So, I think I am good, weight wise.

[Jerry Burks]

I spent some time today, weighing each axle separately of our rig (with a modified cattle scale). This is an Alliance Paradigm 310RL 5th wheel, towed by a 2021 F350 SRW Diesel.

F350 specs:
Front FAWR 5200, RAWR 6780, GVWR 11500, Payload 4420

Trailer specs:
Dry 12275, GVWR 15000, Hitch 2530, Axle rating 7000, Tire Rating 4410 each

Actual weights:

F350 alone (w/hitch in bed), full diesel tank, no driver:
Front 4160, Rear 3381

Hitched on Trailer, 70 gal fresh water, black and grey tanks empty, with Onan generator and full propane bottles:

F350:
Front 3930, Rear 5560

Trailer itself:
Rear Axle 4816, Front Axle 5816

Looks alright to me, even with some reserve when the black/grey tanks are full (adding about 800 lbs, mostly over the trailer axles).

The hitch weight calculates to approx. 2200 lbs or 17% of the total actual trailer weight.
That leaves me 2200 lbs payload and about 900 lbs rear axle weight reserve.

I am not sure though why the front and rear trailer axles have almost a 1000 lbs weight difference. I thought the suspension is supposed to equalize that.

Another question is why the truck front axle is a little bit lighter when hitched up. Maybe it was the slight incline with the trailer pulling backward.

Anyway, here are the numbers. Any opinion?
Although a 1-ton SRW is frequently mentioned to be borderline for a 15000 GVWR 5th wheel, it looks like ther is still some reserve. Or maybe the trailer specs are a bit conservative...

[xc-mark]

Yes your rear axle weight on the truck is good and safe. Its odd to me that the truck weight with the trailer hooked up is less then the truck empty , was this all done the same day and same amount of fuel on board? I guess if the rear of the truck sits low maybe the fuel is in the back of the tank . Typical a 5th puts about 100 lbs on the front axle and most of the weight on the rear for pin weight because the pin is typically located 4" forward of the center of the axle.

Good choice to get a one ton , a 3/4 ton would have been almost max on the rear end.

[Old-Biscuit]

F350 alone (w/hitch in bed), full diesel tank, no driver:
Front 4160, Rear 3381
Total----7541

F350: (trailer hitched up)
Front 3930, Rear 5560
Total----9490

9490 - 7541 = 1949
Less then DRY weight
????

1000# difference between front & rear trailer axles (front heavier)
?????

Typically trailer axles will be close OR rear heavier if Nose High

Pin weight is Very Light

Suspect your scales are a bit off
?????

[Jerry Burks]

Originally Posted by Old-Biscuit

........Suspect your scales are a bit off?????

Entirely possible. This is not a professionally calibrated CAT scale. But the error should be small. I weigh myself around the correct 184 pounds before and after weighing the trailer/truck and the zero does change only 1 or 2 pounds. Also, these load cells (4 x 5000 lbs capacity) are usually quite linear.

I believe most of the discepancy comes from weighing the rig on my slightly inclined (about 3 degrees) driveway. I made a quick calculation and found, given the trailer weight, the incline will tug the truck backward with about 670 pounds force (parking brake set). The hitch pin being 50" above ground and with 160" wheel base that will cause a 210 lbs weight transfer from the front to the rear axle. So the corrected truck weights on level ground with trailer attached would be:
Front 4140 lbs, Rear 5350
which means essentially front is unchanged and rear loaded up 2000 lbs pin weight. The latter still still looks relatively low to me but maybe that is what it is. I will try that again sometimes on level ground or compare it to a CAT scale reading.

[Old-Biscuit]

Trailer specs:
Dry 12275, GVWR 15000, Hitch 2530, Axle rating 7000, Tire Rating 4410 each

Per specs the DRY pin weight is 2530 based on DRY trailer weight of 12,275

YOUR scale weights only show 2000# pin weight
????????

Really need to go to CAT Scales and get 2 weigh tickets
One...truck/trailer
Then drop Trailer in parking lot and go reweigh truck

THEN you will have ACTUAL weights

[JDT]

I am not sure about your weights being accurate. I took my long bed with a full 48 gallons of fuel, me in it, a bed cover and a few tools under the back seat. No hitch as we have a Reese Goose Box. My front axle weight was 5140 and the rear was 3620, 8760 total. The extra 14 gallons in my truck over your 34 gallon tank account for about a 100 pounds but that would still leave about an 1100 pound difference. I have a Platinum but ordered it without a sun roof or the FX4 package to cut some weight.

