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Are my calculations wrong?

Kiddikop1
Explorer
Explorer
I think I goofed big time. After reading a lot about the Ecoboost, and having owned a 5th wheel with an F350 in the past, I decided to go with the smaller Ecoboost, and was impressed with the high towing figures. So, I got this nicely tricked-out truck, and much to my dismay, after reading many many posts here and on other forums, I am just worried silly that my truck is not up to snuff. I want desperately to be able to pull a 5ver, knowing the limitations with a short-bed (I had a Pullrite on the F350 and loved it), but it seems like this is not possible with the numbers Iโ€™ve computed. So, please help me out by checking my figures, and suggesting any possible solutions.
2013 Ecoboost, short-bed, FX4
3.73, Max Tow Package, 7650 GVR Package
GCWR=17,100
Max Loaded Trailer Weight=11,200
Rear GAWR=4050, Front GAWR=3750

I weighed the truck, loaded with fuel (36 gal), myself and passenger, supplies, but no hitch
Loaded weight of truck came to 6500
Unfortunately this was on a waste management co. scale that did not have a way to get rear axles.

If I add 200lb. to my truck weight (for a 5ver hitch), it comes to 6700. I subtracted that from the GCWR of 17,100 and got 10,400.
But then I subtracted the truck weight from the GVWR and got 950. I then divided that by .18 and got a final reading of 5277 lbs that I can safely tow.

Is this right? If so, it looks like a 5ver is out of the question because I doubt if there are any out there that would come in at that weight and be anything decent.
I pray that I am doing these calculations wrong. Even when I divided the 950 by .15 (for a regular trailer hitch), I still only have 6333 lbs to tow.
Something just seems terribly wrong and unfair to me. Donโ€™t wanna whine because I do have this wonderful new truck, drives like a dream, getting over 17 mph, smooth ride, but I have just retired and was looking forward to getting about a 30 ft. 5ver or trailer and striking out cross-country. If these numbers are right, looks like Iโ€™ll have to settle for a hybrid or a pop-up!

Any suggestions would be helpful. And thanks for all the posts. I have been lurking on the forum for years but never felt I had enuf expertise to contribute anything useful. Maybe some day I can pay-back to all you folks who take the time to help those of us who are wandering around in towing la-la land!
14 REPLIES 14

BenK
Explorer
Explorer
Maybe this will help un-confuse you on the numbers, which is really what those
acronyms are

  • GVWR, Gross Vehicle Weight Rating and applies to both tow vehicle and trailer (fiver or tongued)
  • GAWR, Gross Axle Weight Rating and normally need a suffix of prefix of 'front' and 'rear'
  • GCWR, Gross Combined Weight Rating and is the sum of the tow vehicle weight (which includes EVERYTHING loaded onto and into the TV

    PLUS

    the trailer (fiver or tongued)


Those ratings are a equal to or less than number



The rest of it is having actual weights to then use simple math
to figure out where you are in reference to those ratings (acronyms)

The performance (mainly at the extreme...like when you need to make
an emergency maneuver to avoid something) and longevity a bit past
the OEM's warranty period.

Performance can also be viewed as the ability for that tow vehicle
to manhandle that trailer based on the GCWR.

It's not to say that the wheels will instantly fall off if over those
ratings, but they will sooner and not perform as the OEM promised you
via their published specifications
-Ben Picture of my rig
1996 GMC SLT Suburban 3/4 ton K3500/7.4L/4:1/+150Kmiles orig owner...
1980 Chevy Silverado C10/long bed/"BUILT" 5.7L/3:73/1 ton helper springs/+329Kmiles, bought it from dad...
1998 Mazda B2500 (1/2 ton) pickup, 2nd owner...
Praise Dyno Brake equiped and all have "nose bleed" braking!
Previous trucks/offroaders: 40's Jeep restored in mid 60's / 69 DuneBuggy (approx +1K lb: VW pan/200hpCorvair: eng, cam, dual carb'w velocity stacks'n 18" runners, 4spd transaxle) made myself from ground up / 1970 Toyota FJ40 / 1973 K5 Blazer (2dr Tahoe, 1 ton axles front/rear, +255K miles when sold it)...
Sold the boat (looking for another): Trophy with twin 150's...
51 cylinders in household, what's yours?...

