Problem with Michelin Pilot Sports on C5
Discussion
I heard that some drivers have had problems with the Michelin Pilot Sports on the C5. I'm wondering if what I encountered last week was the same problem.
Left my home in the North East for Florida early evening. According to the computer weather, was going to have snow from New York through Pennsylvania, which turned out to be accurate. We had replaced the run-flats with the Sports and was very happy with them due to quieter running, and good performance in the wet. Turns out these tires do not like snow, or icy conditions. Spun at 25mph right in front of a tractor trailer while trying to change lanes to let him past. Fortunately, he was going about the same speed as me, not the usual 65, like all the others. He was able to stop. Just got the car stopped, backed up, and moving again in the right hand lane just in time to allow enough room for another tractor trailer to squeeze between us at about 60 mph. A couple of seconds sooner, and he would have punted me half way to Florida. All told, we drove about 6 hours through the dark, averaging about 25 mph.
When we started to encounter some dry patches of pavement, it started to feel like I had a loose wheel. Actually pulled over and shook each wheel to see if I did.
Eventually, when I got to a rest area, I actually put a wrench on a nut on each wheel to see if they were loose.
The car would start "jumping", and I was getting noises like a bad universal. This would happen with the traction control in the off and on position. Almost thought about stopping and waiting for Chevrolet dealer to open so we could check the car.
I did notice the worst problems were when the road had traction cuts in it, the cuts going from the left side to the right side of the road, and also if one side of the car was on dry pavemnet, and the other side was on ice.
Eventually when we reached "all dry" conditions, the car returned to normal handling, and we stopped thinking about renting a car for the rest of the trip.
Wondering if anyone else has encountered this problem, and if Michelin has suggested a different alignment setup for their tires.
thanks
Jack
Left my home in the North East for Florida early evening. According to the computer weather, was going to have snow from New York through Pennsylvania, which turned out to be accurate. We had replaced the run-flats with the Sports and was very happy with them due to quieter running, and good performance in the wet. Turns out these tires do not like snow, or icy conditions. Spun at 25mph right in front of a tractor trailer while trying to change lanes to let him past. Fortunately, he was going about the same speed as me, not the usual 65, like all the others. He was able to stop. Just got the car stopped, backed up, and moving again in the right hand lane just in time to allow enough room for another tractor trailer to squeeze between us at about 60 mph. A couple of seconds sooner, and he would have punted me half way to Florida. All told, we drove about 6 hours through the dark, averaging about 25 mph.
When we started to encounter some dry patches of pavement, it started to feel like I had a loose wheel. Actually pulled over and shook each wheel to see if I did.
Eventually, when I got to a rest area, I actually put a wrench on a nut on each wheel to see if they were loose.
The car would start "jumping", and I was getting noises like a bad universal. This would happen with the traction control in the off and on position. Almost thought about stopping and waiting for Chevrolet dealer to open so we could check the car.
I did notice the worst problems were when the road had traction cuts in it, the cuts going from the left side to the right side of the road, and also if one side of the car was on dry pavemnet, and the other side was on ice.
Eventually when we reached "all dry" conditions, the car returned to normal handling, and we stopped thinking about renting a car for the rest of the trip.
Wondering if anyone else has encountered this problem, and if Michelin has suggested a different alignment setup for their tires.
thanks
Jack
I know that Michelin make Pilot Sports in a winter version for the US market. Different tread compound and pattern which will work better in the cold and wet. Chances are you have the summer version which will work well in warm and cool weather but might go a bit hard in the cold and ice
What pressure were you running in the tyres ? Somethimes you have to play about a bit to get the best behaviour out of them.
My cheapo Falkens worked fine in the inch of snow we had yesterday and which turned to ice overnight. Easy enough getting to work at 05:30 today !
What pressure were you running in the tyres ? Somethimes you have to play about a bit to get the best behaviour out of them.
My cheapo Falkens worked fine in the inch of snow we had yesterday and which turned to ice overnight. Easy enough getting to work at 05:30 today !
Jack, this is an interesting post. It seems to me that you are actually describing the cars reaction to tires being with/without traction.
The tires could have an effect, but maybe the cars characteristics are the topic?
I had a situation that at first seems quite different, but is actually similar, in my ZR1. I started what was a pretty long thread on Corvette forum.
