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Old 10-15-2017, 08:20 AM   #1
4 Rivet Member
 
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2017 26' Flying Cloud
Huntsville , Alabama
Join Date: Feb 2017
Posts: 288
CAT Confusion

This CAT scale weight confuses me.
Please help me understand.
Rig: 2017 F250 2017 26U:
Drive Axle F250 Only: 3380 lbs.
Drive Axle w/ 26U on the ball: 4780 lbs.

That's 1400 lbs!
I do not know the actual tongue weight of my 26U, but AS states around 900.
I know that on the ball the AS rode about 2 inches nose-low.
The AS is very lightly loaded, so that can't be it.
Would that nose-low account for several hundred pounds extra on drive axle?


However, I recently installed Equalizer and weighed yesterday.
Now I have:
- AS almost completely level with WDH engaged.
- Steer axle from 4780 to 4700 (pretty close to complete redistribution).
- Drive axle from 3620 to 4680 (1060 including hitch assembly).

With Equalizer I think this is now a good setup (correct me if I am wrong).
But the previous "on the ball" at 1400 lbs is really disturbing.

I towed this way "on the ball" for almost 2000 miles.
Should I be glad to be alive?
What am I missing?
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Old 10-15-2017, 08:42 AM   #2
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Frederica , Delaware
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Check out www.fifthwheelst.com they have a weighing worksheet you might find helpful.
My SOB has listed tw of 880 lbs. but ringings in at nearly 1200 lbs. This not so uncommon for manufacturers.
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Old 10-15-2017, 08:54 AM   #3
"Cloudsplitter"

 
2003 25' Classic
Houstatlantavegas , Malebolgia
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Thumbs up CAT weights.....

A minimum of three>>>

TV alone loaded for towing, (W/O boat)

TV & AS with no WD.

TV & AS with WD set. (you will probably need multiple runs)

Goal with a level rig>>>replacing unloaded frt axle weight within a reasonable limit, ours is 100lb. Not overloading frt & rear axle ratings & tire ratings w/proper inflation, staying under receiver weight limit.

An early example of a three weight run...with "camping" load

Bob
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Old 10-15-2017, 09:01 AM   #4
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2005 25' International CCD
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OP,
When I do the Equal-I-Zer set up the way they prescribe, following their recommended measurements at each corner of the truck with and without the WD bars, I'm happy with how it feels and weighs. Your weight on the steer axle looks high - is your F250 diesel? My steer/drive numbers are closer to 3,500/5,000 most of the time.

Getting enough weight transfer to the steer axle makes all the difference in giving my setup good feel to the steering and keeping the trailer steady on the road.
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Old 10-15-2017, 09:03 AM   #5
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2002 30' Classic S/O
Fleming Island , Florida
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Posts: 4,673
Quote:
Originally Posted by MWBishop View Post
This CAT scale weight confuses me.
Please help me understand.
Rig: 2017 F250 2017 26U:
Drive Axle F250 Only: 3380 lbs.
Drive Axle w/ 26U on the ball: 4780 lbs.

That's 1400 lbs!
I do not know the actual tongue weight of my 26U, but AS states around 900.
I know that on the ball the AS rode about 2 inches nose-low.
The AS is very lightly loaded, so that can't be it.
Would that nose-low account for several hundred pounds extra on drive axle?


However, I recently installed Equalizer and weighed yesterday.
Now I have:
- AS almost completely level with WDH engaged.
- Steer axle from 4780 to 4700 (pretty close to complete redistribution).
- Drive axle from 3620 to 4680 (1060 including hitch assembly).

With Equalizer I think this is now a good setup (correct me if I am wrong).
But the previous "on the ball" at 1400 lbs is really disturbing.

I towed this way "on the ball" for almost 2000 miles.
Should I be glad to be alive?
What am I missing?
What you are missing is that the drive axle was carrying both the tongue weight and the steer axle weight shifted off the front. It is not indicative of your tongue weight.

However, it is real weight on your hitch and drive axle. I would also say you might be lucky that you didn't break something or run off the road due to insufficient steer axle load.

Tongue weight will increase somewhat due to nose down, but the larger concern is the load on the front axle.

All of the above IMHO, YMMV.

Al
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Old 10-15-2017, 09:21 AM   #6
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Huntsville , Alabama
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Ahh:
"What you are missing is that the drive axle was carrying both the tongue weight and the steer axle weight shifted off the front. It is not indicative of your tongue weight."

Thanks - now it makes sense.

Yes, diesel.
On the ball only reduced steer axle from 4740 to 4500 so I did not think that was so bad. But as stated drive axle from 3380 to 4780 seemed like a lot.
However not level AS was very bad - glad to be alive.
Lesson learned - never believe dealership.

Now with Equalizer I have:
F250 Only:
Steer: 4780
Drive: 3620
Equalizer (10,000/1,000) fully engaged :
Steer: 4700
Drive: 4680

So redistributed Steer to near pre-AS and left 1060 on Drive - and level AS.
Isn't this pretty good?
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Old 10-15-2017, 09:25 AM   #7
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2003 25' Classic
Houstatlantavegas , Malebolgia
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Thumbs up

.....'Isn't this pretty good?'

Yes.

Bob
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Old 10-15-2017, 09:30 AM   #8
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2017 30' Classic
2022 Interstate 24X
Carlisle , Pennsylvania
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Hi

The receiver on the F-250 is rated for 1500 pounds. Even at 1,400 you were not straining that part of the system. You would have to dig a bit for the weight limit numbers on your specific rear axle.

Bob
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Old 10-15-2017, 09:42 AM   #9
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2017 26' Flying Cloud
Huntsville , Alabama
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My axles are rated for 6000/6300 lbs so that was really never an issue.

Yes, the F250 hitch is rated for 1500 lbs, but for the 2016 F250 I found this:
"If the provided 2.5" to 2.0" adapter is used, this reduces the Max. Trailer Capacity to 12,500 lbs. and the Max. Tongue Load to 1,250 lbs."

Since my ball hitch was only a 2 inch I did have to use the adapter. So I may have been getting close to its capacity.

Never the less, now really glad I installed the WDH. Should make the whole experience better and safer.

I'm still learning and I hope other newbies can make use of this info.

Oh, and I forgot another thing - I can now open the tailgate when hitched and that's really nice.
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Old 10-15-2017, 06:48 PM   #10
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Fort Worth , Texas
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As above, the three pass method adds detail. Cat Scale makes it easy.

Truck should always have max fuel, and TT with full fresh water and propane. Camping load plus passengers otherwise.

Set TV tire pressure to spec (Load & Pressure Table; but inside Ford guidelines). Test is running steady-state 1.5-hrs, and gliding to a stop in a rest or parking area. 5-7% pressure rise is ideal. 9-10% needs more air. Go up 5-psi with LT E-range tires.

Too many run with too much air. Braking and cornering suffer.

Same test for solo. But truck empty except for gear permanently aboard. These will be the lower end. The upper is not far above. One does not "tune" handling with tire pressure. Better shocks (Bilstein, KONI, Fox, etc) is a start on that.

I'm hardly alone in seeing above 100k miles on tires not yet at wear marks. Makes buying best tires easy. But ideal pressure is key.

Three-pass is a great reference tool for down the road a few years. Things loosen up, wear. Best to have full set of numbers.

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