How to use a CAT scale for RV and truck towing?

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Fasttimes

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I've never used a CAT scale, but would like to get real world numbers for my Expy/trailer set up. What is the procedure? Cost? Do it once, or more than once with WDH loaded/unloaded? Any way to weigh hitch weight there?
 

mwl001

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I've only checked empty vehicle or loaded with WDH engaged. Probably the most useful numbers are with WD engaged and unengaged to make sure that's working properly. If you want tongue weight you would just unhook your trailer and leave the tongue jack on it's own pad, the rear axle(s) of the trailer on another pad. You typically want your front axle on a pad, rear axle on a pad, and trailer axles on a 3rd pad (I believe there are 4).

SUVs are trickier to "balance" with weight distribution than pickups because they're closer to a 50/50 distribution, so you have less extra capacity on the rear axle and also on the front (since your goal is to shift more than on a pickup). In other words its tougher to return the vehicle to what feels like "normal" handling. But 700lbs or less tongue weight I don't think is difficult at all with these when using weight distribution.

$12 for first weigh, additional ones are only $2-3 if you "reweigh" in the same "session".

There's an app to make it easier, "Weigh My Truck" in iOS not sure what it would be in Google.
 

MHay

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All good info from @mwl001. There are three pads. You’ll want to do three passes - one fully hooked up with the WDH, one with the WDH bars unhooked, and a third separated from the trailer. For the first two you’ll have the trailer axles on one pad and the TV axles on their own pads. For the third pass you’ll have the TV on its own pad, the trailer axles on a pad, and the trailer jack on the third pad.
 

shane_th_ee

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You don’t need to weigh the trailer at all on the third pass. Just the truck. Here’s what you’ll do for math:
Trailer weight: gross weight of first weigh minus gross weight of just the truck (3rd weigh).
Tongue weight: sum the weights of the steering axle and the drive axle from the second weigh (WDH bars disconnected) and then subtract the weight of the truck alone (third weigh).
You can now divide the tongue weight by the trailer weight, multiply by 100 and have your tongue weight as a percentage of your trailer weight.

Next, you’ll want to find how much weight the trailer takes off the front axle without the WDH bars connected: subtract the 2nd weigh’s steer axle weight from the 3rd weigh’s steer axle weight.

Next, you’ll calculate how much weight your hitch is distributing back to the steer axle. Subtract the first weigh’s steer axle weight from the second weigh’s steer axle weight. This number should be between 1/3 and 1/4 of your tongue weight. This number should also be at least half of the weight the trailer takes off the steer axle (see number in the previous calculation).
 
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Fasttimes

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Was able to hit the scale this weekend on the way to a trip. I did 3 passes, TV - trailer WDH connected, TV/Trailer WDH arms unloaded, and TV on one scale and trailer with jack on middle scale alone and trailer axles on rear.

The numbers were very surprising and not in a good way. I will add this trip was my "MAX" trip when I take 3 teenage boys on Spring Break and just I. I may have this kind of load 2-3 times tops.

Here are the numbers.

2010 Ford Expedition Eddie Bauer with HD tow. 10,000# Equalizer WDH, 2015 27RBDS Winnebago Ultralite

Truck sticker has payload of 1402, FGVWR of 3700 and RGVWR of 4250
Trailer has two 3500 axles, and an GVWR of 7700

First Pass, car loaded with passengers, one very small cooler. WDH engaged.

Steer Axle: 3020

Drive Axle: 4520

Trailer Axle: 6800

Gross Weight: 14340


Second Pass, car loaded with passengers, one very small cooler, WDH arms unloaded

Steer Axle: 2520

Drive Axle: 5220

Trailer Axle: 6600

Gross Weight: 14340



Third Pass, car loaded with passengers, one very small cooler. Car completely on pad 1 of scale, Trailer Jack on middle pad, Trailer axles on rear scalse

Steer Axle: 6640

Drive Axle: 1100

Trailer Axle: 6580

Gross Weight: 14340


So if I'm reading this correctly I'm running a hitch weight of 1100lbs. Which is way more than I thought. I was thinking in the 800lb range. I did just last week buy one of those Sherline Weight scales and weighed right as we left my driveway. It indicated 950lbs, so not sure who's the more accurate.