Kiddikop1
Explorer
Explorer
Thanks for all the advice. I have not yet even come close on deciding what to buy. Actually I will be going to the Hershey, Pa show this fall and will start getting ideas for floorplans, etc. I also plan to weigh the truck at a better scale that will give me the axle weights. Maybe then I'll be better prepared for the show and the dealers who are going to be telling me I can tow anything. Although I am still somewhat confused on the numbers (seems that there are several different formulas that have been suggested), I believe that I am getting a realistic picture now. In no way do I want to go over the weight allowances. Life is too short to take chances just to gain some room for stuff that I can probably do without anyway. Thanks for all your suggestions. I will probably get back to yall after I get more accurate weights.
Be safe out there!

mkirsch
Nomad II
Nomad II
You can park the truck with one axle on the scale and one off to get a per-axle weight. Just drive on until the front is on the scale, get a weight, then drive off the other side until the rear is on the scale, and get a weight.

There is no realistic way to tow even the smallest 5th wheel with this truck and stay within GVWR. The best you can hope for is to not exceed the individual axle ratings.

Putting 10-ply tires on half ton trucks since aught-four.

BenK
Explorer
Explorer
BurbMan wrote:
If you add back in the 200 lbs for the 5er hitch, that leaves you with 1150 available payload, plenty to handle the tongue weight of just about any 30' travel trailer. 5ers usually put 20% on the pin and TTs put 12-13% on the tongue, so would likely be able to tow a bigger TT than a 5er.

As Jimlin pointed out you can likely stretch that with higher-rated tires and possibly air bags or Timbrens on the rear.

To answer your question, your numbers look right, and good thing you are doing the math now rather than after the RV salesman sells you that big honkin' trailer.....

You'll be able to get a nice rig that's bigger than a hybrid or pop-up, you just need to keep a close eye on the numbers.

On a final note, pay attention to the loaded weight of any trailer. On average you will add 1000-1500 lbs of stuff to either a 5er or TT, so be sure to add that to the dry weight of whatever trailer you are looking at. Most of the 5er's storage is in the basement up front, so a lot of that goes right to pin weight.


Ditto, but wonder if the OP is only looking for confirmation of what
he wants to buy...

Repeat the best is go out and actually weigh his TV axle by axle instead
of guess what his loaded weight will be

That is the only way to know where 'that' TV is in reference to it's
ratings

Then the basis for figuring out what the true MTWR for a Fiver or Tongued
will be
-Ben Picture of my rig
1996 GMC SLT Suburban 3/4 ton K3500/7.4L/4:1/+150Kmiles orig owner...
1980 Chevy Silverado C10/long bed/"BUILT" 5.7L/3:73/1 ton helper springs/+329Kmiles, bought it from dad...
1998 Mazda B2500 (1/2 ton) pickup, 2nd owner...
Praise Dyno Brake equiped and all have "nose bleed" braking!
Previous trucks/offroaders: 40's Jeep restored in mid 60's / 69 DuneBuggy (approx +1K lb: VW pan/200hpCorvair: eng, cam, dual carb'w velocity stacks'n 18" runners, 4spd transaxle) made myself from ground up / 1970 Toyota FJ40 / 1973 K5 Blazer (2dr Tahoe, 1 ton axles front/rear, +255K miles when sold it)...
Sold the boat (looking for another): Trophy with twin 150's...
51 cylinders in household, what's yours?...

myredracer
Explorer II
Explorer II
Don't believe any of the highly inflated towability numbers the various manufacturers are flogging these days. It's almost scary what they are doing. The "1/2 ton towable" label has been around for a while and now I see that KZ is using a "1500" and "2500" designation on their trailers for 1/2 and 3/4 ton tow vehicles.

KZ is now listing a 34' Durango 5th wheel with a dry weight of over 8,000 lbs as being suitable for a 1/2 ton. I'd like to now how any 1/2 ton truck can handle that, even with a HD tow package. Am I missing something? Our 3/4 ton truck would not even be able to handle this trailer on the basis of payload. I also see that KZ seems to have lowered the 12K+ GVWR for this (or similar 34' model they have) to 10,800 lbs GVWR. I am guessing that this is to make it appear more tow-able by a 1/2 ton? I am pretty certain if this is the case, the loaded weight of the trailer will be pretty close to the 10.8K GVWR and not leave room for a tank of fresh water even (happened on our current trailer). And what about the RAWR with this trailer on a 1/2 ton?? They, as are most (or all??) are silent on payload and RAWR limits and calculations.....

The trailer manufacturers are all playing a weight numbers game and regretfully you have to go onto forums to educate yourself.

ependydad
Explorer
Explorer
skipnchar wrote:
In order to tow a 5th wheel of any size you need to have ordered your truck with the HD Payload option (8200 lb. payload). YOu can still tow a 5th wheel but it will just need to be a smaller one than otherwise would be possible. Payload is the main thing to look at for 5th wheel towing regardless of WHAT size truck you are using. People are quick to point this out with half ton trucks but it is just as much a factor with 3/4 ton trucks but many just ignore it in that case.
Good luck / Skip


I find myself commonly agreeing with Skip. 1/2 tons just don't have the payload needed to tow much *if* you're going to adhere to all ratings.