Here is the link:
http://forums.corvetteforum.com/zerothread?id=727220
I am late for an appointment, I would like to re-visit, and discuss this with you later.
Thanks, and regards,
Art in Baton Rouge, LA USA
The tires could have an effect, but maybe the cars characteristics are the topic?
I had a situation that at first seems quite different, but is actually similar, in my ZR1. I started what was a pretty long thread on Corvette forum.
Here is the link:
http://forums.corvetteforum.com/zerothread?id=727220
I am late for an appointment, I would like to re-visit, and discuss this with you later.
Thanks, and regards,
Art in Baton Rouge, LA USA
Tho the title and the post talk about the tire question, I thought it was pretty clear that USCANAM was describing the cars reaction to the circumstances of tires losing and regaining their grip. In that sense, it is a tire issue. But I am interested in the description of what the car did, which seems to be a mechanical "clunking" and shifting of attitude because of the grip changes.
When I posted my description of what my C4 did on CorvetteForum, I was stunned by how many responses described similar characteristics. My situation seems different, in that I was on dry ground, and ran over pea gravel thrown in the lane, when I was in a sharp right turn at 30mph with the engine 'dragging" down on the car.
But from the cars standpoint, the situation was essentially the same. One wheel suddenly lost grip, and the car reacted severly. An instant later, the tire regained traction, changing the cars dynamic. Unfortunately, I had already started to correct based on the first situation.
So I think the issue is sudden loss of traction by one wheel, and a severe reaction of the car, perhaps aggrivated by the action of the limited slip rear axle.
In the other thread, we did not conclude that the Corvette was defective, but that with enough horsepower, a limited slip, and independant suspension, the car can react violently (pull side to side, for one example) when traction suddenly changes. it is surprising how many people had similar results when they were in low power situations, and therefore did not expect a traction issue.
In this situation, the ice caused a situation similar to the pea gravel in my case. It caused a loss of traction that was "random", and not controllable by controlling power.
This was a C5? with traction control on? Most of the ones in my thread were C4's (obviously), without traction control. But the actions of the car were very similar. Perhaps the traction control also made the front wheels participate in this phenomenom? So the question is, what causes it? Looked at another way, I think my old Ford Explorer, with a straight axle and no posi, would react very differently. Actually it would be more controllable in these low speed situations, I think.
Regards, Art in Baton Rouge, LA USA
When I posted my description of what my C4 did on CorvetteForum, I was stunned by how many responses described similar characteristics. My situation seems different, in that I was on dry ground, and ran over pea gravel thrown in the lane, when I was in a sharp right turn at 30mph with the engine 'dragging" down on the car.
But from the cars standpoint, the situation was essentially the same. One wheel suddenly lost grip, and the car reacted severly. An instant later, the tire regained traction, changing the cars dynamic. Unfortunately, I had already started to correct based on the first situation.
So I think the issue is sudden loss of traction by one wheel, and a severe reaction of the car, perhaps aggrivated by the action of the limited slip rear axle.
In the other thread, we did not conclude that the Corvette was defective, but that with enough horsepower, a limited slip, and independant suspension, the car can react violently (pull side to side, for one example) when traction suddenly changes. it is surprising how many people had similar results when they were in low power situations, and therefore did not expect a traction issue.
In this situation, the ice caused a situation similar to the pea gravel in my case. It caused a loss of traction that was "random", and not controllable by controlling power.
This was a C5? with traction control on? Most of the ones in my thread were C4's (obviously), without traction control. But the actions of the car were very similar. Perhaps the traction control also made the front wheels participate in this phenomenom? So the question is, what causes it? Looked at another way, I think my old Ford Explorer, with a straight axle and no posi, would react very differently. Actually it would be more controllable in these low speed situations, I think.
Regards, Art in Baton Rouge, LA USA
I've been driving my C5 for five years in all weathers and do not recognise this problem at all. I use standard tires and do not have active handling.
However, the traction control on my car is not very aggressive compared to other cars I have owned. i.e. the back of the car will step out quite a long way under power in slippery conditions before the traction control cuts in. Maybe this same characteristic could cause the juddering symptoms described in a straight line if the driver did not realise that the traction contol was being activated? With 350 bhp and wide tires you need a gentle right foot in slippery conditions.
