Ideal tread depth for replacement?

[Slartibardfast1]

I know minimum legal tread depth is 1.6mm but what is "ideal" depth for replacements do you think? I don't want to wait until barely legal but I also don't want to be replacing when there's enough tread for reasonable performance. These days my driving style is "comfort" rather than "performance". Car is S Class W221 S350L with 20" Alloys (Michelin Sport 4s)

 

[Blobcat]

3mm is where the Police used to change on their traffic cars

 

[onefortheroad]

My c250 with continental tyres let me know when. Pulling away in the wet was a no go. Id have to agree that they were about 3mm and pretty useless tbh.

1.6mm is time To change ,it's not a"safe" legal limit , more of a legal limit.

 

[rorywquin]

1.6mm That is the legal safe limit and seems to be a standard for manufacturers and many countries but motoring associations etc will recommend more. However ......

How to Check Tyre Tread to Avoid Driving on a Part Worn Tyre | MICHELIN

Checking your tyres regularly is essential for your safety. Tyre tread will inevitably wear down over time. Read MICHELIN's guide and learn how to confirm tyre tread depth.

www.michelin.co.uk

 

[brandwooddixon]

I tend to start looking to change when down to 3mm.
Water dispersing action is much reduce (if at all) once below that, so expect much reduced traction in the wet.

 

[rorywquin]

I tend to start looking to change when down to 3mm.
Water dispersing action is much reduce (if at all) once below that, so expect much reduced traction in the wet.

I tend to think that if quality tyre brands like Michelin 'et al' say 1.6 is ok then, 1.6 is what I’ll use. However, if I was on some cheapo tyres I’d probably change sooner and also for old tyres.

 

[onefortheroad]

I tend to think that if quality tyre brands like Michelin 'et al' say 1.6 is ok then, 1.6 is what I’ll use. However, if I was on some cheapo tyres I’d probably change sooner and also for old tyres.

I'm fairly sure the tests they carry out are on new tyres with maybe 8mm of tread not 1.6 mm . Even at 1.6 mm it's time to change ,asap.

 

[rorywquin]

I'm fairly sure the tests they carry out are on new tyres with maybe 8mm of tread not 1.6 mm . Even at 1.6 mm it's time to change ,asap.

Of course they test with new tyres - that was not my point. Of course it is time to change at 1.6mm (or shortly before - 1.65mm or even 2mm??) - otherwise you are then going past the legal limit.

1.6mm is the absolute minimum for safety - hence the depth indicators built into tyres is 1.6mm. MOT & Manufcturers say 1.6 mm so why should it be anything greater than 1.6?

There is the bbb, "belt & braces brigade” that carry 2 spares, a full set of tools, jump starters, space blankets, back up gps, emergency flares and MREs etc etc who, would probably say replace at 4mm.

However, as the saying goes “opinions are like @$$holes everyone has one". That includes me. However I’m happy to follow the recommendations of organisations & people qualified to make recommendations like MOT guidelines and tyre manufacturers.

 

[onefortheroad]

Of course they test with new tyres - that was not my point. Of course it is time to change at 1.6mm (or shortly before - 1.65mm or even 2mm??) - otherwise you are then going past the legal limit.

1.6mm is the absolute minimum for safety - hence the depth indicators built into tyres is 1.6mm. MOT & Manufcturers say 1.6 mm so why should it be anything greater than 1.6?

There is the bbb, "belt & braces brigade” that carry 2 spares, a full set of tools, jump starters, space blankets, back up gps, emergency flares and MREs etc etc who, would probably say replace at 4mm.

However, as the saying goes “opinions are like @$$holes everyone has one". That includes me. However I’m happy to follow the recommendations of organisations & people qualified to make recommendations like MOT guidelines and tyre manufacturers.

So what is your point . Leave till 1.6mm then change , or ?

 

[rorywquin]

So what is your point . Leave till 1.6mm then change , or ?

“My opinion” is that as manufacturers build in 1.6mm depth markers into the tyre (and explain how to use them) and MOT requirement is 1.6mm, I see no reason not to use that benchmark.

