Holy crapolla,
I gotta print this out to decipher it.

 

Good job Tdister.

 

To be honest, it's kinda confusing me when reading back over it. It's not that difficult really, but all the words, similar looking terms and numbers kinda get to my brain when used together.

I've been told I'm not the best at simplifying things, and I believe it. Sorry, it's either come across exact or simple with me. Having them both rarely happens.

 

Ok lets try this again.

#1 GVWR
4 people @ 800
Luggage 380
Truck 5600
=6780
-7200
= 420
420 for tongue weight and can tow a 4200 pound trailer

#2 GCWR
14500 gcwr
5600 CurbWeight
= 8900 left for Truck Cargo, Passengers, trailer, trailer weight(hitch)
800 Passengers
=8100 left over
4200 Trailer & Stuff in trailer
= 3900
420 Trailer weight Hitch
= 3480
380 Luggage
= 3100 Left over that could be distributed between added trailer weight, hitch or truck cargo.

Am I right, If so..
What Im not seeing or understanding is in
Example #1 im maxed out using the with nothing left over.
Example #2 using the same weights Ive got 3100 left over to do something with

Thanks

 

I tried to come up with an analogy to compare this to, but couldn't think of anything that was not extremely flawed. I'm going to make some assumptions (they may, and probably are, incorrect, but they should convey the general idea).

We're going to say, for the sake of this discussion, that the truck's frame is what causes these limits (GVWR and GCWR both). It alone is what we are worried about stressing out.

Your frame can handle so much being pushed down on it. In this case, because of the hitch, a percentage of the weight pulling on it will be pushing down as well (if towing a trailer). In some cases, it may have much more capacity left to be pulled on (GCWR), but it doesn't have any capacity left to be pushed down upon (GVWR). The reverse can also be true.

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In your equation #2, we've decided that it seems you have 3520 lbs. left over, but do you really? Your frame can handle that much more weight if it was only going to be pulled on by it. The problem is, it doesn't only get pulled on, some of that extra weight (10%) is also going to be pushing down on the frame. You have already met the breaking point in weight pushing down on it, so you have no reserve left to actually add that extra 3520 lbs.

Because of the different ways you can load the truck/trailer, you will never get GCW, GVW and trailer weight maxed out at the same time. They are seperate, but you shouldn't exceed any of them. This wasn't Fords concern, they just wanted to let you know the maximum in each case. Consider them separate cases that all need to be considered. This is apparent when adding max trailer weight and max GVW : It exceeds GCWR. You can't have them both maxed out at the same time (in this case), it can't be done!


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Let's say you load the trailer to the maximum 8600 lbs. And your GCWR is 14,500

First estimate: 8600 + 5600 = 14200 lbs (so you are now 300 lbs away from GCWR of 14,500)

You say to yourself "Ok, I know I can't add any more weight to the trailer, I'll calculate how much more I can add to the truck itself before exceeding GVWR."

5600 + (8600 x .10) = 6460

Your thinking "OK, so I subtract the current GVW from the maximum of 7200 right?"

7200 - 6460 = 740 lbs

"OK I've got 740 lbs I can add to GVW before exceeding it. OH wait, no I don't! I just realized that, from my first estimate that, no matter what, I only have 300 lbs left over to play with before exceeding GCWR. It doesn't matter that my frame can handle more weight pushing down on it(GVW), it can't take any more weight trying to pull it apart (GCW) after adding that 300 lbs."

The good thing about doing the above equation is that now you know for sure you can add that 300 safely. It is less than 740, so you know it isn't going to exceed the weight capacity available for pushing down on the frame.

This equation, if you did load that extra 300 lbs, also happens to be the most efficent way to load the truck if trying to apply maximum weight (GCWR).

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Ford didn't care about them adding up to equal each other or always getting the maximum from every category at the same time. Neither should you. It won't happen.

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Remember from one equation I did where you have loaded your truck to 7200. No trailer, you just have that much stuff in the bed and cab that, with the curb weight, you have reached 7200 lbs. You have lots of room to spare when only considering pulling on the frame (GCWR), but the frame can't handle any more weight pushing down on it. That makes the extra GCW that's available useless, it doesn't exist now. The extra weight it seems you could add with a trailer isn't there, because a percentage of it will want to push down on the frame as well...but the frame can handle no more weight pushing down on it.