How to calculate Towing figures? Math quiz for you.
 

Okay, my heads full of these numbers can someone help:

GVWR - Total amount of weight the vehicle, contents and trailer/contents I believe right?
Tonque weight - Maximum on the hitch right?
Payload - Maximum IN the truck right? Does this include the hitch weight too?
Towing limits - Maximum towable right?


So, here's my question and the math problem:

Data from Trailer:
I'm looking at a "Trail-Lite" 30 foot trailer with slide-out (8304S) to tow that has a dry weight of 4,470 pounds and a GVWR of 5,990 pounds. It has a hitch weight of 390 pounds dry. In addition to this I will be having people in the truck and of course equipment in both the trailer and the bed of the truck.

Data from Truck:
My vehicle is an F150 Supercrew Lariat 4x4 with a 5.4L, 3.55LS, 17" wheels and Towing package. According to Ford my towing capacity is 7,100lbs and my payload is 1,640lbs (I can't seem to find a hitch weight limit - but it reasons its less than 1,640lbs). I believe my truck weighs 5,010 pounds and (I think) has a GVWR of 12,500lbs.


My math figures the following - please help if I'm wrong:
The trailer can be loaded with 1,520lbs of equipment making total trailer weight 5,990 pounds. The truck can then be loaded with 1,115lbs of cargo & passengers (the 1640lbs less my estimated wet tongue weight of 525lbs). This would bring my total loaded weight, trailer and cargo to 7,105lbs making my total vehicle/trailer/cargo at 12,115lbs.

This seems perfect - a 30.5' trailer with a slide-out and 2,635lbs of passengers/cargo all safely within my factory limits (does not take into account the aftermarket power I'm adding for easier towing).


The problem I have with this calculation is this; what if the figures were as follows:
7,100 Trailer Weight (Within spec)
600 Tongue Weight (est)
1,040 Truck Cargo (1640 less estimated tounge weight)
5,010 Truck Weight
------------
13,750lbs - this is over my estimated 12,500GVWR by 1,250 pounds


Is the 1,640lbs of Cargo weight independent of the 7,100 Towing capability? Or do I have to remain under all three numbers - the GVWR, the Towing rating and the cargo rating (this would seem to make since and then my math and the Trailer I'm looking at work fine).


Thank you for your help,
Todd
2002 F150 SuperCrew Lariat 4x4
Raider Black on Silver w/Grey Leather
5.4L; 3.55LS; 17" wheels, Skid Plates, Towing package
Chrome Steps, Factory Bed-Liner and Bed extender
Entertainment Package & Heated Bucket seats.
(Coming Soon) Chip Tuner, MAS kit and Cat-back Exhaust kit

How to calculate Towing figures? Math quiz for you.
 

>Okay, my heads full of these numbers can someone help:
>
>GVWR - Total amount of weight the vehicle, contents and
>trailer/contents I believe right?

No it should be GCWR...Gross Combined Weight Rating

>Tonque weight - Maximum on the hitch right?

Your tonque weight should be a minimum of 10% of trailer weight for a bumper tow style of trailer. 5th wheels are more like 15-20% of trailer weight.
>Payload - Maximum IN the truck right? Does this include the
>hitch weight too?

Yes


>Towing limits - Maximum towable right?

Yes
>
>
>So, here's my question and the math problem:
>
>Data from Trailer:
>I'm looking at a "Trail-Lite" 30 foot trailer with slide-out
>(8304S) to tow that has a dry weight of 4,470 pounds and a
>GVWR of 5,990 pounds. It has a hitch weight of 390 pounds
>dry. In addition to this I will be having people in the
>truck and of course equipment in both the trailer and the
>bed of the truck.
>
>Data from Truck:
>My vehicle is an F150 Supercrew Lariat 4x4 with a 5.4L,
>3.55LS, 17" wheels and Towing package. According to Ford my
>towing capacity is 7,100lbs and my payload is 1,640lbs (I
>can't seem to find a hitch weight limit - but it reasons its
>less than 1,640lbs). I believe my truck weighs 5,010 pounds
>and (I think) has a GVWR of 12,500lbs.

Change GVWR to GCWR in the above statement.
>
>
>My math figures the following - please help if I'm wrong:
>The trailer can be loaded with 1,520lbs of equipment making
>total trailer weight 5,990 pounds. The truck can then be
>loaded with 1,115lbs of cargo & passengers (the 1640lbs less
>my estimated wet tongue weight of 525lbs). This would bring
>my total loaded weight, trailer and cargo to 7,105lbs making
>my total vehicle/trailer/cargo at 12,115lbs.
>
>This seems perfect - a 30.5' trailer with a slide-out and
>2,635lbs of passengers/cargo all safely within my factory
>limits (does not take into account the aftermarket power I'm
>adding for easier towing).
>
>
>The problem I have with this calculation is this; what if
>the figures were as follows:
>7,100 Trailer Weight (Within spec)

How can this be within spec when above you stated the maximum trailer weight can only be 5,990 lbs.???

