Replacing F/R Pads, should I turn Rotors?

[redwag]

Going with Axxis Ultimates Front and Delux in the rear, but do I need to turn the rotors when replacing the pads?

Thx

[MisterX]

If your rotors are very badly grooved, turn them. Otherwise, just install your new pads. Turning rotors is a peculiarly American thing to do. Most European mechanics just slap the pads on and have at it knowing everything is just fine.

I'd like to know where the idea of turning rotors at every brake job came from. Does anyone here know the answer? My suspicions lead me to believe it comes from the mass marketing of automotive services. Pep Boys, Sears, whoever, advertise a brake special and adding turned rotors seems to attract customers.

A few years ago (now that I think of it, quite a few years ago) I dropped a car at a service shop for brakes. The Service Tech called with the bad news - my rotors needed turning and the price of the job was going to increase by over a hundred dollars. Since I usually did my own brakes, I knew the cost of turning rotors was about six bucks each, if that. I told the bastard, "Don't do a thing, I'll be right over to pick up the car."

X

[redwag]

Thanks X

[dark_rex]

Originally posted by MisterX
If your rotors are very badly grooved, turn them. Otherwise, just install your new pads. Turning rotors is a peculiarly American thing to do. Most European mechanics just slap the pads on and have at it knowing everything is just fine.

I'd like to know where the idea of turning rotors at every brake job came from. Does anyone here know the answer? My suspicions lead me to believe it comes from the mass marketing of automotive services. Pep Boys, Sears, whoever, advertise a brake special and adding turned rotors seems to attract customers.

A few years ago (now that I think of it, quite a few years ago) I dropped a car at a service shop for brakes. The Service Tech called with the bad news - my rotors needed turning and the price of the job was going to increase by over a hundred dollars. Since I usually did my own brakes, I knew the cost of turning rotors was about six bucks each, if that. I told the bastard, "Don't do a thing, I'll be right over to pick up the car."

X

agree with X. we used to turn rotors a lot at the store (i almost turned mine) i think it's 90% crap to be honest. i added new front pads on about 10K miles ago. still feel great on the original rotors unturned.

dR

[tan]

If the runout is out, get them turned.

If it's fine, lightly sand them in circular motion to get a circular-cross hatch markings. This improves the bedding of the pads.

Pep Boys charge an extra $10 to $20 per rotor to get them turned. Most places will remove the rotor and turn them.

Few places have the equipement to turn them while the rotor is on the car (preferred method these days)

[redwag]

I plan on installing the pads myself with the help of a mechanic frienmd. How does this job rate on a difficulty scale?? He's a very knowledgible tech, so with him there I'm not too worried, but I don't know if it's something the manual will get me through on my own...

Also, does anyone know what type of grease the manual specs for the rar side of the pad? It would be nice to use something other than getting it from the dealer.

[MisterX]

I forgot about runout. Had that been a problem, I believed redwag would have mentioned it.

Whenever I bought new rotors for the Jeeps I owned, I always had them turned before installing them because they were NEVER true. So even with new rotors, runout can be a problem.

X

[redwag]

What exactly is, or are the runout[s]?

[beastcivic]

Originally posted by redwag
Also, does anyone know what type of grease the manual specs for the rar side of the pad?

Use white lithium grease. Just make sure you don't get it on any of the friction surface or the rotors themselves.

[tan]

Originally posted by redwag
What exactly is, or are the runout[s]?

What's the easiest way to explain it....

it is a control mechanism, for surfaces measured about a axis, where the variation of the height of the surface cannot excced a certain amount.

In this case

Front: cannot exceed 0.0030 inches (0.075 mm)
Rear: " " 0.0028 inches (0.070 mm)

Also the minimum rotor thickness are

Front: 22 mm (fresh rotors are 24 mm thick)
Rear: 8.5 mm (fresh rotors are 10 mm thick)

the grease...Molykote AS880N, which is a silicone-based grease for the pad shims.


Looks like the safest (and the most expensive) bet is replace the rotors every time (just like what I have to do for my car)

[redwag]

Thanks....I'll be sure to have my buddy measure them at the shop...