This is about my T-Bird, but since it's almost identical to the Mark VIII, I thought I'd ask the experts here.
I just got a new set of Raybestos top of the line PG series rotors and QuietStop pads for the front of my T-Bird. Before the new rotors, the front end was *perfectly* smooth while driving - no vibration at all, (the rotors were a little warped when stopping, though). But after putting on the new rotors and pads, I'm definitely now getting a little vibration through the steering wheel at highway speeds. I was extra sure the hubs were well cleaned before mounting the new rotors, and checked wheel runout after they were back on, and it's perfect - spot on. All lugs were torqued to 90 ft/lbs, and I even have the valve stems in the same position as before. Stopping is perfectly smooth now, so the rotors aren't warped.
The only thing I can come up with is that one or both of the front rotors isn't balanced - does anyone know if machine shops or any other place can balance rotors, I imagine by grinding a little out of the vane area, like I've seen on other new rotors? Even though Raybestos' web page says these are balanced, I saw no evidence on either rotor that any weight had been removed anywhere, and wonder if they somehow slipped through...
Thanks for any suggestions.
John
'97 Mark VIII LSC
'96 T-Bird 4.6 LX
I just got a new set of Raybestos top of the line PG series rotors and QuietStop pads for the front of my T-Bird. Before the new rotors, the front end was *perfectly* smooth while driving - no vibration at all, (the rotors were a little warped when stopping, though). But after putting on the new rotors and pads, I'm definitely now getting a little vibration through the steering wheel at highway speeds. I was extra sure the hubs were well cleaned before mounting the new rotors, and checked wheel runout after they were back on, and it's perfect - spot on. All lugs were torqued to 90 ft/lbs, and I even have the valve stems in the same position as before. Stopping is perfectly smooth now, so the rotors aren't warped.
The only thing I can come up with is that one or both of the front rotors isn't balanced - does anyone know if machine shops or any other place can balance rotors, I imagine by grinding a little out of the vane area, like I've seen on other new rotors? Even though Raybestos' web page says these are balanced, I saw no evidence on either rotor that any weight had been removed anywhere, and wonder if they somehow slipped through...
Thanks for any suggestions.
John
'97 Mark VIII LSC
'96 T-Bird 4.6 LX