Michelin Pilot HX MXM4 issues when mixing variants.

[Mitch]

As is probably well known by now, there are at least two variants of the Michelin Pilot HX MXM4 215/45VR17. The first is the one that came stock on Si's without summer tires and the second came around some time in 2007. The difference is obvious when looking at the sidewalls. The older tire comes down at a slight angle and sticks out enough to sort of protect the outer lip of the wheel. The new tire is just a vertical side wall.

Over the summer I blew a tire due to a road hazard. I had the tire replaced with the new MXM4, but it was on the back so I never noticed. 10,000 mile service includes tire rotation. Of course there's heavy traffic coming out of the dealership, so I didn't notice at first, but as soon as I got on an open road I felt something miserable. Under throttle the car was jerking to the left. I could let go of the steering wheel, depress the gas pedal, and actually watch the steering wheel jerk counter clockwise to a position that would be 11 on a clock.

Well it was cold last night, so I didn't do anything about it until today. I figured that it was one of two things having to do with the new tire being on the front left and the car diving to the left:

1. The new tire is marginally shorter. With the LSD, torque is transfered to the wheel with traction, which is always the tire spinning slower. It's why we chirp/light up the inside tire first in a tight turn on an autocross course. The right front wheel is spinning slower, so more torque is transferred to that wheel. More torque on the right wheel than the left would cause the car to dive left.

2. The new tire is marginally taller. Neglecting the LSD, this would give the right tire a better net gear ratio versus the left, giving it better torque multiplication, and thus causing it to dive to the left.

I'm leaning towards #1 being what's actually happening due to the Si having LSD.

Anyway, I get up today and change the tires on the left side front to back. Now the new tire is on the back again. I torque the lug nuts down to 80 ft-lbs and go for a test drive. Miraculous! The torque steer / left dive is completely gone. My Si is completely neutral under throttle again.

Now a point of interest before going on. The new tire has the same amount of tread as the older tires. What does this mean? The height difference between the wheels is the result of tire wear or tread height. It's a problem with sidewall height.

How does this affect you? Don't always assume that 215/40 is actually 215/40. It's not a definition, but more of an approximation. Don't always assume that two tires with names as specific as Michelin Pilot HX MXM4 215/40VR17 are the same, because they're not.

Why wouldn't Michelin name the tire something slightly different to denote it's incompatibility? Michelin Pilot HX MXM5 215/40VR17 would be enough change to at least say "hey, this tire is a little different, don't mix it with the MXM4s".

Another concern: extended periods of driving with mismatched tires up front could do serious damage to the LSD. I don't want to imagine what would have happened if I had gotten the 10,000 mile service right before heading back to school. As stubborn as I am, I would have just said, "I'll deal with it when I get there". 135 miles at 70mph could have lead to some serious issues that would shorten the life of my differential, possibly even leading to short-term failure.

So again, moral of lesson: You know what happens when you assume...

[habitat]

Originally Posted by Mitch

Why wouldn't Michelin name the tire something slightly different to denote it's incompatibility? Michelin Pilot HX MXM5 215/40VR17 would be enough change to at least say "hey, this tire is a little different, don't mix it with the MXM4s".

Probably because most people tend to replace all tires at once or at least two at a time. Keeping the name is called branding... are you suggesting that when Honda decides to update the civic they should name it something else?

I can understand how it is frustrating for you, but it just seems like a bit of bad timing and bad luck.

[e60.deluxe]

michelin suggests replacing tires in pairs and leaving newer tires on the back.

honestly though im not surprised. some people seem to be saying that the MXM4's are garbage in the wet, i think they're actually quite good and i believe some others have stated the same. i suppose thats the new vs. old.

anyway i cant wait to get rid of these overpriced garbage. instead of paying $210 for these lousy tires i would much rather cough up $130x2 for some decent tire and put em in the back.

[jonesthewine]

Originally Posted by e60.deluxe

i would much rather cough up $130x2 for some decent tire....

