Goodyear Wrangler DuraTrac Tire inflation

[asnatlas]

I found the following while I was searching:

Weight of Truck
--------------------------- x Max tire PSI as indicated on sidewall
Tire max load rating (lbs)
multiplied by 4


A 4th Gen 4Runner (2004) is listed at 5710lbs on the door sticker.

I have the the LT265/70R-17, Duratrac Tire by Goodyear which has a Max Load of 2470lbs @ 50 PSI

I rounded up to 6000 / 9880 = 60.

Now do I :

50 PSI x 60% = 30PSI
or
50 PSI x 40% = 20 PSI

When I dropped my tires down to 30 PSI they still seem "over inflated" but 20 PSI seems a bit low. I plan on doing a caulk test but wanted to get some input.

 

[Clemsonfan15]

You have the "C" load?

I would say like 35-40. Some people say go even higher.

 

[asnatlas]

You have the "C" load?

I would say like 35-40. Some people say go even higher.

Yes, I have the C load range.

I know some people inflate up to 40 PSI or so. I am looking for "maximum contact" so that I get even tread wear on the entire tire. Without a "chalk test" even at 30 PSI they seem "over inflated"

 

[JB.]

When I dropped my tires down to 30 PSI they still seem "over inflated" but 20 PSI seems a bit low. I plan on doing a caulk test but wanted to get some input.

You can alter pressure to achieve various goals, but the logical starting point is the door sticker. It gives pressure for P-metric tires. In order to achieve the same load reserve as the door sticker pressure, you need about 44psi because Duratrac is an LT, and LTs carry less load at the same psi compared to P.

There's a lot of load reserve in the stock spec so you might decide you don't need that much, but at 44psi they will wear much better than at 30 which, by the way, would be risky long term, especially in a Q-speed rated tire like Duratrac. 30psi is the P-metric equivalent of less than 20.

Personally, I'd forget about the chalk test. It's not that great in the first place, but even less so for an off-road tire.

 

[Clemsonfan15]

You can alter pressure to achieve various goals, but the logical starting point is the door sticker. It gives pressure for P-metric tires. In order to achieve the same load reserve as the door sticker pressure, you need about 44psi because Duratrac is an LT, and LTs carry less load at the same psi compared to P.

There's a lot of load reserve in the stock spec so you might decide you don't need that much, but at 44psi they will wear much better than at 30 which, by the way, would be risky long term, especially in a Q-speed rated tire like Duratrac. 30psi is the P-metric equivalent of less than 20.

Personally, I'd forget about the chalk test. It's not that great in the first place, but even less so for an off-road tire.

So 44 isn't too much? Even if the max is 50?

 

[JB.]

So 44 isn't too much? Even if the max is 50?

No. Max tire psi is an independent number and the tire could handle it easily.

 

[iDRiVaT4R]

I wouldn't be driving around with 44 psi in a load C tire. That's kinda overkill IMO. I'm running 275/70r16 load D and have about 37psi cold. When they warm up it increases to about 39-40psi. I'm probably gonna go down to 35psi cold as at 37 psi they look perfectly flat. Of course I drive with no extra weight most of the time.

44 psi seems more reasonable for a load E tire which many are running.

 

[RonMAIDEN]

Your 4Runner also doesn't weigh that much,the 5700lbs is gross vehicle weight meaning fully loaded with passengers/cargo. The actual weight of a 4th gen is around 4500lbs.

 

[JB.]

I wouldn't be driving around with 44 psi in a load C tire. That's kinda overkill IMO. I'm running 275/70r16 load D and have about 37psi cold. When they warm up it increases to about 39-40psi. I'm probably gonna go down to 35psi cold as at 37 psi they look perfectly flat. Of course I drive with no extra weight most of the time.

44 psi seems more reasonable for a load E tire which many are running.

Whether load C,D, or E, the load carrying capacity is the same at 37 or any psi. It's the fact of being LT instead of P that changes the equation. The psi should be tailored to the load, not the tire, as long as max tire psi isn't exceeded.

The OEM load capacity represents the ability to carry gross vehicle weight with a healthy reserve left over. Load reserve is a good thing - the more the better - and has been on the rise in OE tire specs, especially since Ford/Firestone.

 

[CNJ Runner]

imo 40-psi is too much. I have 265/70/17 c load duratracs, at 40psi i was getting bad vibrations at 55-65 mph, and early signs of cupping on the backs of the treadblocks. I have since been running 35 psi with my better results.

 

[CNJ Runner]

o yeah, and if anyone is wonderin or comes along this thread wondering if it will fit in the spare tire location, it fit with no problem on my 06 sr5

 

[Calif-4runner]

Yes, I have the C load range.

I know some people inflate up to 40 PSI or so. I am looking for "maximum contact" so that I get even tread wear on the entire tire. Without a "chalk test" even at 30 PSI they seem "over inflated"

I have the "E" rated 265/70-17 and the max psi is 80lbs. The dealer filled them at 50lbs which is about 62% of max.

They seemed a bit harsh at 50 psi so I reduced them to 40 psi and it rides much better. So I'm running 50% of max pressure when not towing if that helps. If and when I tow, I would up the pressure according to the load.