Definition of Tongue Weight

[tommy_z]

I recently had my rig weighed, and it showed 1080# of tongue weight.

Connecting the weight distribution moved some rear axle weight to the front axle, and some to the trailer axles.

Does that mean some of the tongue weight moved too? If so, how do I determine how much?

Or can tongue weight only be reduced by physically moving/removing mass?

[chuckster57]

Your tongue weight will not change when you hooked up the W/D. It's call weight distribution because it distributes the tongue weight.

Only way to physically change the tongue weight is doing like you asked. Moving cargo/mass.

[tommy_z]

My TW weighed out to 1080#. My receiver rating is 930#.

If weight distribution transfers the tongue weight, is there a way to find out if I'm at/under the rating?

[sourdough]

What kind of receiver? Class IV, V? Do your specs give you weights for WD vs non WD? Seems like 930# is an odd number for a hitch rating.

[chuckster57]

I'm not sure what the formula for figuring that out is, sorry math wasn't my favorite subject.

There should be 2 ratings on the hitch
1) weight carrying. I assume that means no W/D just the weight of the tongue

2) weight distributing. I think that's the max weight before the W/D bars are added.

I will freely admit that I am not an expert on W/D. I have towed 5er since '89 and only recently started gaining experience and knowledge about W/D. When I see W/D and sway added to a "get ready", I check the GVWR of the trailer and install the set rated for that. Hopefully someone that knows the math can teach us both!!

[GMcKenzie]

Weigh all the axles of the truck with no trailer hooked up.
Then weigh just the tongue of the trailer. This will be the tongue weight.
Then hook up, but don't put on the WD bars. Weigh the truck axles again. The increase is going to be about the same as the tongue weight you weighed.
Weigh the trailer axles as well.
Then hook up the WD bars and weigh everything again. The truck should weigh less than in the prior step, and the trailer weigh more. So while the tongue weight doesn't change, the bars allow for some of the TW to be transferred (distributed) to the trailer axles.

Nice to do at a free scale with no trucks waiting around. I did all this at one weigh scale that was closed. Had a guy in his semi stop and just watch me. But it takes a 1/2 hour or so between all the unhooking, hooking up, unhooking again, hooking up again and moving back and forth.

[CWSWine]

I have only owned on TT so not real experience with WD setup. What i did learn is if you have 1000 lbs of hitch weight you can shift weight forward to the TV front axle and aft to the TT axles and reduce tongue weight by a XX pounds. The weight is still there but shifted forward and aft.

The way tell what you tongue weight is to weigh the truck without the TT and then weight the truck with the TT and WD hooked up and subtract the difference in the rear wheels weights. If you want to know how much weigh has shifted you need to weight the truck and TT without the WD hooked up.

Hope that helps...

Here is good site to do the math for you http://www.towingplanner.com/

[theeyres]

As Chuckster57 says, weight distribution does no change tongue weight. End of story. Your tongue weight is so little over I wouldn't worry about it, but that is only my tendency to not be concerned about things like that. But tongue weight is tongue weight. Weight distribution doesn't change it...it only moves the weight from the rear axle of the truck to the front axle. Think of a teeter totter. If you weight 150# and sit on one end, you can slide the fulcrum back and forth to get a better balance but you are still putting 150# on your end. The process of tilting the trailer slightly more towards the rear may take a miniscule amount of weight off the hitch but not enough to be concerned about.

[slow]

As others have stated, for the purpose of deciding if you are over capacity on your receiver, the tongue weight does not change when applying a WD system. A TV receiver will have two ratings, one (lower) rating without WD and a second (higher) rating with WD. The 930 lb rating sounds like it is the higher capacity with a WD system. I am guessing the lower rating without WD for your receiver is no more than 500 lbs. The difference in ratings for with and without WD reflects what the receiver manufacturer has already factored in to account for the load distribution resulting from the use of a WD system. So the fact is that you are 150 lbs over the capacity of your receiver with WD.

If you have concerns with this situation, there may be an aftermarket receiver for your vehicle with a higher capacity. They are relatively inexpensive ($150 to $200) for the peace of mind it may bring you.

eTrailer is one of the sources I have used in the past to upgrade my OEM receiver to a higher rating. U Haul is another source if you are not a DIYer.

