Estimating a good weight range for a (not yet purchased) truck and 5-er

[go6car]

I've been doing a bunch of online reading on fifth wheels, but I'm still not sure of a few things...

Looking at a (maybe) future purchase of a 2012 Ford F350, SW crew cab (3.55 gears - no choice apparently on that now), with a max tow rating of 15,200 - 15,700. (I understand a dually will give me significantly more at ~21,500).

Since I don't have an actual truck for actual weights, how can I best estimate a good, safe weight "zone" for what type of fifth wheel I can safely pull with this truck? I only have the online posted 5-er weights and pin weights to go on that are on the manufacturers websites (also understand that actual delivered units tend to be heavier).

So, for example, I'm looking for just a safe, general ballpark range to start looking in for this particular truck (something like around "x" lbs, with no more than an "x" pin weight).

I know weight can be a sensitive issue on the forums, but again, I'm just looking for an approximate estimate so I can either include, or rule out, some of the new 5-er manufacturers and rigs I'm looking at online.

Thanks for helping to educate me!

[BCooke]

People who like to play it safe, will run at a max of approximate 80% of max. Others will tell you you can pull what they rate at.
Personally I had a v-10 f350 srw and after pulling 13k, in PA,(rated at 14k) I moved up to a diesel dually and am much happier with the towing; not the payment

[RustyJC]

First of all, manufacturer's trailer tow ratings (MTTRs) are just "marketing fluff" numbers. Here are two reasons why:

1. The MTTRs are calculated as the truck's GCWR minus the truck's curb weight. The problem is that the manufacturer uses the curb weight of a base model truck with no options or accessories (like, for instance a 5th wheel hitch) and with only a 150 lb driver. In other words, the curb weight is artificially (and substantially) lower than the curb weight of a real world truck loaded with driver, passengers, options, accessories, cargo, full fuel tanks, hitch, etc. which greatly inflates the MTTR. The actual towing capacity of the truck without exceeding its GCWR is:

Truck's GCWR - truck's true laden curb weight (LCW) = maximum total weight of loaded trailer

2. The MTTR totally ignores the truck's GVWR and GAWRs - UNTIL you get into the fine print where you'll find a statement to the effect that "none of the truck's other ratings are to be exceeded when towing." With a SRW truck towing a 5th wheel, one will almost invariably exceed the truck's GVWR long before approaching the MTTR. To avoid this, the following formula should be factored in the sizing calculation:

Truck's GVWR - truck's true laden curb weight (LCW) = maximum pin/hitch weight of loaded trailer

When shopping for trailers, I would recommend that in the above calculations one should use the trailer's GVWR as the maximum total weight of the loaded trailer and 20% (5th wheel) or 12% (TT) of the trailer's GVWR as the pin/hitch weight of the loaded trailer. The published dry weights of a trailer are as unrealistic as the truck's MTTRs - unless one plans to pull an empty trailer with no options or accessories or propane or batteries or cargo or ......


Rusty

[JC2]

Quote:

Originally Posted by go6car I've been doing a bunch of online reading on fifth wheels, but I'm still not sure of a few things... Looking at a (maybe) future purchase of a 2012 Ford F350, SW crew cab (3.55 gears - no choice apparently on that now), with a max tow rating of 15,200 - 15,700. (I understand a dually will give me significantly more at ~21,500). Since I don't have an actual truck for actual weights, how can I best estimate a good, safe weight "zone" for what type of fifth wheel I can safely pull with this truck? I only have the online posted 5-er weights and pin weights to go on that are on the manufacturers websites (also understand that actual delivered units tend to be heavier). So, for example, I'm looking for just a safe, general ballpark range to start looking in for this particular truck (something like around "x" lbs, with no more than an "x" pin weight). I know weight can be a sensitive issue on the forums, but again, I'm just looking for an approximate estimate so I can either include, or rule out, some of the new 5-er manufacturers and rigs I'm looking at online. Thanks for helping to educate me!

The part that concerns me is the 3.55 gear ratio as 3.73 or 4.10 is the way to go. I'm afraid the 3.55 will show up as lack of power when towing along with frequent trans shifting. I also agree with the dually recommedation.

