New Truck - Is My Math Right?

[sliptap]

Hi Everyone,

My wife and I recently purchased a truck for towing. I've been running the numbers to see which RV's we could purchase and would appreciate you spot checking my math.

Here are some base specs for my truck:

• 6600 GVRW
• 1330 Payload
• 8000 Towing Capacity
• GCVWR 13300
• 5270 Truck Curb Weight

It's a 2018 F150 2.7 Ecoboost. I believe payload is my biggest limiter here.

Let's assume 620 lbs of guests (wife/fake kids/dog) and 125 lbs of additional cargo (WDH and 50 lbs gear).

Where I am stuck is calculating the hitch weight. I've read that I should assume 14% of a trailer's GVWR should align with the hitch weight. So if I assume a 4000lb GVWR trailer, then I would just barely be under my payload limits. That would be 560 lb hitch weight (4000*14%). This would assume I am diligent in what goes in the truck as well as not overloading the payload of the trailer.

The math = 1330 - 620 - 125 - 560 = 25lbs.

Am I correct with the hitch assumption? Am I missing anything else? For reference, we've been looking at Coleman Lantern 17B as a potential trailer and I believe that has roughly 3800 GVWR. I think our saving grace could be filling the truck with water at the camp site.

Thank you for any advice!

[Jebby14]

You are on the right track, you decide how close you want to go. I'd be looking for a truck that was better equipped but you are in your numbers. For what its worth my f150 is rated for 1950 payload. i upgraded from a grand cherokee with 1250 lbs payload. best change ive made. by the way good job on your homework. most dont do it as well as you.

also assuming 14% of campers gvcr is a great way to start not the silly made up tongue weight they offer.

[Slowmover]

Payload and tongue weight don’t equate.

A WD hitch will leave about 68-75% of the TW on the tow vehicle..

An 1,100-lb TW is going to have about 400# effect on each TV axle. That’s car, SUV or van territory.

Payload has a different effect. Load it up and scale it. See for yourself.

The stiffer the spring package, the worse it will be unless the cab & bed are sufficiently loaded ON EVERY TRIP.

An “ideal” to work towards is where the tow vehicle is roughly 50/50 in weight division before hitching. Afterwards, 10% more on the rear axle.

The old rule was of one-thirds in how to set a WD hitch. 1/3 of the TW to each point (2 on RV, one on TT).

Stiffer the TV suspension, the less stiff need be the WD bars. TW IS NOT the determinant.

But it still comes down to how heavily the TV is loaded prior to hitching.

Pickups are already nose-heavy. Unstable. Towing only makes that worse.
Get the bed load on or ahead of the drive axle. Secured tightly.

The trailer needs to be level after WD is set. TV slightly tail down US NOT a concern.

Scale readings are ALWAYS max fuel, full propane & full fresh water. That baseline is easily replicated.

Is there about 400# or more remaining capacity for each axle when loaded for camping, all passengers aboard and unhitched?

Much more than that IS NOT beneficial. Is detrimental.

I run mine right at RAWR. My pickup carries 1200-lbs constantly. The 35’ trailer is such that getting the Steer Axle back close to solo value is possible. 2WD with IFS makes that easier.

“Weight” isn’t the problem. It’s in having steering, braking and handling relatively unaffected after hitching.

1). Steering IS different, granted. But that’s more to do with TV loading.

2). Does it stop faster once hitched? If it doesn’t, failure lays in the above (given correct brake action).
a). Empty pickup bed (weight ratio) and nose-down trailer means braking is 50% and less of what it should be. I hope it’s obvious WHY.

3). Tire pressure is ACCORDING TO LOAD. Not over or under book value, as either WORSENS all aspects of performance. Better shocks, etc, is the help to consider. Trailer leaf springs should be dumped for torsion axles.
a). TT tires always to max value.

Driver bad habits solo are also a concern. Braking into corners. Failure to slow sooner. Failure to stay below traffic flow. Failure to maintain adequate separation distance. Start now. Towing is not the time to begin.

Given what I see on the highways, the above are nowadays UNIVERSAL failures. Kick the teenager out of the drivers seat.

.

[Grit_dog]

It’s a wonder some of you who are responding actually have a RV and camp!
The way you make it sound, it appears that your opinion of owning and using a TT is more complicated than a bio-physics thesis and the operation of it is like trying to keep a neglected jalopy on the road.
It’s not rocket science and it’s not the maintenance nightmare some make it out to be.

Although the less mechanically inclined and the less prone a person is to general maint and upkeep, the more of a “hassle” it appears to be.

[TomG2]

Huntindog wrote:

Most affordable quality units are heaver than their competition. Heavy axles, frames and other componenets add weight. There really is no way around it without breaking the bank.

A lightweight unit that doesn't hold up can be far more expensive than a heavy unit towed with a stout truck.

One way or another, you will pay.

Equating more weight with more quality is a bogus assumption. Cheap shoddy heavy parts and components are available to the builders. In fact, some great engineering examples of lighter and better are out there. Casitas and Airstreams come to mind. Anyone can build heavy, no trick to that.

