Tire Load Rating

[davidbeitz]

I'm buying new tires for my t4r and have a question about load rating. I'm looking at the PIRELLI SCORPION ATR which is available in two different load ratings, 113 and 121. I understand the 113 will be consistent with the OEM tires however I am looking at towing a 4k trailer and wondered if it would be a good idea to upgrade to the 121 load rated tires. I assume the 121's would be heavier and give a rougher ride but hold up better to towing? The trailer tongue weight is ~400 lbs less stuff in the TV and trailer.

Any comments would be appreciated!

 

[rightyouareken]

The stock load rating will handle the full GVWR/tow rating of the 4Runner safely, but whether it “feels” how you want it to feel is another matter. P metric tires like the stock or 113 load rating tires tend to have softer sidewalks and can “wallow” a bit under load. LT tires tend to be heavier and stiffer which can lead to a rougher ride empty but a more “planted” confident ride when loaded. Your call whether the trade offs are worth it to you.

Another thing to note is that LT tires require a higher tire pressure to meet their load ratings than a P tire. That 121 load rating is probably a load range E tire. To get the full load rating you’d need to run up to 80psi which would be an insanely rough ride.

Here’s some more reading for you. https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=55

Sent from my iPhone using Tapatalk

 

[JLTD]

Nice post rightyouareken, that about covers it.

Although I might add that the P-metric tires are usually run at a pressure a bit lower than maximum.

When towing I add pressure to both front and rear, which takes care of the wallowing.

Start at max and see how it rides, you can always lose a little pressure down the road if you need to.

 

[jp.vegas]

Most E or 121 load rating tires only need about 40-42 psi to match the load rating of the stock tire. The stock load rating is more than enough, as mentioned, to deal with the max gvwr of the vehicle which includes tongue weight while towing.

The only time you need 80 psi in a 121 tire is to reach *its* maximum load rating, which exceeds the factory spec load rating of the 113 tire by a considerable amount. You never need to run 80 psi in those tires on a 4Runner.

If you really want to dig into the details, find a set of tire load inflation charts online.

 

[fkheath]

Higher load rated tires have more cords on the tread and side wall, thus are heavier but more durable. You really don't need higher load rated tires unless you do a lot of extreme off roading where you need the extra toughness on rocks and boulders. As for tire pressure, just use the tire pressure on the drivers door jam sticker.

 

[RedSled]

Higher load rated tires have more cords on the tread and side wall, thus are heavier but more durable. You really don't need higher load rated tires unless you do a lot of extreme off roading where you need the extra toughness on rocks and boulders. As for tire pressure, just use the tire pressure on the drivers door jam sticker.

That sticker is only for oem size tires.

 

[4_YOTA]

can you post a picture of the PIRELLI SCORPION ATR because I never seen those tire with a aspect ratio of a 4runner...always seen them on pickups running very low profile

 

[Mutant138]

285 121s rode like shit when my truck was stock weight.

Getting better the more weight I add (full steel skids / sliders).

Hope that is helpful data.

 

[davidbeitz]

can you post a picture of the PIRELLI SCORPION ATR because I never seen those tire with a aspect ratio of a 4runner...always seen them on pickups running very low profile

Well crap, called today and found that the tire had been discontinued!

 

[Tuco S.]

E rated tires for a 4Runner seems like overkill to me. BFG offers a KO2 in C and also an oddball D load rating, although the D may be discontinued. I haven't looked in a while.

A buddy of mine has E rated Toyo Open Country II's on his 1st gen. Tundra and that thing drives like a dump truck.

 

[JB.]

I'm buying new tires for my t4r and have a question about load rating. I'm looking at the PIRELLI SCORPION ATR which is available in two different load ratings, 113 and 121. I understand the 113 will be consistent with the OEM tires however I am looking at towing a 4k trailer and wondered if it would be a good idea to upgrade to the 121 load rated tires. I assume the 121's would be heavier and give a rougher ride but hold up better to towing? The trailer tongue weight is ~400 lbs less stuff in the TV and trailer.

Any comments would be appreciated!

The 121 would be an LT tire in load D (assuming 265/70/17).

You'd no doubt like the tow handling better than with the stock P-metric tire. Depends how much towing you do. The question is whether the trade-off would be worth it to you - heavier, stiffer riding (but more so because of the extra air pressure, not the tire itself all that much) quite possibly not as good wet traction, etc.

If you want to did into the pressure relationship, see below.

LT tires need more air pressure.

 

[02SE]

The 121 would be an LT tire in load D (assuming 265/70/17).

You'd no doubt like the tow handling better than with the stock P-metric tire. Depends how much towing you do. The question is whether the trade-off would be worth it to you - heavier, stiffer riding (but more so because of the extra air pressure, not the tire itself all that much) quite possibly not as good wet traction, etc.

If you want to did into the pressure relationship, see below.

LT tires need more air pressure.

The LT 265/70R17 tires I have are load range E, with a 121 load index.

 

[MAST4R]

285 121s rode like shit when my truck was stock weight.

Getting better the more weight I add (full steel skids / sliders).

Hope that is helpful data.

Yup. ^

Weight helps as does a stiffer suspension.

Basically, soft suspension goes well with SL tires.

Offroad suspension, by contrast, plays well with E load.

Weight will help with E load feel either way.

As for tire pressures, the Toyo load rating table is available on the internet. It can tell exactly what pressures correspond to what loads when moving to LT.

Finally, 265 70 17 121 tires are E load. D load would be 118.

 

[JB.]

The LT 265/70R17 tires I have are load range E, with a 121 load index.

Yeah, that's right. My error. The mere fact that you can hardly find a load D these days should have clued me in to that.

Happily, that detail changes very little of what I wrote to the OP.

 

[AZ Craig]

Well crap, called today and found that the tire had been discontinued!

I believe the Pirelli Scorpion All Terrain Plus effectively replaced it. Seems like a much more advanced and modern tire all around and very good for on road and potentially light offroad (think gravel roads, etc.) applications. Also snowflake rated.

It was a little too wimpy for my consideration for when I'm in desert rocks and what not.

 

[Dollar Retriever]

I recommend load range e, 10 ply tires.

My stock oem Bridgestone tires f$cked up in 1st week on forest service road.

Whatever the brands you looking for, make sure get 6 ply or 10 ply. They are stiffer but stronger.


Sent from my Casio Calculator using Tapatalk