[Billieg]

Quote:

Originally Posted by RustyJC First of all, manufacturer's trailer tow ratings (MTTRs) are just "marketing fluff" numbers. Here are two reasons why: 1. The MTTRs are calculated as the truck's GCWR minus the truck's curb weight. The problem is that the manufacturer uses the curb weight of a base model truck with no options or accessories (like, for instance a 5th wheel hitch) and with only a 150 lb driver. In other words, the curb weight is artificially (and substantially) lower than the curb weight of a real world truck loaded with driver, passengers, options, accessories, cargo, full fuel tanks, hitch, etc. which greatly inflates the MTTR. The actual towing capacity of the truck without exceeding its GCWR is: Truck's GCWR - truck's true laden curb weight (LCW) = maximum total weight of loaded trailer 2. The MTTR totally ignores the truck's GVWR and GAWRs - UNTIL you get into the fine print where you'll find a statement to the effect that "none of the truck's other ratings are to be exceeded when towing." With a SRW truck towing a 5th wheel, one will almost invariably exceed the truck's GVWR long before approaching the MTTR. To avoid this, the following formula should be factored in the sizing calculation: Truck's GVWR - truck's true laden curb weight (LCW) = maximum pin/hitch weight of loaded trailer When shopping for trailers, I would recommend that in the above calculations one should use the trailer's GVWR as the maximum total weight of the loaded trailer and 20% (5th wheel) or 12% (TT) of the trailer's GVWR as the pin/hitch weight of the loaded trailer. The published dry weights of a trailer are as unrealistic as the truck's MTTRs - unless one plans to pull an empty trailer with no options or accessories or propane or batteries or cargo or ...... Rusty

X2
If you want to be safe then a 5th of around 12,000 -13,000 fully loaded would be your max. I also agree the dually would be much better and you wouldn't have to worry so much about the trailer.... My F350 diesel/dually, 410 gears has a hard time pulling my 13,700# 5th up steep grades. I'd hate to think about 355 gears....

[BCooke]

With the 6.7 there will not be a problem towing 14k. I am able to out accelerate some of the eco friendly vehicles.... of course I am not getting the mpgs they are. you know if you figure out gpp (gallons per pound) I might have them....

[Billieg]

Quote:

Originally Posted by BCooke With the 6.7 there will not be a problem towing 14k. I am able to out accelerate some of the eco friendly vehicles.... of course I am not getting the mpgs they are. you know if you figure out gpp (gallons per pound) I might have them....

Ya but the OP said he couldn't afford the newer trucks.

[go6car]

Oh, it would be a new 2012 350 (just single wheel). Not sure why Ford isn't offering a gear option there.

Thanks for all the feedback!

Looks like I would be looking in that 12000/13000-ish range fully loaded based on what everyone is saying, which puts me around 10,500-ish dry weight. Wow, I was hoping for a bit more, but seems like the only way to get that is a dually.

I had my online eye on something like that new Thor Redwood 31SL (actually 34 feet), but looks like it would be too heavy (assuming "shipping weight" would be "dry":

Shipping Weight:11,930

Carrying Capacity:4,070

Hitch Weight:2,160

Axle Weight:9,770

[RustyJC]

Quote:

Originally Posted by go6car Shipping Weight:11,930 Carrying Capacity:4,070 Hitch Weight:2,160 Axle Weight:9,770

Just to show how "published data" can get one in trouble.

The apparent GVWR of this 5th wheel is 16,000 lbs (11,930 + 4,070). As such, the loaded pin weight could approximate 3,200 lbs (20% x 16,000). That's what the truck's GVWR should be sized for. If one looks at the published pin weight of 2,160 lbs, the loaded pin weight applied to the truck could be as much as 1,040 lbs (3,200 - 2,160) greater than that shown in the brochure.

Rusty

[go6car]

Agreed! Confusing as heck to the laymen, espeically when I don't have the actual truck to factor in yet!

The thing is, though, I'd never come close to 4k capacity (I think this particular unit is marketed as a full time rig). I'd be more like 2k capacity, max. We're weekenders and primarily stay local, with maybe one longer trip per year (4+ hours away from home).