However I personally make sure that I replace them shortly before getting to 1.6mm (say 1.7 or 2mm) but that is more for my convenience that I want to get them done and not go past the legal limit & usually end up with some unused rubber. Particularly on the more sporty cars I have owned. I tend to drive hard and fast.

OP mentioned that his driving style is sedate (& on quality tyres) so I cannot imagine why he would need to change his tyres before ~1.6mm.

I imagine that even at 1.6mm there is still some margin of safety built into that.

 

[onefortheroad]

“My opinion” is that as manufacturers build in 1.6mm depth markers into the tyre (and explain how to use them) and MOT requirement is 1.6mm, I see no reason not to use that benchmark. However I personally make sure that I replace them shortly before getting to 1.6mm (say 1.8 or 2mm) but that is more for my convenience that I want to get them done and not go past the legal limit & usually end up with some unused rubber.

I imagine that even @1.6mm there is still some margin of safety built into that.

Sounds about right for most tbh.
Margin of safety I'd think in the wet ,would be greatly reduced ,in cornering,hard braking ,steering . Anything that's torquey infact. In the dry probably as good as slicks at 1.6 mm .

 

[rorywquin]

Sounds about right for most tbh.

Weird how replies here work, you'd replied before I’d completed & posted my reply. Not the first time.

 

[onefortheroad]

Weird how replies here work, you'd replied before I’d completed & posted my reply. Not the first time.

I'm done with it now so not to worry. Having a nice cup of Yorkshire

 

[rorywquin]

I'm done with it now so not to worry. Having a nice cup of Yorkshire

Wasn’t having a go at you. Seems that a reply post can be read while someone is still typing it. Tea is exactly what I was about to do & it is Yorkshire tea even-though I’m not British.

 

[s5tuart]

Like all things, it depends!
Age of the tyres would be a significant factor for me, as would the brand.
I changed the Pirelli’s on the CLS even though they had 5mm ish left because they were starting to show signs of perishing.
With good condition Premium or mid range tyres I would start doing my research around the 2mm mark. With low mid range or budget tyres it would probably be around the 3mm mark.
time for a cup of tea now!

 

[rorywquin]

Like all things, it depends!
Age of the tyres would be a significant factor for me, as would the brand.
I changed the Pirelli’s on the CLS even though they had 5mm ish left because they were starting to show signs of perishing.
With good condition Premium or mid range tyres I would start doing my research around the 2mm mark. With low mid range or budget tyres it would probably be around the 3mm mark.
time for a cup of tea now!

Oh yes! Common sense should prevail. I replaced a pair of perfectly tyres (on my Old B Class - god I hate driving that car.......) with good tread depth because they were 8 years old.

 

[DSK]

At 3mm I’m thinking of replacing in my head. Then at about 2.5/2mm they are changed typically speaking. The tyres I run such as F1’s and Pilot Sport have good consistency down to 2mm but, I like to not run them lower to ensure some decent depth for the severe wet weathers.

Mine were usually always good enough to sell as part worns and even had a few regulars specifically asking for them.


Sent from my iPhone using Tapatalk

 

[Srdl]

The time of year often influences my decision, perhaps a bit irrationally? If they are getting low (I can’t define what I mean by that) in the Autumn, I will usually change them then because I don’t want to go through winter on low tread rubber. If it is Spring, however, I would probably run them through the summer because they would cope perfectly well with mostly dry and hotter times. I run summer tyres all year round.

 

[harrye500]

Changed all 4 on the 207 on Saturday. Advisory on last years mot re rear n/s tread. Front walls were also crazing on my inspection so I did them all. Drives like a new car!

 

[rorywquin]

Changed all 4 on the 207 on Saturday. Advisory on last years mot re rear n/s tread. Front walls were also crazing on my inspection so I did them all. Drives like a new car!

When we changed the rears last year, the car had gone from the MOT (passed and no commets) to the indy for a service who, spotted and reported tyres cracking.