Would it be cheaper to just buy new rotors? I'm selling the car and want to make sure the pulsation is gone before selling it

 

OK - As far as "Can drilled rotors be resurfaced" - the answer is YES !!! Of course there is a "But" ... Most of the better driller rotors have a slight chamfer around each hole - the shop may be worried that the turning operation will wipe out the chamfer and make the rotor unusable. (The shop may also be worried if they are using an expensive cutting tool on their brake lathe, and they are worried the "interrupted cut" when they pass over each hole will damage the cutting tool). Will the chamfer be removed ?? it's hard to tell. There is a limit to how much metal can be removed from the rotor (typically I think it's somewhere around 0.060" total). (The min thickness is typically cast into each rotor - but it's not typically easy to see - especially if there is rust.) So - the "will it happen" question really comes down to how much metal needs to be removed to get the rotor "cleaned up".

Now - the rotor turning process typically involves two cuts on each face. Both faces are cut simultaneously - (so there isn't a lot of force being transferred through the thinner web to the bolt flange). Normally - the shop will do a rough cut to get both faces flat, then to a slower finish cut to get the surface finish right. You really can't cut less than about 0.003/side at a time - so if you have to take say 0.008/side off to get rid of any runout, and another 0.003/side off to get a smooth surface - you just removed 0.022 from the rotor. Taking 0.011 off a side is probably not enough to ruin the chamfer, but if a heavier cut is required, you can see why the shop would be concerned about ruining the rotor. (BTW - Each "cut" takes a few minutes, and most brake lathes are automatic, so once the cut is started the operator can walk away for a few minutes - the whole rotor cut process typically takes about 10 minutes).

So - my $0.02 - talk to the one shop that gave you a reasonable estimate and ask what the concern is about turning a drilled rotor - if the concern is eliminating the chamfer - you can choose to say - I'm fine with accepting that risk - go ahead and turn them. Take a good look at the rotor before hand, and a good look at it after the cutting, and as long as there is some chamfer left - go ahead and reuse them (the factory puts enough of a chamfer on the holes to allow for normal rotor wear - so the odds are probably in your favor.) If the shop is concerned about their equipment - there is really nothing you can do about that.. But I'd simply buy new rotors rather than paying $150 - $200. Look at either Rock Auto or one of the Chevy Dealers that sells over the internet.

 

DON'T waste your time 'turning' the rotors. Buy two brand new rotors. Old rotors that have been turned almost always pulsate right after, or soon after, they have been turned. I've seen this so many times over the years that I refuse to resurface rotors for customers nowadays. It's always brand new.

I've been doing brake jobs since 1973, when I owned two service stations. I had a machine to turn rotors (and drums too, haha). Back then turning the rotors and drums was standard practice, as those parts were VERY expensive to replace. But now, it's easier (and better) to buy brand new parts. This way, with new parts, you're virtually guaranteed smooth braking for years to come.

There are numerous reasons brakes pulsate. Here's a good page that talks about 'warped' rotors: http://www.stoptech.com/technical-su...nd-other-myths

Bottom line: buy brand new and install carefully. Clean the rotors with brake cleaner before installing, and then don't get any greasy fingerprints on them. Clean the wheel hub and then use a dial caliper to check rotor runout after mounting, I like to see virtually no runout. Tighten the lug nuts to spec, in a couple of increments, using criss-cross pattern.

Smooth braking is easy to achieve, but not with resurfaced rotors. At least, that's been my experience over and over and over..........

 

Over torque to the lug nuts can result in rotors being warped.

If I have any work done by a shop I always check the torque on the lugs when I get home.

Jim

 

Mine ended up bring the front and rear. Replaced all 4 with new brake pads.