Quick & Dirty Formula to use when shopping for a Tow Vehicle

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Ride Everything

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Hello all- I'm in the market for a new truck (again) and new trailer, and I was hoping to get some advice on a simple, safe, quick and dirty formula to use when shopping for a tow vehicle and trailer.  I've read all the formulas, etc, to calc out everything, but it would be nice to be able to quickly come up with something when you're out shopping...

Thanks!
 

Carl L

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If you are shopping over a single year, take along a downloaded print of the Trailer Life tables of that year, or the range of years.    Discount their ratings by 20% if you would tow in the mountain or Pacific west.
 

Ride Everything

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Ok so, let's say I'm in the market for a 2005 F-250 V-10.  With the right axle, the tow rating would be 12,500.  Take off 20%, now I'm down to 10,000 lbs.  In that case, I should be looking at a trailer with a GVWR of 10,000 lbs??

Thanks
 

N Smock

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<Ok so, let's say I'm in the market for a 2005 F-250 V-10.  With the right axle, the tow rating would be 12,500.  Take off 20%, now I'm down to 10,000 lbs.  In that case, I should be looking at a trailer with a GVWR of 10,000 lbs??>

Nope. Even if the trailer weight comes in OK you still have to factor in the pin weight that the trailer will drop in the bed or the ball weight if it's a TT. Like Carl said take the guide and write down the equations and take a calculator along. It is real easy to overload a truck. FYI if you are looking at GVW trailers of 12500 I think you should look at the diesel not the gas. The gas will cost you bucks empty or loaded. Just my opinion.


Nelson
 

Carl L

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For a TT, tongue weight is significant on from the standpoint of being too light for good trailer stability -- less than 10% of trailer weight.   Travel Trailer weight is distributed evenly to both axles of the tow vehicle by the weight distributing hitch system which is manditory for TT towing.  The overall tow rating of the truck will take care of that.

For that matter overall tow rating should handle 5th wheel towing also.   The pin weight might be of concerned with light weight trucks in the half ton trucks or with really huge trailers with anthing less than a medium duty truck.   Compare it with the rear axle weight and weight rating as a secondary check -- sort of a belt and suspenders check -- or just take a 10%-20% safety factor and call it a day.

In any case, tongue/pin weight is merely the portion of trailer weight that impinges on the tow vehicle and not its own axles.  It should not be double counted in tow ratings, it is already in there.
 

Ride Everything

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When we say Hitch weight, is that the hitch on the truck, or the trailer?  If if it's the trailer's hitch, does that mean the weight given in the trailer doesn't include this weight?

Good grief, this is confusing.  It shouldn't be this difficult...I must be making more out this towing capacity issue than I should.
 

Carl L

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[When we say Hitch weight, is that the hitch on the truck, or the trailer?  If if it's the trailer's hitch, does that mean the weight given in the trailer doesn't include this weight?

A trailer has a weight.  That weight is supported on the trailer axles and on the truck hitch ball that its coupler rests upon.  The percentage of trailer weight that rests upon the ball is called tongue or hitch or pin weight.  On a travel trailer, 85-90% of the trailer weight rests on the trailer axles and 15 to 10% on the hitch ball.    Fifth wheel traler percentages are 80-85% on the axles and 15-20% on the truck hitch.

Good grief, this is confusing.  It shouldn't be this difficult...I must be making more out this towing capacity issue than I should
.

You are.  Sit down, pour yourself some light refreshment and relax.  All you need is two numbers.  The tow rating of the truck you will tow with is one.  The Gross Vehicle Weight Rating of the trailer is the other.  That is all.  With those two numbers you can make your choices.  I like to discount the tow rating a bit to allow bit of safety margin as the truck ages and things get worn and out of tune.  I use 10%.  Don't like 10%?  Use what ever makes you comfortable.

Out here in the mountain and Pacifilc West, I heartily recommend 20% discount based on our long steep grades and high altitudes.  Engines lose 3% of rated HP per thousand feet of elevation.

Discount the tow rating by whatever factor you use.  Take that number and find a trailer with a GVWR less than that.
 

N Smock

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When we say Hitch weight, is that the hitch on the truck, or the trailer?  If if it's the trailer's hitch, does that mean the weight given in the trailer doesn't include this weight?

The weight of the hitch for a fifth wheel is included in the truck as part of it's ready to roll weight. The ready to roll weight is; truck, driver, passenger, hitch, fuel dogs and all else no trailer. This weight is best determined by scales. The truck has a GVW, for a 3/4 ton about 9,200 #, so from the GVW subtract the ready to roll weight and you have the max pin that you can deal with, the max pin should be a loaded pin not empty. The loaded pin can be computed by finding the pin percent pin/UVW UVW=Unloaded Vech. Weight. Apply that percent to the trailer GVW to find the max loaded pin weight. This description is simple and ignores the rear axle load which may be exceeded in this simplified calculation.


Nrlson
 

todd

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Hitch weight (or Pin weight) is the amount of "Trailer" weight sitting (being applied) on the hitch or pin.

 

Ride Everything

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Carl Lundquist said:
A trailer has a weight.  That weight is supported on the trailer axles and on the truck hitch ball that its coupler rests upon.  The percentage of trailer weight that rests upon the ball is called tongue or hitch or pin weight.  On a travel trailer, 85-90% of the trailer weight rests on the trailer axles and 15 to 10% on the hitch ball.    Fifth wheel traler percentages are 80-85% on the axles and 15-20% on the truck hitch.
.

You are.  Sit down, pour yourself some light refreshment and relax.  All you need is two numbers.  The tow rating of the truck you will tow with is one.  The Gross Vehicle Weight Rating of the trailer is the other.  That is all.  With those two numbers you can make your choices.  I like to discount the tow rating a bit to allow bit of safety margin as the truck ages and things get worn and out of tune.  I use 10%.  Don't like 10%?  Use what ever makes you comfortable.

Out here in the mountain and Pacifilc West, I heartily recommend 20% discount based on our long steep grades and high altitudes.  Engines lose 3% of rated HP per thousand feet of elevation.

Discount the tow rating by whatever factor you use.  Take that number and find a trailer with a GVWR less than that.

Whew!  that was it??  Thanks everyone for the input.  Time to go shopping......AGAIN!
 
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