samosuv

I’ve heard that when tread depth reaches 3/32”, it’s time to replace tires. And for rainy conditions, better to replace them at or before they wear down to 4/32”. And, of course, with new tires, stopping distance in the rain would be “better” than if one had tires with 4/32” tread left.

Just viewed this video by Lexus...

https://www.lexustirecenter.com/?uid...0E250DA7861DA9

I understand that they are trying to sell tires. And I’m not trying to “maximize” the life of my existing tires by waiting until the recommended dimensions in my first paragraph (gleaned from several tire retail websites). But seeing the stopping distances in the Lexus video was surprising, to me at least.

Heck, if there’s _that_ much difference in stopping distances in the rain, I would replace a set of $800 - $1,000 tires when the get down to 50% wear. Smacking into the rear of a vehicle, even with minor damage, would probably raise my insurance rates by at least that much, not to mention damage to my front end.

Your thoughts?

Cheers,
John

ClaytonW

I usually replace my tires at about 4-5 mm (about 5-6/32"). I also need some traction while offroading and for that, the tread depth is very important.

Supra Dr

iTrader: (14)

In PA minimum is 2/32". We start warning customers @ 4-5/32" for the same safety reasons you are concerned about w/ rain & snow.
Some listen, most do not. The problem is they are the ones behind you.

SW17LS

I never let them go below 4/32nds. If its getting to winter and they're at like 5 or so I will replace them then.

samosuv

Thanks to all for your replies. I think I’ll replace mine when they get down to about 5 or 6/32”.

Or I may just put on some 18” rims off of a 2020 LC that I recently bought on eBay. There are so few choices for the 21” rims I have now and the OEM tires are close to $500 each. For the LC rims I’m leaning towards getting the Michelin Defender LTX M/S (285/60R18). The ride will be better too.

Cheers,
John

lexusrus

I usually replace my tires when they get to 4/32. Some of my friends driving government LEOs vehicles get their tires changed out with new tires at 50% worn (at taxpayers expenses, of course).

Some "tire experts" also recommend to have "better tires with more treads" in the rear axles regardless of front wheel drive, rear wheel drive, or all wheel drive.

The following actually had happened to me many years ago. I spun out going about 55mph on an interstate highway in heavy rain. Lucky for me at the end of my spun out I was facing the right direction again so I was able to continue at a lower speed and exit out to a gas station. Nobody got hurt, but my heart sure skipped a few beats.

https://www.tirerack.com/tires/tiret....jsp?techid=52
"However if the front tires have significantly more tread depth than the rear tires, the rear tires will begin to hydroplane and lose traction on wet roads before the fronts. This will cause the vehicle to oversteer (the vehicle will want to spin). Oversteer is far more difficult to control and in addition to the initial distress felt when the rear of the car starts sliding, quickly releasing the gas pedal in an attempt to slow down may actually make it more difficult for the driver to regain control, possibly causing a complete spinout."

samosuv

Glad nobody (and nothing) got hurt in your spinout. Were you in a curve when that happened?

The TireRack comment about releasing the gas pedal makes sense. But I’d still rather have the tires with more treads up front. When braking (to a stop), I think that in general, about 75% (or so) of the braking is fine by the front brakes. That’s why they’re larger up front.

Cheers,
John

lexusrus

This happened on an straight flat interstate highway with two lanes same direction and a wide grassy median with two lanes going the opposite direction. I was approaching an overpass with concrete support beams in the grassy median and on both sides of the shoulders. I was in a high powered two seater roadster, MB SLK55 AMG HARDTOP CONVERTIBLE. The rain was coming down VERY HARD and I slowed down by not hitting the gas nor the brakes trying to maintain a straight course. All of the sudden I heard a whole bunch of beeps with the dreaded red exclamation mark flashing on my center dash (EPS activation). It happened so fast and before I realized I had spun around already and now headed on the CORRECT DIRECTION AGAIN!!! SO SINCE THEN, I pay more attention to my tires!!!

What you said is true in dry roads. But in wet roads, the reverse is true. Also in my case with a high powered rear wheel drive and front engine setup AND WIDE tires. ..... If the rear tires got little or no treads...... You are in for a BIG SURPRISE in the wet roads!!!

samosuv

That happened on a straight stretch of highway? Wow! Awesome convertible also. And again, good thing you came out of it OK. Bottom line, it’s best to have tires with more tread left.

My biggest scare, and this dates me, was when I entered a slowly sweeping 90 degree turn to the right, an interchange from a southbound freeway to a westbound one. For some reason, most of that turn had been worked on and the final layer of asphalt hadn’t been laid down yet. No problemo. The rough gravely turn was bumpy but no biggie. Well, taking that turn at about 65mph, just a little over the suggested speed of maybe 55, my 69 Z28 lost traction. As my rear end started to swing out to the left, I knew enough to turn into it. That was the first and only time I’ve negotiated a turn in a full 4 wheel drift.

I bought one of those tread depth dial gauges on Amazon and my Dunlops measure about 6 or 7/32nds left. Just did a 5 wheel rotation and the never used spare is now on the right rear. I’m hoping to maybe get another 10 or 15,000 miles on these stock 21” LX rims. When the tires need replacement I’ll instead buy new tires for my five 18” LC rims off of a 2020. Got these off of eBay at a great price.

lexusrus

Yes, it happened on a long stretch of flat interstate with lots of rain water pooling on the surface.

Also I would replace the tires when it's at the 6 years old mark EVEN IF WITH LOTS OF TREADS LEFT.

z32

3/32 is the line drawn to replace. I usually replace at 4/32s though. Especially during rainy season and highway driving, the amount of tread depth matters (and of course the tire manufacturer, tread pattern, kind of rubber material on the tire etc)...