As you speculated, the way to reduce tongue weight is to remove weight from the TT that is forward of the TT axles and moving the weight to behind the TT axles. The further forward and behind the TT axles the weight is, the greater the affect the movement, addition or removal of the weight will have on tongue weight. Depending on your floor plan, it can become difficult to move weight to the rear of the TT since the largest storage area is usually at the front of the TT under the bed. Another consideration is that you do not want your tongue weight to reduce below 10% of your loaded trailer weight. If you do, you increase the likelihood of sway. BTW: many target 12 to 13%, not the minimum of 10% and maximum of 15%.

Suggestion: Since you know your tongue weight, do you also know your loaded TT weight? If so, multiply your loaded TT weight by 0.1. If the resulting number is less than 930 lbs, it means you have a chance of redistributing the cargo in your trailer from the front to the rear and keep the tongue weight within spec while still achieving the minimum 10% tongue weight. If the calculated number is more than 930 lbs, a new receiver will give you peace of mind.

[CWSWine]

Is this or isn't shifting weight and lower the pin weight on the TV.

Here is a real world weights of TT

1st weigh fully loaded and WD hitched
Steer axle 4340
Drive axle 4500
Trailer axle 4900
Gross 13740

2nd weigh wdh off
Steer axle 4180
Drive axle 4760
Trailer axle 4840

3rd weigh only TV
Steer axle 4320
Drive alex 3400
Gross 7720

You can subtract the TV Weight Drive Axles of 3400 from First set Drive Axles numbers 4500 gives a tongue weight of 1000lbs with WD.

You can subtract the TV Drive Axles of 3400 minus the second set of numbers Drive Axles 4760 give you 1360 tongue weight without WD.

All the weight is still there just shifted forward and aft axles.

[slow]

Sure the WD shifts weight. No debate.

But the point I am trying to make is that the receivers are rated with WD for a tongue weight prior to applying the WD.

So if you have a tongue weight w/o WD of 1080 and a receiver rated for 930, you are exceeding the receiver rating no matter how much weight you shift to the TT and rear TV axles once the WD is applied.

[CWSWine]

Originally Posted by slow

Sure the WD shifts weight. No debate.

But the point I am trying to make is that the receivers are rated with WD for a tongue weight prior to applying the WD.

So if you have a tongue weight w/o WD of 1080 and a receiver rated for 930, you are exceeding the receiver rating no matter how much weight you shift to the TT and rear TV axles once the WD is applied.

I just called out local hitch place and he said that was after the WD was installed not before. I'm not sure but I was told after also WD was installed. I have only owned one TT before I went to 5er so not up on all the ins and outs of WD hitches.

[JRTJH]

Slow is correct (the way I understand WD hitches). Before the hitch can "redistribute" any weight, it has to have the weight applied. Then, through leverage, it shifts that weight forward or aft. But, the entire weight, regardless of any "distribution" is still applied to the hitch, only it appears to be "leveraged" to another location. The total weight of the trailer tongue is still resting on the receiver ball, some is "pulled by levers" to the rear and some is "pushed by the leverage" to the front.

[slow]

Please note that I am referring to ratings of the receiver and what the conditions are when determining if you are within the ratings. That is different than discussing what a WD does.

Your hitch place is talking about the load on the ball after applying the WD by loading the bars. And I agree that the load on the ball decreases when the WD is applied by loading the bars. An engineering load diagram would demonstrate that, but it has been a few years since I did one. What the WD does is create a "moment" in engineering terms (same as torque) thereby loading the trailer axles and TV front axle while unloading the ball and TV rear axle.

So everyone is correct, but we are talking about different aspects of the tongue weight.

Bottom line is that the OP can move cargo weight behind the TT axle from in front until he pushes the 10% ratio. Or install a higher rated receiver for peace of mind.

Sent from my iPhone using Tapatalk

[tommy_z]

Thanks all. You have answered my question.

I have learned so much about safe towing from this site, I greatly appreciate that.

I like the suggestion of replacing the receiver with a higher rated one. Unfortunately I can't find such a thing for my TV. Looks like I just got a step closer to a new truck.