Indulge me for a sec. Curb Weight and Tire Pressures?

Yes and I missed that. E requires tables.

 

Are these tables based on vehicle weight?

 

Yes but E tires have a much higher load limit than your truck. Bottom line is if you have a flat tread pattern, you will have no problem with tire wear.

 

You should start with the tire manufacturer. They should have a chart that shows what pressure the tire has to be to support a certain weight. I know there are some threads here with those type charts in them, but it would take a bit of searching for me to find them. If I remember correctly, as the load range goes up, the tire pressure goes up for the same weight rating. In other words, E tires vs. a C tire, the E would have a higher pressure for the same weight rating. If I remember correctly that is. Start with your tire manufacturer.

For example, this is the inflation tables for Toyo tires. You need this for your tires.
https://www.toyotires.com/media/2125/application_of_load_inflation_tables_20170203.pdf
https://www.goodyeartrucktires.com/pdf/resources/publications/2010_loadinflation.pdf

The above is if you are concerned about your tires having adequate weight rating for your heavier truck. If that's not your concern, chalk test them for the weight it has in it most of the time and don't worry about it.

 

I can’t find the inflation tables for BFG KO2s... Anybody have it? I’m running 265/75/16

 

The stock tire placard requires whatever psi is required to attain a 2,149 lb load rating for a P or ISO/ETRTO metric tires.
This translates to a 1,954 lb load requirement when using LT metric or LT flotation tires.
Since you added 2,000 lbs, 1,000 lbs over...you require 2,204 lbs load capacity...1,954+250...250x4=1,000
A 35x12.15R17 attains a load rating of 2,211 lbs at 31 psi.

Being an LT flotation and the large volume, make them "sensitive" load capacity/psi changes.
Between;
25 and 30 psi; 1 psi=56 lbs
30 and 35 psi; 1 psi=50 lbs
35 and 40 psi; 1 psi=44 lbs

Source
https://www.toyotires.com/media/2125/application_of_load_inflation_tables_20170203.pdf

 

37 psi is your adjusted "stock" psi.

 

The brakes are fine. They can stop the truck plus a few thousand pounds in tow. As long as he doesn't have a boat or camper without trailer brakes behind him he'll stop fine.
Brake wear though is another issue because the extra weight and larger tires will chew through brake pads.

 

He's already over what the truck was designed to carry on itself. If he ever loads it up with a few hundred pounds of gear plus a person or two, he will be so far over the legal limit it would not possibly be OK with stock brakes. Remember toyota recommends trailer brakes on any load exceeding 1k pounds if i remember my manual correctly.

 

Do you have a link to your build page? I'd like to see more photos of this beast!

 

Chalk test may work if it’s a radial but not if they are bias ply tires.

That said you can call the manufacturer of the tire and give them your specs. They will advise what psi to run based on load.

 

Thanks for all the info. Some of this is very helpful!

My build page! https://www.tacomaworld.com/threads/tac-toy-build-by-predator-strikeforce.418577/

 

Awesome build! Looks amazing, and more importantly, it's functional! Well done.

 

Thanks, Man.

 

I did a dump run yesterday
I had myself and half a tank of fuel
Was 4800lbs
Have a prinsu rack, 32”k02’s and 2”lift
Not too much added from stock.

6480-4800=1680lbs
Thats really not bad for what you ha e added to tour truck.
Looks awesome btw.

 

I'm probably going to get flagged as the GVWR police with as much as I type this but there's so much more that goes into GVWR besides suspension, drivetrain, and brakes. For example, all the bits of metal your suspension bolts in to that are now holding far more than they were intended to hold. Wheel bearings are another issue that becomes a common point of failure and I'm guessing you're running greater than OEM backspacing, increasing that strain. You also have to realize that while the drivetrain is rated for 1200lbs or so plus another couple thousand in tow, it's not rated to do so in 4Lo. Gravity is a hell of a multiplier and when paired with the transfer case, it's a crazy load on the R&P and axles to move that kind of weight up and down obstacles.

As someone who has spent several years in the automotive industry, it's also not a good thing when insurance comes out for their inspection and voids your policy for negligent use. I've seen several trucks sold for dirt cheap from the body shop after they couldn't afford to get them fixed.

What it comes down to is that going over a few hundred pounds while on the road is within safety margins. Going over 800 lbs (is that even with you in it?) over the GVWR for an off-road truck is just reckless.

 

I once hauled 1830lbs in my little ol' Taco and I got kinda reprimanded in here for it regarding not having the right heavy-duty rear end for that kind of weight etc.
OP your truck is real nice. But we're talking a straight-up one ton of extras. I feel you're asking a lot of that drivetrain but none of my business. Not my truck.
Also, when I see work truck and vans around here and these guys have probably at least that much weight sitting in the back all day every day and those old vans and pickups just keep on going it makes ya wonder if it's really all that bad-2000lbs. I don't know...

 

Some great info here. What tire PSI should I run again?


Just messing with you bud. Thanks for chiming in.

 

Well, Gladiator Tire was no help whatsoever. No surprise there. So I went ahead and did a chalk test which had some surprising results. It looks like 28 pounds is about the magic number on each corner. Thought it would be higher than stock for sure considering the added weight but the E load range must make up the difference. That bugs me a little because the TPMS sensors will go off at 27 or 26 psi so that annoying little light is going to be the bane of my existence!
Nothing some black electrical tape placed in the right location can’t fix. LOL!

 

You can reset those sensors...