So, following the math, that would put me at ~14,000 GVWR; with pin approximately at 2800. If that new 350 is rated at ~15,200 - 15,700 (depending on how equipt), wouldn't that put me theoretically " in the zone" for this truck; albeit at the upper end?

Not saying I'm ready to pull the trigger, per say - just more wanting to ensure I'm understanding all this correctly! (And, thanks for your patience!!)

[RustyJC]

Quote:

Originally Posted by go6car If that new 350 is rated at ~15,200 - 15,700 (depending on how equipt), wouldn't that put me theoretically " in the zone" for this truck; albeit at the upper end?

That 15,200 to 15,700 (manufacturer's trailer tow rating) doesn't include your true driver weight (150 lbs is assumed by the manufacturer), passengers, cargo, accessories (how much does your 5th wheel hitch weigh?), etc. Every pound you add has to come off of the trailer tow rating.

Also, you'd need to double-check the allowable hitch/pin weight (truck's GVWR - truck's laden curb weight) to ensure that you didn't exceed your GVWR.

There are a number of spreadsheets linked HERE that can walk you through this process.

Isn't shopping for an RV and tow vehicle fun???


Rusty

[JIMNLIN]

Your selling the '12 F350 SRW short on its 15700 towing capabilities. IMO some folks are still stuck with towing performance we had with trucks of the '80s/'90s era which using the 80 percent thing made sense. Not so with todays trucks which work fine at their max rated capacities.
Yeah I know someone had a max loaded truck and didn't like it but for every one of those we can find many more that are comfortable towing the same combo with no issues.

The F350 has three wheel and tire packages. The highest capacity is the 20" wheels and tires that carry a 7000 RAWR with up to 11500 GVWR. Payloads range from 3900 up to 4460 lbs all depending on cab/wheel and tire configurations. Study Fords http://https://www.fleet.ford.com/tr...Pickups_SB.pdf
for configuring your F350 SRW with the most payload capability.
When figuring weights its all a guessing game till the truck and trailer go on the scales. Probably the biggest some folks use the trucks GVWR for figuring axle/tire loads. Thats where the newer websites from each truck manufacture can be used to get a very close estimate on actual weights. Your buying the truck so use its capacities and capabilities.

[TXiceman]

The 3.55 gears are still a problem. They are planning to take all of the torque amplification in the tranny and make yo drop to lower gears. From an engineers view point, I would want a 4.10 axle and let it take care of the torque. Much wasier on the tranny this way.

Ken

[go6car]

I so very much appreciate all the different feedback - thank you!

I know about towing on the upper ends (we do that now) with a TT, but it's a whole new experience trying to learn about a fifth wheel with an imaginary future truck to boot! I think you're absolutely right about the configs and getting the max there. Until then, I'm trying to hypothesize, which is tough! And, a bit all over the place since I'm trying to generalize and narrow down a few manufacturers in order to even begin to take a closer look. Some of the higher quality manufacturers are out because there's no way I'd be comfortable pulling them without a dually. We'd really like to stay with a SRW for a number of non-camping related reasons.

The gear issue is interesting and I definitely need to research that more too.

When we first got our current F150, you'd be amazed how many people were "shocked" that we were pulling the trailer "with such a small truck". (We've been to the scales, and yes we are within all ratings). The truck handles our current set up like a champ! But, we become limited if we want to increase payload (add a bunch of people in the cab and their stuff in the bed), AND fill up our fresh water tank. It's all about knowing what you can and can't do, safely (which also seems to generate a lot of heated discussion! ).

I was looking at Class As, but my better half would like a truck anyway, so that has led me to taking a better look at 5-ers to see if they would work for us. I haven't really found any TTs that meet all of what I'd like. The things on the short list are:

• NO MORE GOSH DARN DECALS! (Full body paint, or colored gel coat if I have to)
• On board generator
• Self-leveling jacks
• Room to sleep two other big guys (independently from each other) and from us
• Needs to fit in the driveway between trips so we can take our time loading/unloading (no more than ~36'-ish).
• Towable with a SRW truck.

I'm sure there's more, but those are the important things for now!

I'm still reading as much as I can too, so if there's any more two cents on any of this, please by all means keep it coming!