> 600 Tongue Weight (est)

You can't add tongue weight here to get total weight since it's already included with your total trailer weight.

>1,040 Truck Cargo (1640 less estimated tounge weight)
>5,010 Truck Weight
>------------
>13,750lbs - this is over my estimated 12,500GVWR by 1,250
>pounds
This should read total trailer weight + cargo + Truck Weight or 5990 + 1040 + 5010 = 12,040 lbs.
>
>
>Is the 1,640lbs of Cargo weight independent of the 7,100
>Towing capability? Or do I have to remain under all three
>numbers - the GVWR, the Towing rating and the cargo rating
>(this would seem to make since and then my math and the
>Trailer I'm looking at work fine).
That's correct you need to remain under all three numbers. BUT, I think you still be unhappy with your performance. Crusing on the flats you'll do fine...but long up hill grades be prepared for 35 MPH crawls and plenty of downshifting. I do not want to hurt anybodys feelings but I'd keep the F150's for town cruising, hauling a couple of garbage cans to the dump, 4 wheeling and generaly "looking good". When you finally get serious about towing, do not get anything less than an F250. I tow 9,000 lbs. and my originaly stock F250, 460, C-6, with 3:55 gearing was barely up to the task of towing up long grades at 5,000' elevations. It's taken $2000 worth of upgrades to make me happy...but I'm impatient and don't like driving 20 MPH below the legal limit! Deen
>
>
>Thank you for your help,
>Todd
>2002 F150 SuperCrew Lariat 4x4
>Raider Black on Silver w/Grey Leather
>5.4L; 3.55LS; 17" wheels, Skid Plates, Towing package
>Chrome Steps, Factory Bed-Liner and Bed extender
>Entertainment Package & Heated Bucket seats.
>(Coming Soon) Chip Tuner, MAS kit and Cat-back Exhaust kit

How to calculate Towing figures? Math quiz for you.
 

You may also want the double check the specs. I believe Ford specs call for a weight distributing hitch for the kind of tongue weight your looking at.

When towing go with the GCVWR. That's the total weight of the truck and trailer, fluids, passengers, tongue weight and all the goodies for a fun filled weekend, in short everything sitting on all those wheels (and the wheels too). If the GCVWR is 12,500lbs then:

12,500 GCVWR
-5,990 (max weight of loaded trailer)
_______
6,510lbs remaining.
-5,010 (Dry weight of truck?)
_______
1,500 lbs remaining for cargo and passengers.
- 400 lbs. for just two passengers.
_______
1,100 lbs. reaming for cargo.
- 600 lbs. for tongue weight (10-15% of trailer weight)
_______
500 lbs remaining. (not much payload capacity remaining)

The weight you stated for your truck seems a little on the light side. I would fill up the gas tank and load it up with everything you normally carry and have it weighted at a public scale. Ford quotes payload capacity and towing capacities based on a "standard" truck, usually a standard cab, 4x2 truck. Crew cab, 4 wheel drive and other factory options are considered payload. The only way to be sure is to have the truck weighted and get a real number, not the numbers from Ford.

A friend of mine had the same truck as yours and went out and got a 30ft trailer and slapped in on the back and took off (also used a weight distributing hitch). After the second trip he sold the F-150 and got a F-250 Super Duty with a V-10. He is much happier now pulling that trailer through the Sierra mountains.

F-150 is a light duty vehicle. Frame design and brakes as well and engine size, rear end gears and tires all come into play. The only way to improve the towing capacity of a 1/2 ton truck is to get a 3/4 or 1-ton truck.

How to calculate Towing figures? Math quiz for you.
 

Thanks for the reply Deen & Dan.

Deen:
"How can this (7,100lbs) be within spec when above you stated the maximum trailer weight can only be 5,990 lbs.???"

Sorry if I was unclear, I was presenting a different scenario (a hypothetical trailer @ 7100lbs) to help you understand where I was having difficulty with the numbers. Your response that I need to stay under all three limits explained it fine.


Dan:
My four family members weigh about 450lbs (two young boys 5 & 2), so that leaves us just 450lbs of Cargo in your figures, but there's also the 1,520 pounds in the trailer in your calculation. So, that is nearly a ton of gear (1,970lbs); plenty for a week. Though, now I'm concerned about what my truck really weighs with all the options . . .

