Tongue Weight Rating

Ron Gratz wrote:

The Owners Manual clearly states the WDH should be adjusted to cause the front end to return to its unhitched height.
That would cause about 80% of the tongue weight to be carried on the TV and would cause about 20% of the tongue weight to carried on the TT's axles.Ron

The Ford manual for my truck states that the WDH should be adjusted to bring the truck back up to HALF the distance between unloaded and with no WDH.

Ron Gratz wrote:

lbrjet wrote:
The Sherline TW number + the weight of the hitch itself should be less than 895lbs.

Do you have a link to any manufacturer's statement which says the weigh of the WDH must be included?
I find nothing in the 2006 Expedition Owners Manual which states you must allow for the weigh of the hitch itself.
I find nothing anywhere else which says you must allow for the weight of the WDH.

If you are concerned about the total vertical load which will be imposed on the receiver,
the total load will be equal to tongue weight plus weight of the WDH minus the amount of load transferred to the TT's axles.

Since the amount transferred to the TT's axles almost always is greater than the weight of the WDH,
the total vertical load imposed on the receiver almost always will be less than the tongue weight.

Ron

The Ford towing guide shows two hitch weight ratings: with and without WDH. The rating with the WDH is exactly 10% of towing capacity for the 2014 trucks. I suspect that Ford calculates the max hitch load based on the vehicle's suspension, etc., and then multiplies by 10 to get the max tow weight.

Ron Gratz wrote:
I see nothing in the above numbers to suggest why there is a 500# difference in maximum allowable tongue weight. Ron

I don't either. I'm still working on getting a contact at the Flint, Michigan plant where they build the HD trucks.

For the 2013 2500HD and 3500HD --
rear overhang for standard box is 47.6"
and rear overhang for long box is 52.5".

Combinations of Wheelbase and Rear Overhang are listed below along with the tongue weight required to add a load of 1400# to rear axle when no WD is applied.

Column 1) Wheelbase
Column 2) Rear Overhang
Column 3) Tongue weight required to add 1400# to rear axle assuming Ball Overhang is equal to Rear Overhang plus 10".

133.7" 52.5" 954# 4x4 Regular Cab Long Box
144.2" 47.6" 1001# 4x4 Extended Cab Standard Box
158.2" 52.5" 1004# 4x4 Extended Cab Long Box
153.7" 47.6" 1018# 4x4 Crew Cab Standard Box
167.7" 52.5" 1020# 4x4 Crew Cab Long Box

I see nothing in the above numbers to suggest why there is a 500# difference in maximum allowable tongue weight.

Ron

waynec1957 wrote:


What we’re talking about here is 14” difference in wheelbase between a standard box (6’6”) and a long box (8’). Not only that, but according to the manual a 2500 hd with a long box also has a 500 lb higher TW rating than a 3500 hd with the standard box. Doesn’t make any sense at all…

There has to be something I'm missing here. When I get some time I’ll see what I can find out.

Do long bed and short bed have different rear overhang - distance from rear axle to hitch? If the long bed has a shorter distance, that's less leverage from the hitch on the rear axle.

Crespro wrote:

Ron Gratz wrote:

Crespro wrote:
The sales manager makes this argument -- the regular hitch rating is 600#. With 1,100#, the Equalizer moves 200# to the trailer and 300# to the front wheels, leaving the spec 600# on the receiver. The Ford is 895 WD and 600# regular hitch.

I was not popular when I pointed out this problem. What do you think?

I would say the sales manager either is unaware of the facts or is intentionally misrepresenting the facts.

With a wheelbase of 119" and a ball overhang of 65", 1100# of TW would cause about 600# to be removed from the front axle and about 1700# would be added to the rear axle.

Assuming the distance from coupler to midpoint between the TT's axles is 240", restoring the 600# which was removed from the front axle would require about 600*119/(65+240) = 234# to be transferred to the TT's axles (at least, the sales manager was close on that guess).
The added load on the rear axle would be reduced to 1700-(600+234) = 866# -- probably enough to cause the rear GAWR to be exceeded.

The remaining load on the receiver would be 1100-234 = 866# -- which is not very close to the sales manager's 600#.

Furthermore, the receiver's rating is based on the TT's tongue weight and not on the vertical load on the receiver.

I think I'd be looking for a different place to buy a trailer.

Ron

Thanks very much. We are looking for another trailer that meets all of the specs.

I’ve dug into this issue a little. I spoke with a quality service rep from the Ft. Wayne truck plant (which produces ½ ton trucks, not 2500hd or 3500hd) and the preliminary answer I’ve gotten is the reason a 2500hd/3500hd standard bed (6’6”) truck is rated 500 lbs. less tongue weight than a 2500hd/3500hd long bed (8’) truck with the same hitch has to do with the difference in wheelbase. When I pressed him, he couldn’t tell me WHY 14” difference in wheelbase equated to 500 lbs. difference in TW rating, so I’m working on getting in touch with someone from the Flint Michigan assembly plant where they produce heavy duty trucks.

I’ve also been in touch with Terry from Hensley Manufacturing and he gave me some interesting information regarding tongue weight (I’m also going to contact Sean at ProPride).

Terry tells me there are two different issues in regard to tongue weight. The first is the TW weight designed into the trailer by the manufacturer which is 10% to 15% of the total weight of the trailer, but in recent years has gotten to be more like 10% to 12% to make trailers “half ton towable”. I checked the numbers listed by the factory on the TT we’re leaning towards and what they advertise works out to roughly 13% so he’s probably pretty close on this.

