Tongue Weight

Steve's 70-5 · 05-03-2020, 02:59 PM

Trying to figure the tongue weight of my TT. On my way back from a trip this weekend, I stopped by a CAT scale and weighted everything. The first trip thru the scale, weighted truck and trailer, got weight of steer axle, drive axle and trailer axle. Dropped trailer and weighted truck only. With these weights can I figure tongue weight? What is equation to figure tongue weight.

xrated · 05-03-2020, 03:14 PM

You didn't say whether or not you are using a Weight Distribution hitch or not, but assuming you are, you need to do three weights.

1. Truck only, with all passengers, luggage, fuel etc. that you would normally carry when camping.
2. Truck (as described in number one) with the trailer hooked up and the W.D. bars tightened to where they normally would be.
3. Leave the truck and trailer on the scale after number 2 weight and disconnect the W.D. hitch spring bars. You don't need to remove them from the truck/trailer, just take the tension off of them and get your third weigh.

This method will give you all the number you need as well as showing you how effective the W.D. hitch is doing it's distribution.

Steve's 70-5 · 05-03-2020, 03:23 PM

Got weight of truck only , loaded for a trip.

Got weight of truck and trailer with Weight Distributed set up for travel, loaded for trip.

Did not get weight of truck and trailer with Weight Distribution unhooked.

So I am SOL of finding tongue weight.

xrated · 05-03-2020, 06:57 PM

Quote:

Originally Posted by Steve's 70-5

Got weight of truck only loaded for a trip.

Got weight of truck and trailer with Weight Distributed set up for travel, loaded for trip.

Did not get weight of truck and trailer with Weight Distribution unhooked.

So I am SOL of finding tongue weight.

Basically, yes...you need all three that I listed above. I'm putting a link to a website that has a work sheet and all the info you need to do the number, once you get that third weight..... https://fifthwheelst.com/

When you click the link and the page opens, along the top of the page you need to go to the "4-Step Weight Safety Plan". There will be a drop down and you need to download and print out the "Worksheet". The next step shows you exactly where and how to weigh the truck/trailer combination that you have. Step 3 is inputting all the numbers that you have collected from your 3 weight scale tickets (so yes, you do need to do the 3 weights that I listed above). When you input all of those numbers and click the calculate button you should see exactly where you are tongue weight wise as well as other critical weight ratings and whether you are within them. One word of caution....make sure that you select the proper worksheet....the one for a tow behind trailer and not for a 5th Wheel trailer...as they normally on require two weights because they do not use W.D. hitches.

**flybouy** · 05-03-2020, 07:52 PM

Or you could purchase a Sherline scale and know exactly what it is before you leave. I use it for loading for extended trips (extra bottled water, etc.) so I know if I need to place more weight further back, especially if I'm towing with full water tank (it's in the front).
https://www.amazon.com/Sherline-LM-5.../dp/B007REJKXA

DocP · 05-04-2020, 12:43 AM

Quote:

Originally Posted by flybouy

Or you could purchase a Sherline scale and know exactly what it is before you leave. I use it for loading for extended trips (extra bottled water, etc.) so I know if I need to place more weight further back, especially if I'm towing with full water tank (it's in the front).
https://www.amazon.com/Sherline-LM-5.../dp/B007REJKXA

Yes. Have used one for the past 12 years, and it's one of the best tools I've got for the camper.

CedarCreekWoody · 05-04-2020, 03:48 AM

Yes, you can determine tongue weight with the two measurements you have. It is the difference in the truck weight on the two measurements. What you can't determine without the third measurement as described above is how effective your WDH is in transferring weight to the front axle of your truck. You should check that.

Steve's 70-5 · 05-04-2020, 05:37 AM

Here are the weight

Steer axle. 4720
Drive axle 4660
Trailer 5920

Truck only
Steer axle 4940
Drive axle 3460

I just need tongue weight. I think I do not have a heavy enough bar for my sway control. Manufacture wants tongue weight to tell me what I need.

A Sherline scale is probably in the future

**flybouy** · 05-04-2020, 06:28 AM

Steve, that Sherline scale is an analog dial gauge. Sorry, couldn't resist.

Keystoned · 05-04-2020, 07:06 AM

Looks like at least 1200 lb as weighed?

**flybouy** · 05-04-2020, 07:35 AM

Steer axle. 4720
Drive axle 4660
Trailer 5920

Truck only
Steer axle 4940
Drive axle 3460

4720 - 4940= -220
4660 - 3460 = 1200

1200 + (-200) = 1,000
Trailer tongue weight is ~17% of 5920

From what I get your front axle weight was reduced by 200 lb and you added 1,200 lb to rear axle when hitched. Are these numbers correct? Looks more like what I'd expect without WDH in use. The purpose of the WDH is to distribute the hitch weight across both truck axles.

