Brake rotor minimum thickness - 2007 Hyundai Sonata 2.0

Each brake rotor has the minimum thickness marked on the rotor. Keep in mind also that the comparative thickness of each side of a vented rotor must be considered. Even if the overall thickness is greater than the minimum, each side must be within .040" (1mm) of the other.

The minimum rotor thickness is normally cast into the rotor. You will find it printed either on the outside hat section of the rotor or on the very top edge section of the rotor.
There are some example pictures here

http://forums.justcommodores.com.au/dba-brakes/249789-dba-tech-talk-when-your-rotors-undersize-rotor-minimum-thickness.html

Hello there
From a kind chap on this page
http://buickforums.com/forums/threads/18395-Service-limits-for-brake-rotors

For a 2000 Buick LeSabre

FRONT BRAKE ROTORS:
Discard Thickness30.7 mm (1.209 in.)
Lateral Runout (New)0.06 mm (0.002 in.)
Minimum Thickness after Refinish31.08 mm (1.224 in.)
Rotor Diameter 15 inch Wheels (New)278.0 mm (10.9 in.)
Rotor Diameter 16 inch Wheels (New)303.0 mm (11.9 in.)
Rotor Thickness (New)32.20 mm (1.267 in.)
Thickness Variation (New)0.025 mm (0.001 in.)

Rear Brakes JC5/JH5 Utility Only
Rotor Discard Thickness* .............................. 28.50 mm (1.122 inch)
Rotor Minimum Allowable Thickness After Refinish ....... 29.0 mm (1.142 inch)
Rotor Thickness-new .................................... 30.0 mm (1.181 inch)
Rotor Maximum Allowable Lateral Runout ................. 0.05 mm (0.002 inch)
Rotor Maximum Allowable Scoring ........................ 1.50 mm (0.059 inch)
Rotor Maximum Allowable Thickness Variation ........... 0.025 mm (0.001 inch)

Rear Brakes JH6
Rotor Discard Thickness * ............................. 27.50 mm (1.082 inch)
Rotor Minimum Allowable Thickness After Refinish ....... 28.0 mm (1.102 inch)
Rotor Thickness-new .................................... 29.0 mm (1.141 inch)
Rotor Maximum Allowable Lateral Runout ................. 0.05 mm (0.002 inch)
Rotor Maximum Allowable Scoring ........................ 1.50 mm (0.059 inch)
Rotor Maximum Allowable Thickness Variation ........... 0.025 mm (0.001 inch)

rotor thickness is cast into the rotor but if you cannot find it then contact a brake shop as they have the minimum measurements for all vehicles .

lordFord's answer was arrogant and absolutely useless. Brake rotor thickness specifications are dependent upon the Year/Make/Model of the vehicle, it has nothing to do with your "state/province" or "common sense." Most brake rotors have the minimum thickness spec. stamped on the rotor itself. The service department of the dealership for whatever brand of vehicle you have, will be able to provide the spec. to you as well. A visual inspection may point to obvious signs such as scoring, cracks or pitting, and a vibration when applying the brakes, could be a warped rotor.

All are different, on the back side of the brake rotor , will have a stamp with (MIN) and some number after it the will be the minimum spec thickness for the brake rotor.

your brake rotors are warped, if your vehicle is equipped with rear drum brakes have them cleaned and adjusted to keep your front brakes from working too hard and becoming warped, also replacing the front rotors is better than resurfacing them because after bieng resurfaced they are thinner and are more prone to becoming warped again

depends on your state/province and common sense. if you must ask this question, replace the rotors.

there is many kind of brake system of ur truck here i will send u everything about the brake and i hope its help

Rear Brakes JC3

Rotor Discard Thickness* 18.50 mm/0.728 in Rotor Minimum Allowable Thickness After Refinish 19.0 mm/0.748 in Rotor Thickness (new) 20.0 mm/0.787 in Rotor Maximum Allowable Lateral Runout 0.05 mm/0.002 in Rotor Maximum Allowable Scoring 1.50 mm/0.059 in Rotor Maximum Allowable Thickness Variation 0.025 mm/0.001 in
Rear Brakes JC4

Rotor Discard Thickness* 28.50 mm/1.122 in Rotor Minimum Allowable Thickness After Refinish 29.0 mm/1.142 in Rotor Thickness (new) 30.0 mm/1.181 in Rotor Maximum Allowable Lateral Runout 0.05 mm/0.002 in Rotor Maximum Allowable Scoring1 .50 mm/0.059 in Rotor Maximum Allowable Thickness Variation 0.025 mm/0.001 in
Rear Brakes JH2

Rotor Discard Thickness* 28.50 mm/1.122 in Rotor Minimum Allowable Thickness After Refinish 29.0 mm/1.142 in Rotor Thickness (new) 30.0 mm/1.181 in Rotor Maximum Allowable Lateral Runout 0.05 mm/0.002 in Rotor Maximum Allowable Scoring 1.50 mm/0.059 in Rotor Maximum Allowable Thickness Variation 0.025 mm/0.001 in
Rear Brakes JH6

Rotor Discard Thickness* 27.50 mm/1.082 in Rotor Minimum Allowable Thickness After Refinish 28.0 mm/1.102 in Rotor Thickness (new) 29.0 mm/1.141 in Rotor Maximum Allowable Lateral Runout 0.05 mm/0.002 in Rotor Maximum Allowable Scoring 1.50 mm/0.059 in Rotor Maximum Allowable Thickness Variation 0.025 mm/0.001 in
Rear Brakes JH7

Rotor Discard Thickness* 28.5 mm/1.122 in Rotor Minimum Allowable Thickness After Refinish 29.0 mm/1.142 in Rotor Thickness (new) 30.0 mm/1.181 in Rotor Maximum Allowable Lateral Runout 0.05 mm/0.002 in Rotor Maximum Allowable Scoring 1.50 mm/0.059 in Rotor Maximum Allowable Thickness Variation 0.025 mm/0.001 in
* All brake rotors have a discard dimension cast into them. Replace any rotor that does not meet this Specification. After refinishing the rotor, replace any rotor that does not meet the minimum or discard thickness specifications.