FIXED - Problems with Michelin Crossclimate + tyres on Octavia VRS TDI184 4x4

[varaderoguy]

Folks,

 

As always - this is a sounding board.  My (project) Diesel Octavia 3 VRS (4x4) have just had a set of Bridgestone Potenza tyres replaced - with a set of Michelin CrossClimate + tyres.

 

I am not a hooner (generally) and very careful how I scrub in tyres (ex.biker).  I've done about 100 miles, but I have to report that I am extremely disappointed with the CrossClimate tyres.  They are downright dangerous on my VRS.

 

My complaints are:

 

1) They are unpredictable - they either oversteer or understeer when turning into corners.

2) The tyres have ruined my MPG (from a healthy 45mpg at normal driving) to a disasterous 30mpg.

 

I have complained to both Michelin and also the tyre dealer who fitted them - the tyre dealer is trying to fob me off saying "they've never had any issues before".  Michelin want me to go to an ATS Euromaster garage to get the tyres investigated.  They don't inspire confidence.

 

Before anybody asks, Yes - I have checked the tyre pressures and the tyres which are a 225/40 R18 92Y tyre - are all running at between 2.4 and 2.5 bar - about 35 to 36psi (which is standard pressure).  I know that the VRS's are hard on their tyres, but I would have to say to avoid using these tyres of these cars - its not a good combination.

 

 

Edited 19 July, 2021 by varaderoguy
Edit title

[varaderoguy]

old tyres:

[varaderoguy]

Good news - I'm booked into ATS Euromaster for diagnosis and assistance on Wednesday.  More news to follow soon.

[xman]

They are directional tyres, sounds like one or more are mounted the wrong way round. Will ruin handling, mpg and wear 

 

Check the direction of rotation arrow carefully on the sidewalls. The V pattern in the tread should be pointing in the forward direction of rotation.

Edited 28 June, 2021 by xman

[varaderoguy]

Gents. Just checked....all 4 directions are correct. I'm going out to record a little video on my favourite road and put it up.

[skomaz]

I used cross climates on our 'tweaked' 4x4 Estate TDI for a number of years, albeit in a slightly smaller size (205/55 R16 94V in both standard and XL ratings).  I found they were excellent and never had a problem with them - they certainly weren't unpredictable (they were anything but in my experience) and were very grippy indeed.  Tyre pressures did need to be a couple of psi higher than recommended though.

[Schtum]

I've got 225/50x17 CrossClimate + on my remapped, c. 185 bhp Yeti 4x4.  I'm an ageing hooligan and often thrash it mercilessly.  They work really well for me.  I particularly like the steering feel that the rounded tread profile gives. 

[SurreyJohn]

Remember all brand new tyres, can be bit unpredictable for first few dozen miles as there is often a coating (tyre mould release agent) on the surface.   Some tyre places also leave rather a lot of gummy glue from tyre label on it.   This scrubs off.

 

I am wondering if your poor mileage is due to excess coating of this substance, might also be causing the steering oddities if it is scrubbing off unevenly.

 

I once had a mobile fitter come to replace a tyre and he left part of the labels stuck on outside of tyre and told me they will come off when driving !  
 

 

[varaderoguy]

To show you the understeer and oversteering problems..... (at 36psi/2.5bar)

Edited 29 June, 2021 by varaderoguy

[KenONeill]

13 minutes ago, varaderoguy said:

To show you the understeer and oversteering problems

Yeah; don't know what pace you made through there on the old Bridgestones but you were catching the guy in front.

[J.R.]

I cant see the slip angles from the video and have to rely on your commentary, the speedo reading seemed reasonable and you were following a vehicle that was not being driven quickly, quite sedately I would have said.

 

I would not expect any under or oversteer from a 4x4 vehicle under those circumstances.

 

It's a shame that we couldn't see the steering wheel.

[Ootohere]

Best get those tyres replaced because that is handling pathetically

 

100 miles are just scrubbing in though.

?

Have you tried just a few PSI difference front and rear, and are the pressures set with an accurate gauge?

[varaderoguy]

9 hours ago, KenONeill said:

Yeah; don't know what pace you made through there on the old Bridgestones but you were catching the guy in front.

In all fairness, about the same. I would have been able to go through those corners without issue on the old tyres.

[varaderoguy]

6 hours ago, e-Roottoot said:

Have you tried just a few PSI difference front and rear, and are the pressures set with an accurate gauge?

So - I have a separate digital tyre pressure meter for our tyres. Those tyres are being shown at 36psi/2.5bar. I was thinking of taking the tyres up to 38psi/2.6bar for comparison. 

 

The driving experience is like driving on marbles and the tyres are going around a corner, not gripping and then gripping. That's what I mean when I say it's alarming (in terms of the handling).

Edited 29 June, 2021 by varaderoguy

[varaderoguy]

10 hours ago, skomaz said:

Tyre pressures did need to be a couple of psi higher than recommended though

Okay....I think you have a good point. I will try the tyres at 38psi and even at 40psi to get try to get them to perform normally and when it get colder, they need to operate on a lower psi.

[Breezy_Pete]

Is fake tyres a thing?

[varaderoguy]

Yes, but unlikely. I'll be trying higher pressures today and see how we get on. I'll let you know when I visit ATS Euromaster and get feedback from them.

[varaderoguy]

Today is another day - and I've increased the pressure up to 38psi on all tyres on the VRS.  This has definately made an improvement.  The understeer has now almost all disappeared, although you can still feel the flexing of the tyre, its not dangerous any longer.

I am going to let the tyres and the car cool down, later on today - I'll take the pressures up to 40psi and see how we get on with things.

 

However, the MPG still sucks at 38psi - I cannot (even with gentle driving) get the car above 35mpg. 

[AGFalco]

12 hours ago, varaderoguy said:

I visit ATS Euromaster

 Are owned by Michelin. Note.

 

Thanks, AG Falco

[xman]

Still convinced the tyres might be fitted wrong way round for those poor mpg figures. Michelin are normally in the top tier for fuel economy.

 

I wonder if your geometry is way out and the bridgestones being non directional tolerated or adapted to it.

 

All season tyres are always going to handle much softer than a summer tyre because of the softer compounds and more flexible tread patterns.

 

Lets see what the tyre centre says.

[J.R.]

The increase in fuel consumption seems too much for tyre compound alone, effectively  the new tyres would be consuming 1.5 litres of diesel from every gallon, that is one hell of a lot of heat energy and you would really notice it by the smell and tyre wear.

[Schtum]

I've just watched the video.  It's hard to see the extent to which the car is actually understeering and oversteering without seeing your steering wheel inputs.  

 

Off the wall - your car should have XDS+ enabled.  Is something corrupting the data that's fed to the ECU?   I know that XDS+ works by nibbling at the inside front and rear wheel brakes when those wheels are unloaded in a corner.  I don't know where that information originates from.  

 

Have you had the car scanned with VCDS to see if it's thrown any fault codes?   

[varaderoguy]

No error codes as far as I am aware but I'll check tomorrow and report back.

[Breezy_Pete]

Some of the apparent economy loss will be because the car will be travelling further per wheel revolution than with the old tyres, especially if well worn, I think. 

Can't be bothered to do any sums just now, but can't imagine that would account for much.

[varaderoguy]

29 minutes ago, J.R. said:

you would really notice it by the smell and tyre wear.

The tyre does smell very rubbery as they are very new tyres and I had considered a wheel alignment problem. Good news is that I am visiting West End Skoda on Tuesday next week so we'll see what happens.