Stock Dunlops Cracking. Replace?

[DiscoCam]

Hello everyone! It's been a while since I've posted here but I guess that's a good thing because I haven't had any problems with my 4Runner until now. Well except for a few paintless dent repairs but I digress.
Anyway, my 2016 SR5 only has 19k miles on it (daily driver, short commute). I've been on top of maintenance as I am with all my vehicles, that includes 5k mile tire rotations.

My 4Runner came with the Dunlop Grandtreks instead of the Duelers. They seem to have a few thousand miles left of tread, but the sidewalls have begun to crack. I have attached pictures. This is the same story for all four tires. Kind of disappointing especially because I had no intention of replacing them until they wore out. I know that they're not the best tires, but they do ok for a highway commute.

So what should I do? I don't like to mess around with tires, so cracked sidewalls make me feel uneasy. But the cracking is not too bad yet.

If I replace them, I will likely get a set of KO2s or Michelin Defender LTXs.

Thanks in advance for the advice.

EDIT: Tire manufacture dates are all 3615 so just about 3 years old.

 

[Thrasher_S]

Personally, I would use this as an excuse to upgrade. That said, I ran a pair of Michelins on a commuter car for nearly 90k miles. They were cracked worse than this when I sold the car. I brought it up with the tech who was rotating them for me (every 5k like clockwork), and he didn't think there was anything to worry about. Since he stood to profit by telling me to replace them, I figured it's probably not too bad.

 

[Nick B]

Two completely different tires you mentioned for replacements.
Have you looked at the Firestone Destination AT ? I’ve had great luck with them both on the highway and light off road. Long wearing also .

 

[Jeffy]

Personally, I wouldn't worry about that.

And just my .02: Stay away from the KO2s on a daily driver, they suck in the rain. I'm waiting for mine to wear out so I can find something that sticks to a wet highway better, I slide around a lot in storms even when I'm going slow. People are flying by me with no problem while I'm sliding going only 50mph. And that's with 12/32 of tread left.

 

[Antman]

Nothing wrong with those tires.

 

[Nick B]

Personally, I wouldn't worry about that.

And just my .02: Stay away from the KO2s on a daily driver, they suck in the rain. I'm waiting for mine to wear out so I can find something that sticks to a wet highway better, I slide around a lot in storms even when I'm going slow. People are flying by me with no problem while I'm sliding going only 50mph. And that's with 12/32 of tread left.

Have you tried adjusting the pressure up or down to see if it makes a difference ?

 

[Jeffy]

Have you tried adjusting the pressure up or down to see if it makes a difference ?

Tried, really doesn't make much difference at all. There's just no siping on the tires.

 

[DiscoCam]

Two completely different tires you mentioned for replacements.
Have you looked at the Firestone Destination AT ? I’ve had great luck with them both on the highway and light off road. Long wearing also .

Yes I know that they are very different. I have not yet decided how much off roading I would like to do with my 4Runner. But considering that I have a dedicated trail rig, probably not much so the Michelins should do fine.

I have been using Michelin for years, but recently got a set of KO2s on my first gen sequoia. Liking them a lot so far.

Thank you everyone for the opinions so far.

 

[DiscoCam]

Tried, really doesn't make much difference at all. There's just no siping on the tires.

Very strange that you have had issues with KO2s in the rain. Do you have the Load Range E or C spec?

I have the E load on my 04 Sequoia in 265/70/R17 (stock 4Runner size, slight bump up from the sequoia). Running at 32psi (stock pressure). Haven't been in rain with it yet, but they have been fantastic off road and ride well. America's Tire pumped them up to 37psi and the truck rode like crap; back to 32 and it rides almost like the SL range LTX M/S2s that were on it before.

But the sequoia is about a thousand pounds heavier than the 4Runner so that could make a difference.

Heavily leaning towards the Defender LTXs on my 4Runner. Michelin has a $70 rebate now so I might just get them swapped out before that ends.

 

[Jeffy]

Very strange that you have had issues with KO2s in the rain. Do you have the Load Range E or C spec?

I have the E load on my 04 Sequoia in 265/70/R17 (stock 4Runner size, slight bump up from the sequoia). Running at 32psi (stock pressure). Haven't been in rain with it yet, but they have been fantastic off road and ride well. America's Tire pumped them up to 37psi and the truck rode like crap; back to 32 and it rides almost like the SL range LTX M/S2s that were on it before.

