Tundra, Norweld and Fleet Camper 8280 lbs

[JiminMaine]

We had decent weather this past week here in Maine and decided to have the truck weighed. The Cat scales read 8280 lbs with 3/4 tank of petrol. This includes two adults with absolutely nothing else in the truck or camper. Slightly alarmed at first, the Tundra has been built to take this weight.
I am finding it difficult to find a suitable tyre pressure. I attempted the max E rating when cold (80psi) though the ride was unbearably harsh. I noticed the camper juddering several times. Has any member with a similar build/setup found a comfortable tyre pressure?

 

[Taku]

Hmm, actually not sure what our combo weighs, but it is a 21 Tundra long bed with an ATC Cougar camper shell on it I built out. Likely lighter than your setup. We run 50# in the front and 55# in the back with Cooper Discover tires and am just about ready to replace them at 53K miles (they have a few thousand left in them but bad roads with sharp rocks are just around the corner). I do deflate them to about #25 when we be on washboard or rough roads for a long stretch.

 

[JiminMaine]

Thanks! I tried 50, 55, 60 front and 55, 60, 65 rear. Etc
Once the truck is ready to hit the road we will be close to 9000 lbs. A member suggested the calk test, which I will do once the salt is off the roads here. In addition I have read all the tyre related posted here on WTW.

 

[Vic Harder]

Chalk test, or an inexpensive pyrometer. Puma/Grandby with lots of gear, full size diesel truck, canoe on top, etc... I run 60 psi front and rear.

 

[jiminruskin]

I had a tundra with an AT Summit on it with Cooper 285/75R18 E rated tires. My truck loaded with lots of gear was very similar to your weight. Not knowing what tires you have I can tell you my tires were rated at 4080#'s at 80 PSI, doing the math those tires are capable of carrying over 12,000 pounds. You have to bring the pressures way down, I used to run mine between 35-40 PSI for a decent ride.

Using a load to pressure chart assuming you had similar rating on your tires you could use the chart and see that your cat scale says you have 1950#'s on each wheel in the front and 2190 #'s on the rear (give or take a little). This chart shows that you could be around 35-40 psi. Keeping in mind the tire pressure will go up @5-8 psi after they get hot. This chart is for Toyo tires but can be used for most tires. This should be a good starting point and I will bet it will agree pretty close with a chalk test.

https://www.toyotires.com/media/pxcjubjs/application_of_load_inflation_tables_20200723.pdf

 

[JiminMaine]

Jim, I truly appreciate you taking the time to share a thoughtful response. Also to the members who have reached out privately, thank you!
I too have the same tyres as you. I will try the 35 45 cold test later on today. When we picked up the camper in December all four wheels were at 35psi and the ride was incredibly comfortable. I completely underestimated the factual weight of the camper and as a result went down the rabbit hole. Thanks for the reminder of how much weight the actual tyres are rated for.

 

[Starbrightsteve]

We had decent weather this past week here in Maine and decided to have the truck weighed. The Cat scales read 8280 lbs with 3/4 tank of petrol. This includes two adults with absolutely nothing else in the truck or camper. Slightly alarmed at first, the Tundra has been built to take this weight.
I am finding it difficult to find a suitable tyre pressure. I attempted the max E rating when cold (80psi) though the ride was unbearably harsh. I noticed the camper juddering several times. Has any member with a similar build/setup found a comfortable tyre pressure?

Your statement that”the Tundra has been built to take this weight” has me puzzled. Now I know that Toyota makes excellent vehicles. I don’t know what Toyota listed as your payload but I know Tundras don’t have 3500 or 4000 lb payloads. If Toyota built the truck to handle the weight you loaded onto it, why don’t they say so or call it a 3/4 or one ton pickup?

 

[JiminMaine]

It's a great question. However, this has been covered for years on various websites. Possibly here, but certainly Expedition portal. On a stock Tundra you are limited to what the engineer's have designed. As with many similar builds to mine, this Tundra is no longer a stock vehicle. I intend to share a complete build post here on WTW once it's finished. Still have the truck interior to address and a special trip to Woodland, Ca before that happens.

 

[GVWRLOL]

Jim, I truly appreciate you taking the time to share a thoughtful response. Also to the members who have reached out privately, thank you!
I too have the same tyres as you. I will try the 35 45 cold test later on today. When we picked up the camper in December all four wheels were at 35psi and the ride was incredibly comfortable. I completely underestimated the factual weight of the camper and as a result went down the rabbit hole. Thanks for the reminder of how much weight the actual tyres are rated for.

Just gotta say that is an excellent tire/wheel combo and fitment.

