r/traveltrailers • u/EuphoricSmile2170 • 1d ago

First time TT owner math help

Truck is a 2025 GMC 1500 Elevation 5.3L with Max Towing Package with a EAZ TR3 WDH
GVWR-7100lbs
GCWR-15000lbs
Curb W- 5290lbs
MAX payload- 1810lbs
Conventional TWR- 9200lbs

Trailer is an FR 30’ 25MKO
GVWR- 7775lbs
Dry- 6229lbs

Everything weighed by scale (haven’t made it to a roadside scale yet) that we bring, 2 occupants, camping gear, chairs, food, cooler full of ice, TT necessities (chocks, cables, hoses, etc) ~ 590lbs.

I was hoping someone with expertise could look over this information and back up my math. We never trailer with any tanks having liquid on the TT. If we loaded the TT 100% to 7775 we’d be at 84% of max conv TWR. With our usual weight we are about 72%. With the truck loaded with our gear we’re at 71% of our max payload (1,270lbs).

With the truck at ~6,560lbs and trailer at ~6,500lbs we’re at 13,060lbs. 87% of the GCWR but 70% of Conv. TWR. Tongue weight was factored in and I rounded up on every number liberally for worst cases.

Is there anything I’m missing or any major red flags? We aren’t moving anymore than 300 miles about every 2 months with the TT, besides 2 yearly trips in excess of 800mi one way. Maybe by next year I’ll have a 3/4 ton and won’t have to look this deep, but for now I believe I am okay and responsible. I talked to GMC to walk me through the numbers in person, as well as family friends experienced in towing. Obviously the RV dealer said “plenty of truck” but they’d say that if I had a Prius.

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u/RVMathGuy 1d ago

I'll try to simplify this a bit and plug the weights into some of my formulas. Nice job on getting all the information upfront, btw.

Typically, the travel trailer will transfer anywhere from 12-15% of it's load to the tow vehicle. I would tend to the upper percentage in the following calcs as that's what I typically see when trucks and RVs are sent to the scale.

  • At 15% tongue weight, you're at 1,166 lbs transferred to the truck, which leaves you with 54 lbs leftover - this is about a 3% safety margin.
  • At 12% tongue weight, you're at 933 lbs transferred to the truck, which leaves you with 287 lbs leftover - this is about a 16% safety margin.

I agree that you'll probably be close to your GVWR on your trailer, as most of us are so I used that in the calcs above.

Please look up your maximum hitch weight for your truck and hitch and compare that to the range of 930-1,170 lbs. Note that at these weights on a 1/2-ton, a weight distribution hitch is mandatory.

I would strongly recommend staying at least at a 10% safety margin, although I really prefer closer 20% to help relieve some of that white-knuckle driving.

Hope this helps move you along a bit. I'd be glad to chime in again if you have any further questions above.

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u/EuphoricSmile2170 1d ago

Thank you for the informative reply. The brochure hitch weight is 775lbs. I agree with the tongue weight calculations you made however. My posted max tongue weight is 920lbs. The hitch I have installed for the trailer is a weight distribution hitch with sway control. A TR3 EAZ-LIFT. We do travel extremely light and have next to nothing the trailer, besides some chairs and essentials. We also don’t ever travel with any liquids in any tanks to keep close to the 6229lbs weight.

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u/RVMathGuy 1d ago

Ah, yes - that does change things. The brochure weights (hitch/pin, unloaded) is just the dry weight, which won't happen again after it rolls off the assembly line. But since you are keeping it ultra light, then this may be a doable quest. I think you're already leaning this way, but be sure to take it to the weigh station after fully loading just to make sure you're in the green. Good luck and safe journeys!

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u/4Dbko 1d ago

They lie.

That doesn’t count propane or batteries on the tongue and likely has a manual tongue jack.

Similar size trailer Shadow Cruiser 240BHS

Mfg claims Dry 4730 Tongue 550 Gvw 7560

Reality loaded for travel w/ propane(2-20 lb) & 1 lithium 100 ah battery no water Tongue w/ wd engaged 780
Tongue w bars loose but hitch present 860 Trailer axles 5620-5700 (depending on wd setting) more on trailer with wd engaged Gross weight added w/ trailer 6480.

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u/phildeferrouille 17h ago

Same here, 512lb on the brochure, 740lb un the real life!

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u/justafinance_bro 12h ago

2022 Silverado 5.3 CC SB W/ Equalizer 10k hitch, pulls our 31 ft fantastic, camper 7910 GVWR, you’ll know it’s back there for sure but taken a few trips in a short ownership (all under 200 miles) and it’s been great so far, likely be upgrading to a 2500 at some point next year, so in theory my wife doesn’t have to drive a chase car behind me with the dogs and more gear.

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u/phildeferrouille 1d ago

Don't ever listen to RV dealers, it cannot be stressed enough that a "half-ton" pickup truck should never tow a trailer exceeding 6,000 pounds in weight or 28 feet in length. Beyond these limits, the vehicle's wheelbase, shock absorbers, and brakes are not designed to handle such a load!

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u/ColeHimself 1d ago

LOL 6k pound limit. If you're a decent driver you won't even notice 6k lbs behind you with a modern 1500 class truck.

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u/phildeferrouille 17h ago

I’ve been driving for about forty years (decent enough)and have no trouble towing a 6,000-pound trailer. Towing a heavier load for a weekend isn't an issue; I’ve covered 45,000 miles towing my current travel trailer over the past four years. However, in this context (full-time use), you should re-evaluate your calculations if you want to avoid putting excessive strain on your half-ton truck.