If these numbers are correct then you should see front end lift (more room between fender and tire) and rear end squat (less room between fender and tire). Check the set up on the bars/hitch and follow the mfg instillation instructions.

Someone correct me if I'm incorrect or missing something.

Steve's 70-5 · 05-04-2020, 08:05 AM

Very good. I do like digital gauges.

**chuckster57** · 05-04-2020, 08:10 AM

Quote:

Originally Posted by flybouy

Or you could purchase a Sherline scale and know exactly what it is before you leave. I use it for loading for extended trips (extra bottled water, etc.) so I know if I need to place more weight further back, especially if I'm towing with full water tank (it's in the front).
https://www.amazon.com/Sherline-LM-5.../dp/B007REJKXA

I have both the 0-2000 for tt’s and the 0-5000 for fivers in my tool box. Many customers have had a surprise, and that’s without any cargo.

Keystoned · 05-04-2020, 08:12 AM

And that's why I shouldn't do math in public...lol

Steve's 70-5 · 05-04-2020, 08:13 AM

The bars I am using are rated for 750lbs. tongue weight. The trailer I am pulling has a rating of 750lbs. empty.

**flybouy** · 05-04-2020, 08:27 AM

Quote:

Originally Posted by Steve's 70-5

The bars I am using are rated for 750lbs. tongue weight. The trailer I am pulling has a rating of 750lbs. empty.

That "empty weight" was not valid once the transport driver put a battery in the battery box. The dealer installs the battery you get, the propane tanks and propane. All that weight is primarily on the tongue. Then EVERYTHING that you take in and leave in the trailer adds a percentage of it's weight to the tongue weight depending on where it is stored either fore or aft of the center of gravity. 750 lb bars are not sufficient for a 750 lb tongue weight (no margin left).

This why I like the scale I referenced. Without it you may hit the scales and uh oh, need to go home and reduce weight or redistribute it to get the proper tongue weight percentage. Instead of several trips to the scales it's a simple procedure. JMHO

Chuck, mine came with 2 gauges when I bought mine many years ago.

**flybouy** · 05-04-2020, 08:28 AM

Quote:

Originally Posted by Keystoned

And that's why I shouldn't do math in public...lol

You mean I got it right?

xrated · 05-04-2020, 08:53 AM

Quote:

Originally Posted by flybouy

You mean I got it right?

Not exactly.....the W.D. system is meant to distribute the tongue weight to the front axle of the truck and then back to the trailer axle(s). The hitch itself is the "pivot point", if you will. So the bars would be like attaching a lifting cable around the hitch and raising it. The result would be some weight moved to the front axle of the truck, and some weight moved to the axle(s) of the trailer. And, the amount of tongue weight never increases or decreased, it stays the same, but it causes some of the weight to go forward (truck front axle), and some to go rearward (trailer axle or axles)

**flybouy** · 05-04-2020, 09:01 AM

Quote:

Originally Posted by xrated

Not exactly.....the W.D. system is meant to distribute the tongue weight to the front axle of the truck and then back to the trailer axle(s). The hitch itself is the "pivot point", if you will. So the bars would be like attaching a lifting cable around the hitch and raising it. The result would be some weight moved to the front axle of the truck, and some weight moved to the axle(s) of the trailer. And, the amount of tongue weight never increases or decreased, it stays the same, but it causes some of the weight to go forward (truck front axle), and some to go rearward (trailer axle or axles)

Understand that but trying to point out to the poster how his numbers on the truck in relationship to the WDH, not the truck and the trailer. With a negative net on the front the WDH is not accomplishing the intended effect. Thanks for "filling in" the rest of the equation.

Frank G · 05-04-2020, 09:28 AM

Quote:

Originally Posted by Steve's 70-5

Here are the weight

I just need tongue weight. I think I do not have a heavy enough bar for my sway control. Manufacture wants tongue weight to tell me what I need.

A Sherline scale is probably in the future

It looks like you are trying to justify new (1000lb) bars. This is probably a justifiable purchase if it eases your mind. You might do some posting and see if anyone wants to trade. Is this a Blue Ox hitch? I was in this situation once.

Secondly, How does your unit tow as is? I would think near perfect as you have a totally capable tow unit for your camper. you are not even close to the edge and I doubt you will see much, if any, improvement going to 1000 lb bars or larger.

As always, just my opinion.

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