3.73 are not available on the pickup version of the 6.7 350. It's a CC option only.

As to what you need, you can't go by what others need or what they tell you that you need. Either truck will be fine for the RV in question. It's what you want and what makes you comfortable. There are guys out there that want a 450 for anything bigger than a popup. There are guys out there like me that are perfectly happy towing a large 5ver with a SRW. There are guys at all levels in between. It's not a right or wrong situation but rather personal preference.

 

I pull a 15K 5'r with a F350 dually CC and would not go smaller. I think you would be much happier in the long run with the F450, getting used to the duals doesn't take long, my wife loves mine. The added stability and safety with duals far outweighs any inconvenience that they create. You learn to ALWAYS back into a parking spot, you may have to park farther away from the store and they don't fit through many drive through car washes, but even my wife wouldn't trade ours for anything. On long trips by the end of the day I don't feel as worn out as I would when driving a SRW, they just track better and are bothered much less by crosswinds and big trucks passing. I have over 5 million miles over the road in big rigs and have lost count of the number of RV's wadded up of the road because they blew a rear tire, I can remember only 1 dually that lost it and he may have hit something and blown both rears, not a common problem.

 

That trailer has a 2655# pin dry without options. Things like a 2nd ac, battery, propane, etc will make your pin around 2900 - 3000 before loading and 3300 - 3500 loaded. If you want a nicely equipped truck, 4x4 crew with a 6.7, your payload will be in the 3200 - 3400 range. With passengers and a 150# hitch, you'll be over the payload rating of a SRW.

if you go DRW, the tight turning of the F450 is VERY valuable, especially parking and backing a trailer.

 

Ours is a late 99 F350 7.3L CC LB SRW, we just took it on a 5k mile trip with our 4 kids towing our 9200# 5th

I only wanted a DRW for 300 miles, the crosswinds were insane in Kansas, 40-45mph, semis trailers were slanted to the point you could see the cab while following behind them, as their trailer was pushed 2 feet to the right.

A short turning 450 would have been really nice in some campgrounds with our truck's ridiculous 59.5 foot turn radius.

But when we were unhooked and driving around to see the sights the 19.5mpg was nice

 

I have a 350 SRW with 20" wheels and 3.55 gears - a pretty tall combination. It has pulled well over 15k through some big hills. Does it do it? Yeah. If I was pulling like that routinely, though, I would not recommend that set up. Pretty much 10k is the zone with my truck. That and over the truck starts off slow. Lower gears would alleviate that. Once rolling its fine, and in the hills its fine. If I get in to the hills it will down shift. I have not had any scenarios where I didn't feel like I had enough power on the road, just the slow take offs.

You did not state the weights you are dealing with, just loaded and the RV model. Have you scaled the RV loaded? What is your pin weight and gross weight on the RV? That will be important to know as picking a truck would heavily rely on that.

If you are in the 12-15k range you can get by with an SRW. I would get lower gears and 18" wheels, though. The wheel size affects the final drive gearing - smaller wheel = smaller tire = more torque to the ground. 3.73 gears and 18" wheels would probably give me the right comfort zone with the 15k load range for more routine pulling. Since they aren't offered you could get 3.55's to start and then re-gear to 3.73 (this would be a matter of swapping the ring and pinion gears in your front/rear differentials - assuming it is a 4x4 truck - then re-programming the computer to the new axle ratio so your odo and speedo line up right - same thing for tire size changes).

If you are in the hills a LOT 4.10 gears might be better, but you will lose fuel economy when not pulling with the higher engine RPM.

If you are closer to 20k gross on the RV and hills you may want to go to the 4.30 gears.

Watch your rear axle ratings and rear tire capacities - especially with an SRW truck. This will be a quick limiting factor. If your pair of tires combined has a lower rating than the what the axle is spec'd for then use that. Scale the truck and make sure you are UNDER the lower of the two ratings when loaded (tires combined or axle).

Again, figure up real weights that you are dealing with. Once you know those then you can get to the truck selection. If you are max'ing out the pin weight on an SRW truck skip it and go to a dually off the bat. What gears you get isn't the end of the world. If you start with too tall of gears (3.55's lets say) and you aren't happy with the way it pulls you can change them later without trading the truck in. I wouldn't sweat it one bit. Just let the weight guide your SRW/DRW decision. I would be more comfortable with a DRW, but for what I have pulled with my truck I am more than happy with the set up.

 

if your looking at new 2017-2018-2019 its an entirely different ball game from the earlier trucks.

The spec on the North Point 315 RLTS is 15250 GVWR - so your looking at ~3100lbs of pin weight fully loaded- a lightly optioned SRW will have no problem with that.

We pull a 16,000lb 5th wheel with a SRW and 3.31's (note: 18" wheels) and I am very rarely in need of additional power. We typically run at 75mph (on cruise control) with no dramas in 6th gear. No sway, no "white knuckling", certainly no desire or need for a DRW truck. I would recommend a long bed for the fuel capacity, though we certainly have made it work with the puny 34 gallon in the SWB. I was skeptical at first of the 3.31's as well coming from 3.73's, but its a non issue.

They don't come with 3.73's anymore, and there isn't a need. This isn't a 7.3 or 6.0, the torque on the new spec 6.7L is ridiculous.

 

I always think it isn't just about pulling, it also is about breaking it safely in an emergency situation oder having to take a turn harsher than usual. That's when looking at a dually or F450 comes into play.

A human can pull a truck once it's rolling, but can he stop it?

 

I pulled a 371 Fuzion using son in law's F250 SWB....night and day difference moving up to my present '17 F350 DRW long bed. No more worries about exceeding payload weight and safety concerns when my family is riding in the cab. The 48 gallon fuel tank on the 176" WB trucks is nice too! Never had any problems making tight turn's with this truck and trailer combo compared to years ago when I drove a W900A model KW latched onto a 9,200 gallon tanker!!



My present old retired guy's rig!!

 

If you are planning on running in the mountains it would be a good idea to think about a dually and lower gears for many reasons. also the bigger brakes is a big help. Like has been said before the F450 has the best turning radius, heavy tires and LARGE brakes plus the lower gears. (uses a little more fuel unloaded) Transited from gmc 3500 3.73 gears. Slow to start but great puller, not enough capacity or brakes. Do what fits for you and have fun.

 

X2^^. You will be at or near 3,507 lbs. loaded pin weight on that fiver. Do you really want to put that on a SRW truck and pull it down the road at highway speeds? Youll need at least an F350 DRW.

Rob

 

The trailer brakes stop the trailer, not the truck brakes.

 

Once rolling at 65 mph try activating the trailer brakes using the hand switch (don't touch the trucks brakes); in an emergency (my opinion) there's not enough effective braking back there.

 

I have. Mine will darn near lock up and pull the truck backward if you pull the slide all the way over when not adjusted down. If your brakes can't pull the truck to a stop, they aren't adjusted correctly or need replaced/serviced.

 

In an emergency locked trailer brakes are not ideal; my opinion is trailer brakes only assist.
I prefer a tow vehicle that's capable of handing the load.