I do agee, an F250 would've been better for towing; and suprizingly only $800 more upgrading to the V10 and staying comparibly equiped to the F150 (we were going to buy this instead once we saw how inexpensive it was). The problem here was my garage size and driveway length. The F250 is longer than my driveway and my Garage (I live in a cul-de-sac) and I couldn't keep it on my property unfortunatly. The extended cab wasn't an option as there wouldn't be enough room for my family.

Camping is actually an afterthought of the F150 purchase. We had an Expedition prior to this F150 SuperCrew and were looking at a tent trailer. I just noted now that I have a larger towing capacity with the F150. And, newer technology (aluminum frames) is keeping larger towables in my range.


What I want is the largest - fully equiped - trailer I can buy that will allow me to fit the factory limit of my F150. I'm willing to spend to $30k on a high-quality, fully-quiped, travel trailer that can be towed relatively easiliy by an F150.

I'll be lucky if we use this trailer more than 4 times in a year and trips will be limited in up-hill travel; we might pull it to Lake Tahoe from Sacramento once a year. But, most would be flat-land to the coast; maybe to Southern CA once every couple years.


Do you really think that if I went to my full 12,500GCWR that I would have issues towing this at highway speeds given I'll probably be adding another 20% of power with a chip tuner, MAS kit and Cat-back exhaust system? I could change the gearing (say 4.11 from 3.55), but I really don't know if that's necessary given the rarity of my towing.


Thank you,
Todd
'02 F150 Lariat 4x4 SuperCrew
Raiders Black & Silver 2-tone w/Grey Leather
5.4L, 3.55LS & 17" wheels
Skid Plates, Towing Package
Chrome Steps, Factory Bedliner
Heated Buckets & Rear Entertainment System

How to calculate Towing figures? Math quiz for you.
 

Your biggest bang for the buck will be spending the $1200 to change your gearing to 4:11's. Get the trailer you were talking about (it appears you'll just be under your GCWR), give it a good tryout on your next camping trip, then decide if you can live with it. If not, I'd install headers and a K&N filter first...then the gearing. I may be mistaken but most aftermarket chips are designed more for full-throttle applications.
Good luck, Deen

How to calculate Towing figures? Math quiz for you.
 

Weight the truck first. Put the whole family in and all the stuff you normally carry, full tank and have it weighted. My registration said my truck weighted 4,000lbs (got it used and with commercial plates). I went by that for a long time, then I weighted it and found out it really weights 5,000lbs (5,300lbs with the shell). Weight it and go from there. Steeper gears in the real whould also be a big help in towing if you can live with them when not towing.

How to calculate Towing figures? Math quiz for you.
 

Thanks for all your help Deen & Dan. I'll probably go the route of buying a trailer I really like that will bring me close the the GCWR of the F150 . . . knowing that I can increase my GCWR with a simple change to the 16" wheels (of course I would then need to recalibrate my speedo) if I scale in over 12,500lbs loaded.

Dan, you're right; with all the options on my F150 I'm probably over the stated 5,010lbs in my manual (that doesn't include the Chrome steps, bed-liner, skid plates, Entertainment package, bucket seats, 17" wheels instead of 16" or the towing package). Me, the wife and kids weigh in about 450lbs - will probably grow to 550lbs before I upgrade in about 3years. My guess is with fuel, passengers and options I'm weighing in (vehicle only) at 6,000lbs. Leaving me just 6,500 for trailer and cargo (7,000 if I downgrade the wheels to the 16" and move to LT instead of P rating). That should be perfect with the trailers GVWR at about 6,000 anyhow - the last 500 (1,000 if wheel switch) would need to go in the truck bed. Confused now? hee hee, I'm actually starting to get this, but you really have to write it out to get it as the tongue weight counts against the GCWR and the GVWR of the F150 (i.e. part of its 1640 payload).


Here's my plan:

A) Find some scales near home, weigh truck with family/full tank of fuel.
B) Calculate what my GCWR would be after taking into account weight from (A).
C) Buy a Travel Trailer with a GVWR rated near (B)'s total (no higher than 6500lbs).

From here I'll be pretty much stuck with my decision. However, I can still plan and try to stay within the GVWR of my Truck and GCWR of truck/TT by doing the following:

X) Find scales to weigh TT loaded with water (fresh, gray & black) standard supplies (bedding, kitchen equip, supplies, etc).
Y) Find Tongue (hitch) weight of TT when wet. Add this total to (A) and subtract from the GVWR of my F150 (I think this is about 6,650 but don't know - just took the 1640 advertized payload and added to 5010 advertized weight).