The fact that you wanted rear axle weights already says that you're willing to overload the GVWR and limit yourself to rear axle + tire load capacity. A lot of people do it. Not my way, though.
2017 Spartan 1245 by Prime Time
2018 Ram 3500 Crew Cab DRW w/ 4.10 gears and 8' bed
FW Hitch: TrailerSaver TS3
Learn to RV- learn about RVing - Towing Planner Calculators - Family Fulltiming FB page

BurbMan
Explorer II
Explorer II
If you add back in the 200 lbs for the 5er hitch, that leaves you with 1150 available payload, plenty to handle the tongue weight of just about any 30' travel trailer. 5ers usually put 20% on the pin and TTs put 12-13% on the tongue, so would likely be able to tow a bigger TT than a 5er.

As Jimlin pointed out you can likely stretch that with higher-rated tires and possibly air bags or Timbrens on the rear.

To answer your question, your numbers look right, and good thing you are doing the math now rather than after the RV salesman sells you that big honkin' trailer.....

You'll be able to get a nice rig that's bigger than a hybrid or pop-up, you just need to keep a close eye on the numbers.

On a final note, pay attention to the loaded weight of any trailer. On average you will add 1000-1500 lbs of stuff to either a 5er or TT, so be sure to add that to the dry weight of whatever trailer you are looking at. Most of the 5er's storage is in the basement up front, so a lot of that goes right to pin weight.

JIMNLIN
Explorer
Explorer
Your F150 came with the 7650 GVWR and small 4050 RAWR/p tires which will limit how much load the trucks axles can carry.

The F150 HD package has a 8200 GVWR with larger 4800 RAWR/E tires and wheels for carrying another 700-800 lbs of pin weigh.

Your F150 rear axle may weight 2500 lb when empty which leaves the truck with a 1550 lb payload (4050 RAWR minus 2500 lbs = 1550 lbs). Actual numbers depend on actual scaled weights.

I would look at 5th wheel trailers with a 900-1100 lb dry pin weights.
"good judgment comes from experience, and a lot of that comes from bad judgment" ............ Will Rogers

'03 2500 QC Dodge/Cummins HO 3.73 6 speed manual Jacobs Westach
'97 Park Avanue 28' 5er 11200 two slides

BenK
Explorer
Explorer
Below is my diagram showing how the specifications/limits/ratings system works

Best to weigh your setup axle by axle fully loaded ready to go. If you don't
have one or the other, then use their GVWR's as the potential max...if you load
everything like most do...few are truly light in the stuff they load

Also, decide if you believe in the ratings or not.

If not, then do whatever but a new 2013, assume still under warranty. so know
that if they find out over loaded, warranty might be denied (I would if I was
the OEM)

If yes, then check out the below diagram, gather the specifications for 'your'
TV and plug in the actual weights to do the simple math.

You have found out that it is not all about go, but the ratings are the true
measure. You will get tons of 'sure you can', etc, etc advice, but there is only
one person responsible for the setup and that is the driver, who might not be
the OP, but a buddy or spouse. Then the OP should ask themselves if the advisers
would pay for any overload break down?

I do not advise with the 'your are good for it', 'sure you can', 'no you can not'
but provide the metrics for the OP's to figure it out themselves...I have to
sleep at nite as I take providing advice seriously...

This is NOT a half ton can't tow anything...everything can tow
and then they also have specifications/limits/ratings on what they
are 'rated' to tow.

Just that half tons have lower ratings and head room than bigger trucks

Then note that there is a huge spread on 'half tons'. From less than
6.2K GVWR to over 8.1K GVWR (I call them fake half tons). So many
get bit by hearing/reading of a 'half ton' doing whatever but miss
or the poster didn't say they have one of those fake half tons. I've
gotten several PMs about that and one guy so mad he wanted to sue the
guy telling everyone a half ton can, but he had one of those fake
half tons...so this guy who PM'd me burned up his diff towing what
he though all half ton's can because one guy said he does and advise
that guy he too could...





another thread titled: New guy needs help

BenK wrote:
Welcome to the forum !