....like I did - Goodyear Eagle F1 All Seasons at $131.00 apiece from Tire Rack ;^)

[Izzy]

Originally Posted by e60.deluxe

michelin suggests replacing tires in pairs and leaving newer tires on the back.

honestly though im not surprised. some people seem to be saying that the MXM4's are garbage in the wet, i think they're actually quite good and i believe some others have stated the same. i suppose thats the new vs. old.

anyway i cant wait to get rid of these overpriced garbage. instead of paying $210 for these lousy tires i would much rather cough up $130x2 for some decent tire and put em in the back.

Mine *are* garbage. I can guarantee that. =P

I have what feels like no wet traction, which you say you have some of. And dry traction -- well, that's quite disappointing too.

[e60.deluxe]

as far as wet and dry handling both are garbage, but traction in the wet like stopping power and hooking up from a stop is not too bad..

[chenslee_cheese]

I have a 06 Si, came with the all-seasons. After a week, the car started pulling and the stealership suggested I get them balanced to see if was the tires. I spent $80 getting them balanced without result. I eventually replaced them at the end of 2006 with some 17x8 rims and some Sumitomo tires. The stock rims and tires went in the garage. No more pulling.

Fast forward to last Saturday - My wife and I buy a 2008 LX coupe. I put my ol' 06 rims and tires on and guess what? Pulling.

I have no doubt that these are defective tires.

[HondaFamilyMan]

Originally Posted by Izzy

Mine *are* garbage. I can guarantee that. =P

I have what feels like no wet traction, which you say you have some of. And dry traction -- well, that's quite disappointing too.

I agree 100%. I cannot wait to mount the General Exclaim UHP's sitting in my garage this Spring. Next Winter I will for sure replace the Michelins with winter-specific tires.

[habitat]

Originally Posted by chenslee_cheese

I have a 06 Si, came with the all-seasons. After a week, the car started pulling and the stealership suggested I get them balanced to see if was the tires. I spent $80 getting them balanced without result. I eventually replaced them at the end of 2006 with some 17x8 rims and some Sumitomo tires. The stock rims and tires went in the garage. No more pulling.

Fast forward to last Saturday - My wife and I buy a 2008 LX coupe. I put my ol' 06 rims and tires on and guess what? Pulling.

I have no doubt that these are defective tires.

I wouldn't label them as defective... could just be irregular wear due to driving style or uneven air pressure. That is why tires need to be broken in.

[Izzy]

Originally Posted by e60.deluxe

as far as wet and dry handling both are garbage, but traction in the wet like stopping power and hooking up from a stop is not too bad..

Hooking up is not too much of a problem. Brakes, sort of are. They'd just mercilessly turn on ABS without the slightest compunction. Then again, last real time I used them in the wet -- it was stormy season...

[chenslee_cheese]

Originally Posted by habitat

I wouldn't label them as defective... could just be irregular wear due to driving style or uneven air pressure. That is why tires need to be broken in.

No.

It started pulling within 350 miles, and continued to do so for at least 3000 miles. Pressures were checked, tires were rotated, inspected, rotated again, and balanced. I eventually wrote it off as misalignment, but car was re-aligned and continued to pull. Replacing them fixed the problem, and mounting them on a different car and having the same problem occur was the last test. EVERYTHING pointed to the tires.

[razer]

Originally Posted by Mitch

Over the summer I blew a tire due to a road hazard. I had the tire replaced with the new MXM4, but it was on the back so I never noticed. 10,000 mile service includes tire rotation. Of course there's heavy traffic coming out of the dealership, so I didn't notice at first, but as soon as I got on an open road I felt something miserable. Under throttle the car was jerking to the left. I could let go of the steering wheel, depress the gas pedal, and actually watch the steering wheel jerk counter clockwise to a position that would be 11 on a clock.

this is what happen to me as well.. except that my dealership told me that the new tire was defective and ordered me another but i think its same tire. they put it on the back instead of the front because its ''new"

[habitat]

Originally Posted by chenslee_cheese

No.