The second issue he talked about is the TW recommended by sway control hitch manufacturers which is closer to what we’ve been talking about here—12% to 15%. The reason for this, according to Terry (and he’s probably right on this too) is 12% to 15% is what is required for the sway control hitches to function properly. In other words, tongue weight is part of the friction that helps control sway on “conventional” sway control hitches.

What was interesting is what he said about TW and the Hensley Arrow (and presumably the ProPride 3p hitch since they both function basically the same).

“The Hensley Hitch is not a sway control hitch. We are not interested in trying to control trailer sway, or to regain control of a trailer that has already begun to sway. The Hensley Hitch does not use tongue weight in any manner to gain stability in a trailer. No matter how much tongue weight or little tongue weight you have it will always be impossible for your trailer to sway or fishtail when you pull with a Hensley. “

If what he says is true (and I have no reason at this point to believe it’s not based on how the hitch works), then when loading a TT using a Hensley (or presumably the ProPride 3 P) one could adjust the tongue weight closer to the manufacturer’s specs—which could make a big difference.

For example, the TT we’re considering has a GWR of 10,300 lbs. Say we (hypothetically) load it to 10,000 lbs. Using the recommended numbers for a sway control hitch (13% to 15%) splitting the difference at 14%, I should have a tongue weight of 1,400 lbs. which puts me right at the limits of most to the sway control hitches out there.

Now…if I load the same trailer to the same weight using a Hensley (or presumably the ProPride 3 P), if I load it to the manufacture’s TW specs (in the above case 13%) I’m at 1,300 lbs with a 100 lb. cushion. By the way, as a side note, according to Terry you DO NOT have to add the weight of the Hensley into the TW equation.

I had sort of had these “premium” hitches in the back of my mind since we’re looking at a much bigger TT, but this has made me want to take a closer look at them.

queenie2 wrote:
I have a solution for this issue. Load everything up to traveling loads, adjust the WD bars so that the rig is level, particularly the TV, and weight each axle seperately.---

What do you mean by "the rig is level"? If you're saying there should be "equal squat" front and rear, that does not agree with Ford's specification for adjusting a WDH.

---The next step is compare each axle weight do determine that the tires and the individual axles are not over loaded per the manufacturer's specs.---

That's good to do, but I believe the "issue" is keeping the TT's tongue weight under the receiver's maximum tongue weight rating.

---The load distribution details of the total rig and the published highway spec are way too complicated to reach any conclusions on a forum.

Can you explain this statement? What do you mean by "distribution details of the total rig"? What do you mean by "published highway spec"?

Ron

I have a solution for this issue. Load everything up to traveling loads, adjust the WD bars so that the rig is level, particularly the TV, and weight each axle seperately. The next step is compare each axle weight do determine that the tires and the individual axles are not over loaded per the manufacturer's specs. Keep track of all of the components involved by close inspections concentrating on wear items and structural cracks before each trip. Enjoy your new RV. The load distribution details of the total rig and the published highway spec are way too complicated to reach any conclusions on a forum.

Ron Gratz wrote:

Crespro wrote:
The sales manager makes this argument -- the regular hitch rating is 600#. With 1,100#, the Equalizer moves 200# to the trailer and 300# to the front wheels, leaving the spec 600# on the receiver. The Ford is 895 WD and 600# regular hitch.

I was not popular when I pointed out this problem. What do you think?

I would say the sales manager either is unaware of the facts or is intentionally misrepresenting the facts.

With a wheelbase of 119" and a ball overhang of 65", 1100# of TW would cause about 600# to be removed from the front axle and about 1700# would be added to the rear axle.

Assuming the distance from coupler to midpoint between the TT's axles is 240", restoring the 600# which was removed from the front axle would require about 600*119/(65+240) = 234# to be transferred to the TT's axles (at least, the sales manager was close on that guess).
The added load on the rear axle would be reduced to 1700-(600+234) = 866# -- probably enough to cause the rear GAWR to be exceeded.

The remaining load on the receiver would be 1100-234 = 866# -- which is not very close to the sales manager's 600#.

Furthermore, the receiver's rating is based on the TT's tongue weight and not on the vertical load on the receiver.

I think I'd be looking for a different place to buy a trailer.

Ron

Thanks very much. We are looking for another trailer that meets all of the specs.

Ron Gratz wrote:
I'm hoping some 2500HD/3500HD owner will ask Chevrolet why the long bed truck can handle 2000# TW while the short bed truck only can handle 1500#.
I would love to hear the "official" answer.

The wheelbase could explain a 10% difference, but I can't see any logical explanation for a 33% difference.

Something else that's confusing about this in the manual is, it says for 2500 and 3500 trucks towing trailers up to 18,000 lbs using a WDH is optional.

It also seems to defy logic that maximum allowable TW does not depend on WD or no WD -- while maximum allowable trailer weight does.

Perhaps we shouldn't be trying to apply logic? :h

Ron

What we’re talking about here is 14” difference in wheelbase between a standard box (6’6”) and a long box (8’). Not only that, but according to the manual a 2500 hd with a long box also has a 500 lb higher TW rating than a 3500 hd with the standard box. Doesn’t make any sense at all…

There has to be something I'm missing here. When I get some time I’ll see what I can find out.