Having owned many Volvo's (240's and 740's) and always having experience rotor warpage, I was not surprised to experience the same problem with my 1999 S70 GLT w/25k miles (strong vibration through whole car when braking and slight shimmy in steering wheel. Wheels/tires fine/balanced). When slowing to a stop you get that classic cyclic pulsing feel (as if someone is grabbing the bumper and pulling back every wheel revolution). Yes, lugs nuts are torqued correctly.

Is this a common enough problem that I should expect coverage under warranty?

Common or not, should I expect difficulty in getting it covered? Any tips on how to present this to help with coverage (case of beer in trunk tip noted ;-)?

I noted a TSB about rear brake pads causing vibration. Is this related?

sounds like classic rotor warp. I had this on two prior volvos (240 and current 850) and they were both diagnosed and replaced under warranty by dealer, no hassle. I don't believe you'll find anything in the warranty excluding warped rotors from coverage.

May not be written, but apparently things have changed. They will no longer cover rotors and if they do, it's the dealer doing it for you, not Volvo.

Results from the dealer: warped rear rotors. They charged me $22.00 brake inspection since I didn't have the work done (at almost $400 just for the rotors+labor I can get it done much lower with OEM parts as well). Still think 25k for rotors is a bit on the low side. They did say if it was within 12k they would replace them under warranty.

Service Bulletin Number: 510006

Bulletin Sequence Number: 149

Date of Bulletin: 0004

NHTSA Item Number: SB615014

Make: VOLVO

Model: S70

Year: 1999

Component: BRAKES:HYDRAULIC SYSTEM

Summary: SUBJECT REGARDING NEW REAR BRAKE PADS FOR VIBRATION WHEN BRAKING CONDITION. *TT

Can any techs who frequent this site please look up this TSB?

Thanks!

I think it is common enough that a good dealership will

work with you. Now, a dealership that is not so service

oriented may require some arm-twisting.

I have had no rotor warpage problems on our 855 (53K)

or S70 (27K).

Also, tires can be balanced and still cause problems. I'm

learning all about this with my Bridgestone Potenza RE-730s.

All balance fine. But, when one was put on a sophisticated

wheel balancer (a Hunter 9700) that can place a load (700 lbs)

on the tire it shows a force feedback of 27 lbs. Should

be no more then 4 to 6 lbs. Apparently, this can be caused by

a tire that is out of round, or a stiff spot in the sidewall.

In any case, it balances fine but vibrates at 45 and 80 mph

on the road as though it is out of balance. In this case,

it was easy to tell if it was the tires (I feared it was the

rotors) simply by rotating tires front to rear (vibration gone

when I did that).

Rear rotors are warped, as I suspected. Of course, they want $360.00 to replace them. Gonna wait on THAT one! ;-)

Also found one of those 9700 wheel balance machines at a Mercedes place and they have no problem doing my car, alignment too. Awesome.

Thanks guys.

I understand. However, this vibration coupled with that "pull---pull---pull" feel while coming to a slow stop indicates this isn't tire related, to me.

Have your rotors specd.

Some auto stores now lend or rent special tools. Get the gauge that measures runout (I think that's what it's called) of the rotor (a.k.a. high and low point on the surface of the disc). Check the manual for allowed distortion.

And you should be able to tell whether your rotors are ok or not.

One thing I always wondered about this approach - wouldn't the warpage be different hot vs. cold?

Believe me, I've had Volvo's for a long time now, it's always the rotors. ;-)

I assume temperature should play a role. But Volvo's specs for runout are to be measured cold. Anyways, I wouldn't want to work with a blistering hot rotor.

And here is the info I promised.

Front brake maximum run out = .0015"

Maximum front disc thickness variation = .0003"

Rear brake maximum run out = .003"

Maximum rear disc thickness variation = .0003"

I agree, many Volvo's seem to have problems with their rotors.

When I first got my 94 855T used, it had a bent strut and warped rear rotors.

However, since I've had it, no warping what so ever. I take great care in cleaning the hub with a wire brush when I change from summers to snows and when I rotate half way through the season. So my hubs get brushed 4 times a year minimum. Depending on wear, I sometimes change my summers more often as I drive rather "spiritedly." And I always use a very accurate torque wrench set as close to 81 ft/lbs as humanly possible.

I push my car very hard, so I know it isn't because I baby the car.

I am very protective with my car. I honestly treat it with more love and care than I should. I figure that if I'm going to make my baby run 250km/h, drag race every weekend in the summer, corner the beast on off ramps and on ramps like I'm being chased by the fuzz, I'm going to love her just as much as I push her.

Oh, I forgot to thank you for the response with the specs - THANKS!

Is there a service manual available for this car yet?

Well, I wouldn't say I "baby" the car, but I also don't dig into much either. That being said, the rotors have 25k on them and I haven't removed the wheels. Ever. I don't bother rotating, my experience has been that if I leave the tires where they are and let the fronts wear down the rears are usually close enough. In my opinion, the tires are usually not handling as well in the rain after 3/4 gone anyway and I like the ride of fresh tires. Factory MXV4's lasted about this long and that's fine with me - they are awful in the rain.