X will give me the cargo capacity of the trailer and Y will give me the cargo capacity of the truck (of course some of X will impact the tongue weight and therefor Y - but this is minimal, say 10% of Y to be safe).

Being as I kept the GVWR of the TT at 6,500 or less; the totals of X & Y should be right at 12,500lbs (as part of X will include the tongue weight of about 500lbs of Y).


Example (estimates to see if I get it):
5,800 F150 Wet w/family (estimate)
600 Hitch Weight (estimate)
250 Cargo in Bed (max based on above estimates)
------------
6,650 GVWR F150 (estimated max based on Ford's weight/cargo capacity)

5,500 Trailer Wet (water, bedding, kitchen supplies, etc)
950 Cargo in TT
-----------
6,450 Travel Trailer (50lbs under GVWR to stay under GCWR below)

6,650 F150/Cargo/Tongue weight
5,850 TT axel weight (600 pounds is on the hitch in example right?)
-----------
12,500 GCWR; Meets factory standards and should be legal in all states.

Total cargo estimated at 1,200 pounds (not bad for food, clothes, fishing gear, toys, etc).

Head spinning yet? I think I got it though; please let me know any errors.

Last step in plan; See how it tows with the add-ons I have coming (already ordered the chip tuner and the MAS kit and am doing a cat-back dual exhaust kit). If too anoying, I will change gears to 4.11's (not a problem as our daily commute is just 5 miles each way and no freeway).


Given some posts I've seen with people pulling 4,000lb TT's with mini-vans I think I should be doing fine. Not to mention I've seen 6cy Explorers with TT's and boats and I know they've GOT to be over their GCWR if I hit mine nearly stock.

Check my math, scenario above, let me know if anything sticks out. I'll be realatively safe and won't tow at excessive speeds or in high winds. I start slow (short trips) and see how it goes. I really want this quallity family time - it is important to me. If I like camping enough I can get a bigger truck/camper when we move in about 2-3 years.

Thanks again for all your help!
Todd
'02 F150 SuperCrew 4x4 Lariat
5.4L, 3.55LS, 17" wheels Towing Package
"Looking for something to tow"

How to calculate Towing figures? Math quiz for you.
 

Okay, I weighed my F150; completely FULL of gas (overfilled tank and drove less than 300 feet to the scales). Also, I wasn't thinking and drove it through the car-wash before I weighed it, so it was literally Wet (laughter).

Here's the weight:
#5,420 F150/Full tank and car seat (no passengers - I had to get out to see scale)
#3,040 Front Axle
#2,380 Rear Axle

This make my maximum Trailer at #7,100 as my family weighs #470;

#5,420 F150/Car Seat/Full tank of fuel
# 470 Weight of Me/Wife/Boys
# 850 Hitch (12% of 7,100 TT)
------------
#6,750 Hits the GVWR of the F150
#6,250 Axle weight of TT (#7,100 less the #850 Hitch)
------------
#13,000 GCWR; right at my limit with 16" wheels


I've found 9 TT's that I like with GVWR's that range from #4,682 to #7,100 and lengths from 28-31.5 feet. Examples:
28' GVWR = 7,000 http://www.kz-rv.com/frontier/frontier_2802p-f.php
30' 9" GVWR= 7,000 http://www.campersfactoryoutlet.com/traillite-8304s.html
31' 6" GVWR= 6,455 http://www.forestriverinc.com/rk/rk_ettt.asp?name=4

I'll probably pick one that is #6,500 or less. In any case, I'll have to carry all my gear in the TT as my F150 will be close to or at the GVWR (even with the #4,682 TT my GVWR would be at #6450 leaving me only #300 of cargo/gear in the truck).

The cool part is that depending on what trailer I pick I can put up to #2,500 of cargo/gear in the TT; this is important since the F150 can't carry much more than the hitch and my family.

Thanks for your help,
Todd, Melissa & the Boys
F150 Lariat Supercrew 4x4 #5,420 wet
5.4L, 3.55LS, 17" wheels
GVWR #6,750; GCWR #12,500
Capible of towing a #7,100TT with #850 of hitch and my family in the cab

How to calculate Towing figures? Math quiz for you.
 

More things to check...

I own a 28' Coachman travel trailer and it has just over 2,000 pounds of useful load. However, some of the trailers I looked at prior to my purchase had really low useful loads... Some well under 1,000 pounds.

Check inside the kitchen cabinets for the actual weight of your trailer. The factory usually glues/tapes a sheet there which gives you the empty weight of that specific trailer with all of the options it has installed. Compare this number to the max weight on the sticker located on the front left side near the tongue (outside). You might be suprised... I was and walked away from several brands.

Edmo

How to calculate Towing figures? Math quiz for you.