[Huntindog]

“Be sure to get the lightest trailer that fits you and equip things with a good hitch and you should be ok.“

This statement should come with the following caveat: Low weight generally means a less durable unit.
Thought it is possible for a builder to use expensive materials to make a unit hold up, few will pay the price that would be required.

Most affordable quality units are heaver than their competition. Heavy axles, frames and other componenets add weight. There really is no way around it without breaking the bank.

A lightweight unit that doesn't hold up can be far more expensive than a heavy unit towed with a stout truck.

One way or another, you will pay.

[Lwiddis]

“Be sure to get the lightest trailer that fits you and equip things with a good hitch and you should be ok.“

A good hitch is necessary, yes, but it isn’t the only item needed for being “ok.” No substitutes for adequate factory payload and weight pulling ability.

[RsyS]

I have a F-150 also but have the STX HD tow pkg with the 3.5 Eco Boost. I have an equalizing hitch and have added Sumo springs, Sway Bars and HD KYB shocks to the rear. Towing my 31' #7200 TT is easy and drama free. Be sure to get the lightest trailer that fits you and equip things with a good hitch and you should be ok.

[Grit_dog]

Lots of deleted posts here recently...mine anyway, lol.
You guys can't even agree how to weigh a trailer now.
For crying out loud. New half ton is a new half ton, basically. If you're generally within the towing weight, you'd have to get pretty egregious with loading the truck and trailer to have an issue.
And trucks have built in "scales". They're called springs. If you're squishing the springs flat, you need to make some changes.

[GrandpaKip]

^This.
Using the gross weight rating of the camper will get you started at the heaviest the trailer should be.
Then figure the % (you pick between 10 and 15). You cannot have any real kind of accuracy using dry weight as a reference.

[Gdetrailer]

hussbuss wrote:
Get yourself a Sureline tongue scale. about $125.00 on E bay. Take the scale and some blocking along to look at trailers. Set the scale under the hitch and weigh it at the dealer. Then you can add for LP gas battery etc. Keep looking until you find one that will work. I use my scale all year long to check on the weight. We also use it on our race car trailers an for $10.00 and a beer or 2 we weigh other race rigs. Have fun and welcome to the forum.

hussbuss, that is a real scary way of deciding what trailer to buy, it does not give you the complete picture of the trailer..

The problem with this is you will not get the ENTIRE "dry weight" of the trailer, you are only measuring the weight of the tongue as it sits on the dealer lot. Additionally the dealer lot most likely will not be level which will also affect the tongue weight.

You really do not care what the dry weight is, go with the GVWR of the trailer, calculate 10% through 15% of the GVWR as the tongue weight and go from there. This way you are no longer GUESSING as to the weight of the trailer or tongue will end up being.

You seasoned dry weight folks love to make this a more convoluted and confusing way of figuring out what you can tow because you want to "maximize" and "justify" the largest and heaviest trailer you can possibly drag with you..

For a newby to towing, dry weight is a sure way to end up with more trailer than the tow vehicle will be able to handle when fully outfitted with gear and ready for camping.

As far as buying a $125 scale, yeah, you could do that, however you don't need pinpoint accuracy and even these dedicated tongue scales have accuracy problems (they MUST be sitting flat and level and still can vary a lot in readings).

You CAN use your bathroom scales with a 4ft long 4x4 and some blocking.. Pretty much EVERYONE has some bathroom scales which could be used. Although I have not tried digital scales, they might work as long as you can lower the tongue fast enough without dropping the tongue to get the reading.

Read HERE for a real good write up WITH photos to show you how it is done.

Even old fashioned mechanical scales cost only $12 HERE and a 6ft 4x4 might run you $20, it does work and anyone can do it. So for less than $40 you have a multi use scale with enough accuracy for what you need.

[hussbuss]

Get yourself a Sureline tongue scale. about $125.00 on E bay. Take the scale and some blocking along to look at trailers. Set the scale under the hitch and weigh it at the dealer. Then you can add for LP gas battery etc. Keep looking until you find one that will work. I use my scale all year long to check on the weight. We also use it on our race car trailers an for $10.00 and a beer or 2 we weigh other race rigs. Have fun and welcome to the forum.

[sliptap]

Everyone - thank you again for the great feedback! This has given me some great perspective as I continue my research. Understood on the points around water and weight hitch distribution, which is good to know.

I think I have what I need now and have learned more in the past month about towing than I ever imagined. Wish you all safe travels 🙂

[Boomerweps]

Plan on carrying some water on longer trips. SWMBO (she who must be obeyed) may wish to use her own BR rather than sitting on a public toilet!

[GrandpaKip]

I think you’re on the right track. If you take 13% of the gross weight rating and the resultant tongue weight fits in your calculations, you’ve got a good starting point. Per your figures, it does look as if 4000# will be your upper limit.
I would also suggest you look into an Andersen hitch which is perfect for the size camper you are looking at, is very easy to set up and weighs less than the standard bar type.
Have fun.