First decide if you believe in the OEM specifications/limits/ratings or not

If not, then do whatever but note that if there is warranty left...the
OEM may be denied. If no warranty, then you have taken the OEM off the
liability hook

If yes, then read up and ask lots of questions

There is a huge difference in how a question is asked or answered
'Can do' is way different from 'should do' or 'rated for'



The specifications, limits and ratings is a 'system' and most take
a single rating as an absolute or out of context....like your reference
to your TV's MTWR (Max Tow Weight Rating)

Meaning that, those MTWR's are only a true rating within the fine
print of the OEM's specifications

Meaning that they derived those MTWR's from a 'curb' weight TV, which
is the 'stripper' model with no options other than the tow option
and one 150lb driver. Some full fluids, others partially filled

Best is to weigh your TV's fully loaded...axle by axle. That is the
only way to figure out your 'true' MTWR

You should gather these ratings for both your TV's

GVWR
FGAWR
RGAWR
GCWR

Then do the simple math to figure out your true MTWR

Some come here looking for confirmation of what they want to hear
or what they have already decided on....they WILL get many advisers
that will do exactly that...just ask yourself if those advisers will
provide the funds for warranty or whatever cost an overloaded TV
might suffer

This image shows how the ratings system looks like in graphical form

howmuchcanitow
-Ben Picture of my rig
1996 GMC SLT Suburban 3/4 ton K3500/7.4L/4:1/+150Kmiles orig owner...
1980 Chevy Silverado C10/long bed/"BUILT" 5.7L/3:73/1 ton helper springs/+329Kmiles, bought it from dad...
1998 Mazda B2500 (1/2 ton) pickup, 2nd owner...
Praise Dyno Brake equiped and all have "nose bleed" braking!
Previous trucks/offroaders: 40's Jeep restored in mid 60's / 69 DuneBuggy (approx +1K lb: VW pan/200hpCorvair: eng, cam, dual carb'w velocity stacks'n 18" runners, 4spd transaxle) made myself from ground up / 1970 Toyota FJ40 / 1973 K5 Blazer (2dr Tahoe, 1 ton axles front/rear, +255K miles when sold it)...
Sold the boat (looking for another): Trophy with twin 150's...
51 cylinders in household, what's yours?...

goducks10
Explorer
Explorer
Try one of these http://www.forestriverinc.com/FifthWheels/Flagstaff/default.aspx?page=floorplandetails&floorplanid=3.... You will have to be diligent in packing. IMO you would be better served with a TT. From my past experience when I had a 10 F150 Maxtow with the 7650 GVW and 1857 CCC, I could never make the numbers work when 5'er shopping. I know what we pack and it's around 1200+lbs. Adding that to the dry sticker weights (not brochure weights) and using 20% as a starting point on the pin I was always right at or slightly over the RAWR and GVW. There are guys on here and also on the F150 Forum that tow 5'ers with 1/2 tons. I find that some are over weight and others are close. I prefer to not be at the ragged edge and to have a sizable weight cushion which allows me to be able to take what I want camping. There's nothing worse than being maxed out.

bikendan
Explorer
Explorer
if you didn't get the HD/Max payload package, you're going to be stuck with only the smallest 5th wheels out there.
Dan- Firefighter, Retired:C, Shawn- Musician/Entrepreneur:W, Zoe- Faithful Golden Retriever(RIP:(), 2014 Ford F150 3.5 EcoboostMax Tow pkg, 2016 PrimeTime TracerAIR 255 w/4pt Equalizer and 5 Mtn. bikes and 2 Road bikes

rhagfo
Explorer III
Explorer III
X2 to the statement from SkipnChar!

It is necessary to order a Max/Max F150 to pull a 5er of any size with a F150. If you use to pull with a F350, I doubt even if you would have gotten the Max/Max you would fine the experience enjoyable. Even with a 5er , you will get to the point of the Tail wagging the dog!!
Russ & Paula the Beagle Belle.
2016 Ram Laramie 3500 Aisin DRW 4X4 Long bed.
2005 Copper Canyon 293 FWSLS, 32' GVWR 12,360#

"Visit and Enjoy Oregon State Parks"

TomG2
Explorer
Explorer
A few fifth wheel trailers will work for you although the makers like to sell the heavier models. Reading through your post, I was wondering if and when you would get to payload, which is the real place to start, not the television commercials touting 11,000 plus towing figures. Good thing you did some discovery before purchasing any trailer. Travel trailers can be a lot of fun too.

skipnchar
Explorer
Explorer
In order to tow a 5th wheel of any size you need to have ordered your truck with the HD Payload option (8200 lb. payload). YOu can still tow a 5th wheel but it will just need to be a smaller one than otherwise would be possible. Payload is the main thing to look at for 5th wheel towing regardless of WHAT size truck you are using. People are quick to point this out with half ton trucks but it is just as much a factor with 3/4 ton trucks but many just ignore it in that case.
Good luck / Skip
2011 F-150 HD Ecoboost 3.5 V6. 2550 payload, 17,100 GCVWR -
2004 F-150 HD (Traded after 80,000 towing miles)
2007 Rockwood 8314SS 34' travel trailer

US Govt survey shows three out of four people make up 75% of the total population