SL55/63/65/R230 AMG: Cowl Shake in SL55
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Mercedes Benz
Cowl Shake in SL55
Recently I went from having Michelin PS2 tires on my SL55 to having the new P-Zero. I also have RENNtech Monolite 19 inch wheels with 255 and 295 tires for the record. Now the PS2 as we all know is a sponge of a tire and it made the car wiggle all over the road. I went through the car replacing everything in the suspension thinking it was just totally worn out at 40k miles but that only helped a bit.
I purchased new tires and it was back to being a straight and stable car. Trouble is I have increased cowl shake on all but the smoothest roads. Now I never had anything other than the Michelin tires on the 19 inch wheels but I dont recall the vibrating over bumps with the OEM 18's. The P-zero is significantly stiffer than the Michelin (and thats why I purchased them) but I want to make sure all is normal.
So the question is this... Who has noticed the car having cowl shake? Do you have upgraded wheels? What tires do you run and does the shaking bother you?
Its not terrible but you clearly know its not a fixed roof vehicle. I have driven CLK63 cabs and those cars are so sloppy its amazing anyone buys them. I just get slightly surprised when I drive on sections of the 405 in southern california (west LA) and the car just vibrates! Its not balance related as I have had the tire re-balanced twice and it was the same each time.
I purchased new tires and it was back to being a straight and stable car. Trouble is I have increased cowl shake on all but the smoothest roads. Now I never had anything other than the Michelin tires on the 19 inch wheels but I dont recall the vibrating over bumps with the OEM 18's. The P-zero is significantly stiffer than the Michelin (and thats why I purchased them) but I want to make sure all is normal.
So the question is this... Who has noticed the car having cowl shake? Do you have upgraded wheels? What tires do you run and does the shaking bother you?
Its not terrible but you clearly know its not a fixed roof vehicle. I have driven CLK63 cabs and those cars are so sloppy its amazing anyone buys them. I just get slightly surprised when I drive on sections of the 405 in southern california (west LA) and the car just vibrates! Its not balance related as I have had the tire re-balanced twice and it was the same each time.
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GLC 63 S AMG / Corvette C8 / Jaguar SVR
I have those tires on the optional 18s (the black series looking wheels) and I have 255/285s and there is nothing like this you speak of. I do however, even with 18s, have a firmer ride then with any others tires on 18s i have driven on.. its definitely the tire.
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From: Southern, CA.
V12-Biturbo
I upgraded to aftermarket 19" wheels & 295 Michelin PS2's frigging car was downright dangerous even on frwy punching it while changing lanes felt like rollover was imminent...Switching to P-Zero 295's cured ALL, NO cowl shake @ any speeds (I've ran her hard in all situations, even on the crummy 405)
I'm using 265/35/19 Michelin PS2 up front feels great, I read about the softer sidewalls on MP's & my fronts were nearly new, so I ONLY replaced rears...
The stiff sidewall up front is the problem, you only need the P-zero's or comparable brand w/stiff sidewall on rear, I know it's odd but WTF it works...
Try letting some air outt've the fronts until you can replace them, it softens them up a bit.
I'm using 265/35/19 Michelin PS2 up front feels great, I read about the softer sidewalls on MP's & my fronts were nearly new, so I ONLY replaced rears...
The stiff sidewall up front is the problem, you only need the P-zero's or comparable brand w/stiff sidewall on rear, I know it's odd but WTF it works...
Try letting some air outt've the fronts until you can replace them, it softens them up a bit.
Last edited by Thericker; May 28, 2009 at 01:16 AM.
