks put out a **** ton of torque (2017 is 925 lbs). If your truck feels down on power it's not because of your axle gearing.

 

It may be that you are feeling the Hill Start Assist where the trucks breaks automatically remain applied until you apply some throttle. As noted below, 3:55s have more mechanical advantage than 3:31s so they allow the truck to move the same load easier.

 

If you tow extremely heavy, plan on putting bigger tires or do a lot of city driving get the 3:55. If you drive lots of highway miles and don’t tow super heavy go 3:31. I’m trying to sell my 19 Ram so I can get a 20 F350 and I will definitely go 3:55.