Tire Towing question

Before my lift was installed the 265/70/17 was the largest tire I could run on my stock suspension. I wanted to go up from 265/70/17 but wasn't sure about this issue. Naturally, I went bigger and ordered the E rated KO2’s from my trusted tire shop, the 10 ply KO2 AT 285/70/17. The manager later talked me out of them when I called to confirm my appt for a set of C rated in the same tire. He said the side wall was the same 3mm thick sidewall as the 10 ply and recommended the C rated tire said it exceeded the payload capability of the truck anyway and that the 10 ply E tire was overkill for my Tacoma. I use my 4x4 everyday to get up to my house probably 60/40 on road/ off road and tow a 12’ aluminum boat.

So far, I’m happy with C rated tires off road performance. Picked up and threw some rocks but not to bad, runs pretty quite which surprised me. Ran on out sloped, rocky dry washouts this hunting season with no issues. I do have a great suspension so that helps the ride a lot.

 

Did Russage13 say anything about off road use? Going from a 265-70/16 to a 265-75/16 is roughly a 3 percent increase give or take based on brand. If stock gearing is 3.73 you would need to go to 3.88's to maintain the same overall effective ratio that you had with stock tire size. Will you notice it? I did but not enough to justify a re-gear. If I would go to 285-75/16 I would re-gear to at least 4.11's. The one thing that has not been mentioned is breaking. Towing the boat will put more stress on breaks so if you added a larger tire and went with D or E rated tires both of which are way overkill for load capacity will also increase demand on breaks. Go up to 265-75/16's at most and just stay with P-metric. My P-metric Cooper AT 3's actually have a higher load capacity than the C's.

 

Since you say that you don’t really off-road much I’d buy the Michelin LTX at2. They are a great tire. Then I’d swap the leaf springs to the all pro expeditions then add timbrens.

 

Interesting, thanks for the reply.

 

When moving from P to LT tires, you have to change tire pressure too. Toyo has a conversion chart on their website.

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

 

Interesting read. Thanks for the reference.

I really don't think the average persons (including myself) is going to apply this information. Certainly anyone serious about overlanding their vehicle (with a heavy pack) may need to closely observe the more stringent tire pressure regulations. However. even though I may be totally wrong in thinking so, I don't believe that 2 or 3 PSI is really going to make a lot of difference for the average individual. So, using the OE sticker PSI recommendations isn't really that far fetched. I think most individuals get into trouble after purchasing commercial rated tire is when they notice the "maximum" rated pressure of the new tire and think that it's OK to push those limits.
Just my $0.02

 

Tires change more than 2-3 psi from cold in morning to hot in afternoon. I’m with ya on the psi change being insignificant.

One thing to be aware of from my personal experience is that I’ve only owned two Tacoma’s, a 2015 sr5 and my 2019 trd off road. Both have towed more than they should have. With this in mind, understand that I traded my first Tacoma in with around 87/88,0000 miles and replaced the stock tires at 55,000 miles. My truck now has around 9k miles and still stock tires. So whatever rating the stock tires were/are they held up just fine. This said, your truck can safely handle up to 6500 pounds without a flinch on the stock setup if your load is properly balanced and secured and you have trailer brakes with a trailer brake controller. Truck would likely be able to tow around 8,000 pounds without any hiccup also due to ratings always being lower than what something can actually handle.

 

I think you missed the point of the load charts though. Running an E load LT tire at 29-32 psi, depending on what stock tires you have, is severely under-inflating them. Stock tires are rated to ~2000 pounds at stock pressures. Per the linked chart, to have an equivalent weight capacity as the stock P tires a LT tire usually needs to be inflated to 40-45psi.