Do you have to Know the Rear Axle Weight, Not Capacity, to Figure Out How Much a Truck Can Tow

Question:

In the article by Mr. Polk,Before you Buy RV for Safe trailer towing, there is a provided method to determine if the weight of the trailer and tow vehicle match up. The second part of the configuration requires the actual rear axle weight.Not capacity I have not found any figures which are applicable to this requirement. Can you direct me to a site , or provide the rear axle weight of a 2014 F150 Super crew 4x4, and the 2014 F250 Super Crew 4x4 . 3.55 or 3.73 rear end

asked by: Gordon C

Helpful Expert Reply:

Knowing the weight of the tow vehicle axle is not really relevant, or at most rarely relevant, to determining how much the truck can tow. What matters is the truck manufacturers axle capacity, gross trailer weight capacity, and gross combined weight rating. In my years of working in this industry I have never heard of the axle weight on the tow vehicle being needed to determine anything. Only the capacities.

With that said I also asked around here to get some other opinions on the subject and was met with basically the same response as above. But, if it comes down to the very maximum the truck can tow and the trailer is right on that edge then it could be necessary to determine the axle weight.

But at the same time usually the weight of the axle is factored into how much it can carry (since it has to carry itself as well), its gross capacity. Ford might be able to tell you if the capacities for those axles has already factored in the weight of the axle itself or not.

The capacities of the truck will be listed in the owners manual and/or in the sticker in the door jamb, the same sticker that also says how much air pressure goes in the tires.

The gross combined weight rating is the total amount that the truck and trailer can weight together when loaded and ready to tow. This includes passengers, luggage, fuel, water, propane, and anything else carried in the trailer or truck.

The gross trailer weight capacity is how much a trailer can weigh for that particular truck. The gross axle capacity of the truck axles is how much weight the axles can carry.

So let's say that the axle capacity is 5,000 pounds and the weight in the truck bed above and/or behind the rear axle plus the tongue weight of the trailer is 3,500 pounds. There would be no need to determine axle weight because it isn't even close and the axle is not going to weigh 1,500 pounds.

I am certain Mr. Polk means well and having read through some of the literature a lot of what he says is very helpful. But knowing the weight of the axle is not something normally covered or asked of people to determine, in part because of how difficult it is to do so. I haven't even seen a vehicle owners manual that has ever mentioned that.