It started pulling within 350 miles, and continued to do so for at least 3000 miles. Pressures were checked, tires were rotated, inspected, rotated again, and balanced. I eventually wrote it off as misalignment, but car was re-aligned and continued to pull. Replacing them fixed the problem, and mounting them on a different car and having the same problem occur was the last test. EVERYTHING pointed to the tires.

Alright I agree with you, I'm done defending the tire. I personally think they are too thin and tall and too A/S... I live in CA for a reason! So I can live with summer tires annually!

[Mitch]

Originally Posted by habitat

Probably because most people tend to replace all tires at once or at least two at a time. Keeping the name is called branding... are you suggesting that when Honda decides to update the civic they should name it something else?

I can understand how it is frustrating for you, but it just seems like a bit of bad timing and bad luck.

Your logic is flawed. Sure it doesn't matter that the Civic changes over the years. It's not like the Civic is a subset component of a larger machine. These tires are considered parts. Whenever any part changes in any facet, the part number changes.

Let's say Honda updated the control arms for your car, but didn't change the part number. The new control arms are a little longer to allow for new alignment specifications that come with the latest year of your car. The part numbers are the same, so you don't know which to order. You get the wrong one installed, and now your car doesn't drive right. It doesn't matter how well you align it on a flat surface because as it goes through it's range of motion the new arm gives one side of your car different camber and caster that the other. Now your car dives to the left.

But I guess you should have replaced both control arms at the same time. I mean, that part number is a brand name, despite how obscure that jumble of letters and numbers may seem (HX MXM4 anybody?). Bad timing? Or irresponsible part numbering?

[chenslee_cheese]

I'm with Mitch on this. Part numbering is a basic tenet of engineering and manufacturing. If an updated part can be substituted for the old part without any problems, it simply gets a revision to the part number/drawing. For instance, a ABS sensor wire is simply ziptied to a control arm then later, a clip is added to the control arm to replace the ziptie. Since the parts are compatable without ill effects, a revision to the drawing is all that is needed. If it cannot be substituted, it requires a new part number.

Somewhere in the Michelin system they at least recognize that there are two different designs for this same model tire. They have failed to recognize that the newer tires are incompatible with the older tires when they are mounted across from each other, or they at least failed to communicate this to tire outlets.

Given my problems with my stock set, I think that this model of tire should be avoided in general.

[realxlai]

wow.. great headsup.

[2007SIDAN]

Michelin MXM4's are garbage. They were on my TL. They were on my Accord. They are on my Si. They were on my Acura loaners. I have driven numerous different cars with different sizes (and no doubt, specs) of this tire and all have been miserable. Poor wet traction and easily hydroplane even when they have only 3-4k miles on them. Not to mention, poor tread life. They lasted about 20,000 miles on each car. This tire sucks and on all of my cars has eventually be replaced with Kumho ASX. Now that is a fantastic tire - never a problem.

[Izzy]

Originally Posted by 2007SIDAN

Michelin MXM4's are garbage. They were on my TL. They were on my Accord. They are on my Si. They were on my Acura loaners. I have driven numerous different cars with different sizes (and no doubt, specs) of this tire and all have been miserable. Poor wet traction and easily hydroplane even when they have only 3-4k miles on them. Not to mention, poor tread life. They lasted about 20,000 miles on each car. This tire sucks and on all of my cars has eventually be replaced with Kumho ASX. Now that is a fantastic tire - never a problem.

I actually feel they last an inordinate amount of time. They couldn't wear down fast enough...they had about 80% tread when I took them off with about 10k miles on them, IIRC.

[Mitch]

Originally Posted by Izzy

I actually feel they last an inordinate amount of time. They couldn't wear down fast enough...they had about 80% tread when I took them off with about 10k miles on them, IIRC.

Yeah I can't wait until all four of these tires are spent so I can move on to a good tire.