I would think our front weights would be similar but you are showing almost a thousand pounds less. That doesn't sound right unless the scale I used at a QT truck stop was off.

Our Pinnacle, which is similarly sized to yours, had a 2445 brochure listed dry hitch weight. We did add a Splendide washer/dryer which sits in the front closet so I knew the hitch weight would increase. Also, the Goose Box is about a 100 pounds heavier than the original pin. I weighed at the same scales, fully loaded for a month long trip to the Rockies, and my hitch weight is 3120. I know each fifth wheel is different but your pin weight sounds a little light.

My original yellow sticker payload was 4562. My truck was one of the 12,400 GVWR trucks that had a recall because Ford miscalculated the payload. I just got a new sticker and it is now 4054. I had a really nice cushion with the previous payload but while I'm still not over the new figure I don't have very much of a cushion. I am waiting to see what Ford does about it as some folks who were towing within limits are now over their payload and not happy.

[Jerry Burks]

Now you guys got me curious. I will take it to a CAT scale for comparison.

[BirchyBoy]

Originally Posted by Jerry Burks

Now you guys got me curious. I will take it to a CAT scale for comparison.

It has been a while. Did you get your weights? We’re looking at a 310RL and I’m curious where you ended up.

[Jerry Burks]

Not yet, sorry...
I am going to pick up the camper Tuesday 8/10 from storage to prepare for a longer trip. At that time I am planning to go to a CAT scale and report the results.

[Jerry Burks]

I did go to the CAT scale today and got following results.

Condition truck:
no driver or passenger, full diesel tank, 235 lbs hitch in place, 51 lbs tool box installed, ~60 lbs of tools and accessories, 30 lbs truck bed cover installed. Stromberg notched plastic tailgate instead of stock aluminum one.

Condition trailer:
Onan5500 generator, 2 solar panels and inverter, 300Ah Lithium, 2 full propane bottles, ~80 gal fresh water, empty black and grey water, fully loaded storage (2 folding e-bikes, grill, griddle, chairs/table, propane cooktop, cable spool etc.)

- Loaded rear axle is 6640 lbs, unloaded 3560lbs, i.e. pin weight is 3080 lbs
- Trailer axles are 11080 lbs, i.e. total trailer weight 14160 lbs (GVWR 15000lbs)

Additional while traveling:
330 lbs driver&passenger with 2:1 ratio front/rear adds 110 lbs rear
110 lbs dogs with 1:1 ratio front/rear adds 55 lbs rear
50 lbs clothing in the trailer goes full on the pin
other heavy items will be stored above or behind the trailer axles

--> total rear axle traveling weight approx. 6855 lbs.
That means I am right at or slightly above the edge of the door sticker RAWR of 6780 lbs (not the Ford RAWR catalog spec of 7230 lbs for this model).

I am not exactly sure where the black/grey tanks are located, so that may add another load but we usually empty them before travel.

[JHinman]

What is the configuration of your truck? You note F350, but is it crew cab, or Supercab? Short box or long box? 2WD or 4wd?

I just ask to compare your numbers to mine, out of curiosity.

I have 2018 F350 Limited, diesel, 4x4, crew cab, long box, 11,500-lb GVWR, and F4X package. Truck came with 20” all-season tires.

Curb weight is about 8,700 lb, with two people, fuel, tool box, bed liner, and receiver hitch.

A big difference is the rear axle capacity. My capacities are Front GAWR = 5,600 lb, and Rear GAWR = 7,230 lb. I am surprised the axle capacities are different for different configurations.

Capacities are from my door sticker.

[Jerry Burks]

Originally Posted by JHinman

What is the configuration of your truck? .....

This is a 2021 F350 Lariat, short bed, diesel, 4x4, crew cab

As mentioned, the web catalog lists 7230 lbs as RAWR spec while the door sticker is only 6780. But especially given the rear axle recall I rather use the sticker number.

[BirchyBoy]

Thanks for posting the numbers. I’m glad that the pin was just over 3k with the generator. Mine won’t have one, so hopefully it will be 2,800 or so. My truck has the same 6,780 RAWR with a CC of 3,900.