 

[GVWRLOL]

It's a great question. However, this has been covered for years on various websites. Possibly here, but certainly Expedition portal. On a stock Tundra you are limited to what the engineer's have designed. As with many similar builds to mine, this Tundra is no longer a stock vehicle. I intend to share a complete build post here on WTW once it's finished. Still have the truck interior to address and a special trip to Woodland, Ca before that happens.

Have you done any frame mods? I'm at a much lower weight on my 18 crewmax (7140) and right up until I saw your numbers I was thinking it's pretty sketchy. I've done bags, 5100s, and the RAS and it seems pretty happy but I still worry about being overweight a bit. I won't lie your BIG numbers made me a lil more comfortable with sending it.

 

[JiminMaine]

No frame mods. Though the Tundra is built for the weight. Dobinson hd suspension all round. Power brakes, air bags, too much farkle. Mainline overland did our build. It's comparable with Tight loops fly and Bound for nowhere's build. We opted for the fleet oppose to the hawk due to the cab over height difference.
You do notice the weight when you add water. 20 gal in the camper and 11 gallons in the norweld. Today, to see what I would expect to carry, I threw a bunch of gear, food, a bluetti, solar briefcase in the camper and took it out for a shake down test. 200 miles averaging 10.6 mpg and then to the weight station after filing up. 8860 lbs! The truck drove great!

 

[GVWRLOL]

No frame mods. Though the Tundra is built for the weight. Dobinson hd suspension all round. Power brakes, air bags, too much farkle. Mainline overland did our build. It's comparable with Tight loops fly and Bound for nowhere's build. We opted for the fleet oppose to the hawk due to the cab over height difference.
You do notice the weight when you add water. 20 gal in the camper and 11 gallons in the norweld. Today, to see what I would expect to carry, I threw a bunch of gear, food, a bluetti, solar briefcase in the camper and took it out for a shake down test. 200 miles averaging 10.6 mpg and then to the weight station after filing up. 8860 lbs! The truck drove great!

awesome!! your rig is a thing of beauty. This is my current rear set up with 6112s up front. im on the fence about if I should go toytec or OME for the coil upgrade. I havent even considered dobinson, im just looking to get a lil more support and maybe let some air out the bags. How have they held up? it seems like youre pretty happy with them

 

[JiminMaine]

Thanks! I would take a serious look at Dobinsons. I have them on my tacoma build. Also switched out my ome in my old 80 series too. What psi do you have in your bags? They look pretty extended. My air bags are barely inflated at present. I intend to use them more for balancing/leveling when needed. I don't know what which leafs you have. If you haven't already I would look at Deavers for leaf springs, their custom options are perfect.

 

[GVWRLOL]

I've found what Im calling a sweet spot for now at 70psi but the ride is still pretty jarring. I've checked out Alcan, Deaver, and icon for a spring pack, I think it's going to more than likely come down to what my budget can allow.

 

[bajaphile]

Just curious, what does the door jam sticker state for GVWR? Is it more than 8280 lbs?

For a pressure calculator based off your stock tire and stock air pressure, you can use this as a guideline.

Tire Pressure Calculator

Easy to use tire pressure calculator. Use our tire pressure calculator to calculate the new tire pressure needed when changing tire sizes.

tiresize.com

 

[JiminMaine]

Thanks! The current weight of the camper is 91020 lbs fully loaded. This obviously exceeds the stock Tundra GVWR. This rig is no longer stock and has been built to take the weight. Truck handles amazing at 35psi front, 45 rear.

 

[Jon R]

I have a 2021 GMC 3500 hd CCLB gas with a fully equipped Grandby. The front axle weight is 4550 lbs and the rear is 4900 with the camper. I run 55 psi in the fronts and 65 in the rears. I would run the rears at 55 as well for better ride quality but my tpms alarms at 62. I have the stock 18 inch Michelins E rated tires.

 

[GVWRLOL]

my tpms alarms at 62.

im not familiar with GMC but on the toyota you can set the alarm. there is probably a procedure in the owners manual to adjust it. usually involves a button somewhere near the OBD2 port or steering column.

 

[GVWRLOL]

Thanks! The current weight of the camper is 91020 lbs fully loaded. This obviously exceeds the stock Tundra GVWR. This rig is no longer stock and has been built to take the weight. Truck handles amazing at 35psi front, 45 rear.

safe travels and most importantly... have fun yall.

 

[Jon R]

im not familiar with GMC but on the toyota you can set the alarm. there is probably a procedure in the owners manual to adjust it. usually involves a button somewhere near the OBD2 port or steering column.

Thanks. My understanding is that on my GMC it can be set to a different point with the right aftermarket external device, and others have done it. I haven’t been motivated enough to buy the device.