Payload I knew off the bat I was over, but the 270lbs over on the rear axles is quite concerning. I do know I should have added my last washer on the WDH hitch with the added weight of the passengers, so for sure I would have maybe off-set some of the rear weight towards the front axle which was probably running a bit light. But not sure if I can make up the 270lbs of over capacity on that rear axle with just doing that. I know I can move around some of the cargo in the forward hatch, but honestly I'm not really loaded up with much to begin with in that cargo hold. But I can move some stuff to the rear bathroom cabinets I imagine to help out.

So, this brings me to my current dilemma where to go from here. 80 % of trips it's just myself, wife and dog and probably just at or very slightly above that 1402 payload capacity. But I'm not liking being at the limits all the time, especially with an older truck running 145k miles. I was intending to upgrade to a like-new 4th gen Expy soon but even then I fear I'm still going to be right at the limits most the time. I guess I could look at the XLT Max models of the Expys to get max payload but it wouldn't be my choice if I have to, wife does like the bells and whistles of the upper trim models.

So I'm considering moving up to a Diesel F250/2500 class pickup but the idea of this isn't sitting well with the wife and do I want to spend that kind of money on a truck I use 6 times a year for towing? I'd probably then need to buy a 3rd vehicle for a daily driver since I don't necessarily need to drive a tank to work every day. Ok, I"m making my head hurt just thinking about this. ;-)

Open to all opinions and suggestions.
 

JasonH

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You're at the limit for towing with this vehicle. Your tongue weight should be 768 - 1,1582, using 10 - 15% guidelines. Even 12.5% (968lbs) puts you slightly above the rating for the vehicle. Since this seems to be a trailer weight issue, your options are getting a lighter trailer, or getting a different tow vehicle. A properly configured half-ton truck should handle this load. I don't think you need the diesel over an Ecoboost unless you're doing gobs of miles, as the fuel, maintenance, and price premium won't be recovered in a short duration. The half-ton pickups are lighter and may have more payload depending on trim. Assuming the adjustments below don't bring you within the proper weight distribution, you'll have the same issues with a newer Expedition.

In the meantime, you can make things better by moving adjusting your ball height (within manufacturers specifications), moving your battery off the tongue, not using the front storage, and traveling with empty propane, assuming they're in the front as they normally are. Tongue weight varies by manufacturer, so there's no guarantee that any of these will address your issue. Your WDH is also not configured properly, as it should be able to push substantially more weight to the front axle. You didn't specify which type you're using, but since it takes washers to adjust the head angle, I would max out the number you use (in line manufacturers specifications). The brackets on the trailer frame should be the max distance specified in the manual from the ball receiver, and adjust the brackets so they push the arms higher. This should restore more weight to your front axle.
 
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Fasttimes

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Guess I figured with the Expy being on the F150 platform that the payload capacities would be near the same. Guess could look at that option.

The hitch is an Equalizer 10,000# set up. I think I have the max distance I could extend the arm brackets. Regarding adding the 8th washer, I did that not too long ago on a trip with just the wife, dog, and I and it became "loose" on the highway. I felt that it had lifted too much weight off the rear axle so I removed it. But this last trip was much more weight in passengers and definitely could have used that last washer.
 

mwl001

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You want to max out your Equalizer so that once it's engaged (with the maximum angle on the bars) your trailer returns to level or slightly nose down. The "looseness" might be from having the trailer lower at the back than the front - this was our issue early on but having the proper drop shank fixed it - we needed quite a bit of drop for our trailer. Past that I think the best option is to lighten what you take - hopefully your water tank is empty and you may have to leave a lot of heavy stuff at home since it sounds like you need cargo for passengers.
 
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Fasttimes

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Looks like an F150 wont fit the bill from what I can see. Even though they have higher tow ratings, they're payload is pretty much the same as Expys. Got all excited when I saw some F150 people talking about a Heavy Duty Payload Package and 2200lb payloads, but turns out it's near impossible to get that short of fleet vehicles with no options.
 

JasonH

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Looks like an F150 wont fit the bill from what I can see. Even though they have higher tow ratings, they're payload is pretty much the same as Expys. Got all excited when I saw some F150 people talking about a Heavy Duty Payload Package and 2200lb payloads, but turns out it's near impossible to get that short of fleet vehicles with no options.

You're correct. The F150 isn't substantially higher (excluding the HDPP unicorn). But if you can get nearer 1800lbs, you'll be closer to making weight. It's either that, an F250, or a lightweight trailer. There are some nicer trims that are near that. There are some photos on the F150 forums of payloads for different trim levels. As you're already aware, the higher the trim, the less payload.
 
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