Tire Max Load rating and GAWR

[Mflorant]

I have searched for my answer and find bits and pieces but hopefully someone can answer me:

I have a 2022 Silverado 3500HD DRW

I will be towing a Keystone Fuzion 429 with MAX weight of 19k

I want to get new tires over the stock because I bought the truck used a few months ago.

The tires I am looking at based on reviews and people who are towing similar weight are TOYO Open Country C/T LT295/65R20.

They have a Max Load Dual Rating of 3750

My Trucks GAWR (R) is 10500

Here is my question: Do I take the 3750 x 4 (15,000) and compare to GAWR of 10500 and I am good to go.

or alternately divide the 10500 by 2 (5250) and compare against the 3750 rating x 2 (7500) and still good to go?

I am not asking for tire opinions. These are just one that I am looking at. I want to understand what the max load rating I should be looking for to start with. Thanks in advance!

Mike

[blt2ski]

My question to these questions is, "WHAT" or "WHY" is your RA rating only 10500? Is it springs? axle itselfs rating. or rims or tires? Tires can be multiple issues. THe manufacture may use a tire that is good to the 15000 as you note 4 are good to at 80 psi, I am assuming. OR< they could be rated to 10,500 if you only have say 60 lbs in the tires! In this case, it will not matter if you tires are E/10 ply rated, or D/8 ply rated. That tire size at 60 lbs is good to 10500 total! 
At the end of the day, it is better IMHO to have a bit more tire than spring, rim or axel rating. I've had more issues with tires at max ratings than the other parts I've mentioned. 
Also, that size tire, ALL BRANDS and tread designs have the same max capacity. WITH THAT said or typed in this case. You will find some designs of tires, WILL be better for heaviest of loads ALL the time. Especially ones with steel sidewalls and tread, vs polyester sidewalls and steel tread compounds. Issue with these two designs, is the all steel case tire will weigh upwards of 10-15 lbs per tire. This extra weight does take some HP, along with an MPG drop. Amount will depend upon the motor and drivetrain you have. Ive had .5 mpg with an 05 DA DW going with Toyo M55 vs std Toyo AT tires. Both 215-85-16 LR E. My 1500, the 285-65 LR E tires are 15 lbs heavier than the stock P metric XL 265-65-18 tires. I lost close to 2 mpg, some due to weight, some due to an extra inch diam or 1/2" active radius. Being as the new ones are labeled AT, they really are a true mud/traction tire IMHO vs the stock ones being a HWY tread. ALL of these issues can make or break how a tire works or does not work etc for you. 
My case, two of the tires you are looking at, or the two of the 285's I currently have, will handle the 8000 lbs of GVW my truck maxes out at. I run both tires at 35 front, and 30 in the rear. Otherwise the middle 9 of 11" of tread are in contact with the road at 80 lbs of PSI. 

Probably more info than you need. Your tire capacity is plenty/OVER for the axle rating!

Marty

[Mflorant]

that GAWR 10500 rating is what is on the sticker inside the vehicle. I appreciate the info but still have the question about how the tire max load is calculated vs gawr. 

[blt2ski]

Tire max is based legally at 509 lbs per inch width of tire, or 20k lbs max per axle! Manufactures "warranty" ratings be danged!

Reality, the axle rating is the lowest measure of components. Your tires are good to 15000 lbs at 80 psi. So your warranty performance rating is probably based on springs, or rim capacity.

My navadtar RA is rated to 12200. Due to the four stock tires. My rims are rated to 12600. Springs, axles and brakes to 16500. Legally I was at 19200 per Washington State patrol. Changed out tires to a lower height, wider tire, I'm now at 16000 in tires, I get the max legal rating of 20000. I've been pulled over above the front and rear axle ratings, under federal bridge law ratings, I have yet to get an overnight ticket. Even the time I was 1000 lbs over my paid for gvw. I was given a 10 day up my gvw by 2000lbs.

Reality, you tire capacity is fine!

I can twist your question to many answers depending upon if you worried about warranty, or legal ratings. Reality, assuming you live in a state as I do, you buy tonnage for amount your running down the road, buy enough to cover your total weight! That's ALL a Leo will care about.

Marty

[Mflorant]

My question is really related to the comparison of the tire max load and GAWR (R). I spoke to a tire guy and he said my calculation in my OP was correct. Thanks

[StirCrazy]

is it a 5th wheel or a trailer?  if your towing a trailer you are mainly concerned with the axel weights, so you do the front axel independent of the rear, so all that weight is being added behind your rear axel so it will all go on the rear and the fronts will get a tiny bit lighter, and by using a equalizer hitch you can put a tiny bit of that weight back on to the front's.

if its a 5th then 99% of that weight is going directly on our rear axel if it is set up normal and the fronts don't really change much at all.

[Mflorant]

yes it is a fifth wheel. which is why I was asking about the weight rating on the tires versus the gawr