However, the traction control on my car is not very aggressive compared to other cars I have owned. i.e. the back of the car will step out quite a long way under power in slippery conditions before the traction control cuts in. Maybe this same characteristic could cause the juddering symptoms described in a straight line if the driver did not realise that the traction contol was being activated? With 350 bhp and wide tires you need a gentle right foot in slippery conditions.
Tire width!
That's a very good point. One of the ideas that came up was that the combination of power and very wide tires (obviously good for traction in good conditions)actually made the car sensitive to this issue. Could make the change from grip to no grip very sudden. The C5 has slightly more narrow tires (still wide!), for various stated reasons, and the ZR1 has the widest tires ever on a production Corvette, but a less sophisticated suspension.
The ideas comming up here are consistent with what we thought before. Perhaps the Corvette is one of those cars where winter tires are really a necessity, not just because dry performance tires can't hold (that would be an issue with any car), but because of the car's reaction. I also presume that this is true of cars similar to the Corvette, like Viper, Ferrari, etc, but there are fewer of them on the road.
I hope more will post, this is very helpful, and once I get my suspension repaired, I will show more respect for the car, especially in low speed scenarios where traction is an issue.
I wonder, Jack, if this is any help for you. If we assume that your car does not have any defects, which ruins any discussion, do you think any of this applies to what you felt?
Regards, Art
www.artcolleys.net/picturethumbs.htm
That's a very good point. One of the ideas that came up was that the combination of power and very wide tires (obviously good for traction in good conditions)actually made the car sensitive to this issue. Could make the change from grip to no grip very sudden. The C5 has slightly more narrow tires (still wide!), for various stated reasons, and the ZR1 has the widest tires ever on a production Corvette, but a less sophisticated suspension.
The ideas comming up here are consistent with what we thought before. Perhaps the Corvette is one of those cars where winter tires are really a necessity, not just because dry performance tires can't hold (that would be an issue with any car), but because of the car's reaction. I also presume that this is true of cars similar to the Corvette, like Viper, Ferrari, etc, but there are fewer of them on the road.
I hope more will post, this is very helpful, and once I get my suspension repaired, I will show more respect for the car, especially in low speed scenarios where traction is an issue.
I wonder, Jack, if this is any help for you. If we assume that your car does not have any defects, which ruins any discussion, do you think any of this applies to what you felt?
Regards, Art
www.artcolleys.net/picturethumbs.htm
[quote=
I wonder, Jack, if this is any help for you. If we assume that your car does not have any defects, which ruins any discussion, do you think any of this applies to what you felt?
Regards, Art
[/quote]
Art
Thanks for your input.
After the snow and ice were gone, we continued on, and with the return trip, logged another 2500 miles.
The car was fine, and handled normal.
We have three cars in our racing stable, and have the equipment to do all the alignment on them and the C5.
The C5 was just done when the Sports were installed, and we were impressed by the handling and noise improvement just driving on the street.
Some of the indications when on the ice and snow were of a car that had toe-out on the rear wheels, which we know is not the case. The only other input I can add is because I knew I was going to encounter some snow, we had the tire pressures 3 pounds lower, at 27psi, which may have been a mistake.
The next step is to see IF Michelin will respond with any suggestions re: alignment, pressures etc.
Will update if I hear back from them
Regards
Jack
I wonder, Jack, if this is any help for you. If we assume that your car does not have any defects, which ruins any discussion, do you think any of this applies to what you felt?
Regards, Art
[/quote]
Art
Thanks for your input.
After the snow and ice were gone, we continued on, and with the return trip, logged another 2500 miles.
The car was fine, and handled normal.
We have three cars in our racing stable, and have the equipment to do all the alignment on them and the C5.
The C5 was just done when the Sports were installed, and we were impressed by the handling and noise improvement just driving on the street.
Some of the indications when on the ice and snow were of a car that had toe-out on the rear wheels, which we know is not the case. The only other input I can add is because I knew I was going to encounter some snow, we had the tire pressures 3 pounds lower, at 27psi, which may have been a mistake.
The next step is to see IF Michelin will respond with any suggestions re: alignment, pressures etc.
Will update if I hear back from them
Regards
Jack
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