But the sequoia is about a thousand pounds heavier than the 4Runner so that could make a difference.

Heavily leaning towards the Defender LTXs on my 4Runner. Michelin has a $70 rebate now so I might just get them swapped out before that ends.

They're actually a "D" load. I agree, they feel great and are excellent off road, I just hate them in the rain. And since it's my daily driver and I can't just stop driving on rainy days, they're getting switched out to something new once they're worn out

 

[SlickTRD]

Very strange that you have had issues with KO2s in the rain. Do you have the Load Range E or C spec?

I have the E load on my 04 Sequoia in 265/70/R17 (stock 4Runner size, slight bump up from the sequoia). Running at 32psi (stock pressure). Haven't been in rain with it yet, but they have been fantastic off road and ride well. America's Tire pumped them up to 37psi and the truck rode like crap; back to 32 and it rides almost like the SL range LTX M/S2s that were on it before.

But the sequoia is about a thousand pounds heavier than the 4Runner so that could make a difference.

Heavily leaning towards the Defender LTXs on my 4Runner. Michelin has a $70 rebate now so I might just get them swapped out before that ends.

I think it has to do with the KO2 low or lack of silica content. Silica has been shown to increase wet performance and you will see other manufacturers like Michelin use it in their tires.

The dry rot/cracking on your tires is not significant, I wouldn't hesitate to change them to the LTX for safety alone.

 

[91324]

I just switched from my stock 265/70/17 Dunlop Grandtrek AT20s at 31,000 miles to 275/70/17 KO2s. They are E class, so a bit heavier, but I haven't had any issues in the rain. I'm running them at 40 PSI.

 

[The Waco Kid]

I think it has to do with the KO2 low or lack of silica content. Silica has been shown to increase wet performance and you will see other manufacturers like Michelin use it in their tires.

The dry rot/cracking on your tires is not significant, I wouldn't hesitate to change them to the LTX for safety alone.

KO2s also lack proper channeling for water to escape quickly, compared to other AT tires. They're made for gripping desert and rock type terrain, so its logical that their faults would include rain performance.

 

[<<<<]

Your tires are fine but you're over inflating them. Based on your pic the tread does not make contact with pavement along entire width of "contact" area.

 

[DiscoCam]

Your tires are fine but you're over inflating them. Based on your pic the tread does not make contact with pavement along entire width of "contact" area.

They are at stock pressure and I check that every week.

I had just washed it and put tire shine on before I took the pictures so some got on the sides of the tread.

 

[The Waco Kid]

They are at stock pressure and I check that every week.

I had just washed it and put tire shine on before I took the pictures so some got on the sides of the tread.

He's talking about the lack of siping on in the middle of the tire. That's an indication that you're over inflated as the tread has worn down to a point to where the little squiggles are less visible compared to the tread closer to the sidewall. Also, your tread depth in the center looks to be shorter than that of the tread nearest the sidewall. Using the head a penny or quarter as a gauge, you should be able to tell for sure.

In an opposite situation of that, if you were under inflated, the tread nearest the sidewall would be more worn, while the middle would look new.

https://www.tirebuyer.com/education/tire-pressure-and-performance

 

[DiscoCam]

Personally, I would use this as an excuse to upgrade. That said, I ran a pair of Michelins on a commuter car for nearly 90k miles. They were cracked worse than this when I sold the car. I brought it up with the tech who was rotating them for me (every 5k like clockwork), and he didn't think there was anything to worry about. Since he stood to profit by telling me to replace them, I figured it's probably not too bad.

Used it as an excuse to upgrade to the Defender LTX. Went with the E rated version, so far I haven't really noticed a difference in ride quality (not a bad thing). Will post pictures. Made sure that they are at 32psi so I don't have anymore abnormal wear. Thanks everyone for your input, much appreciated.

Anyone think that the reason why KO2s have not so great wet road performance is because of the 4Runner's weight? Maybe they do better on a heavier vehicle? I have them on my sequoia, no issues so far except I've only driven it in the rain twice. But it weighs a lot more than the 4Runner and the 4WD can be used in the rain because of the center diff. My neighbor has an OBS F250 powerstroke, he swears by the KO2s. Actually used to use Michelin until a few years ago. But that thing is even heavier than a sequoia.