(Check Thickness And Condition Of Brake Disks - AR42.10-P-0120FR)

Model 257 

Modification notes

04.07.2018

Measure thickness of brake disks on front and rear axles with vernier caliper, added

Operation step 2

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	Risk of injury.  Skin or eye injuries may result when handling hot or glowing objects.	Wear protective gloves, protective clothing and safety glasses, if necessary.	AS00.00-Z-0002-01A
	Notes on handling, transport and storage of composite brake disks		AH42.10-P-9406-12LF
	Remove
1	Remove wheel and tire assemblies.		AR40.10-P-1102A
	Measure
2	Measure thickness of brake disks (1) on front and rear axles with vernier caliper.	Model 257.314/318/348 Model 257.320/321/323/350/351 Model 257.358/359/361 Brake disk thickness	*BE42.10-P-1001-09CA
		Model 257.314 Model 257.318/348/350/351 except code P31 (AMG Line exterior) except code U29 (Brake system with larger brake disks on the front axle) Model 257.318/348/350/351 with code P31 (AMG Line exterior) Model 257.318/348/350/351 with code U29 (Brake system with larger brake disks on the front axle) Model 257.320/321/323/358/359/361 Brake disk thickness	*BE42.10-P-1001-08EA
		Caliper gauge If the wear limit has been exceeded or will be exceeded before the next brakepad change. ↓	Fig 1
		Replace brake disks (1).	AR42.10-P-0220FR
	Check
3	Check brake disks (1) on front and rear axle for corrosion, score marks, cracks and chippings.	For perforated brake disks or those provided with sunk holes (1) assess the crack length (x) including the bore diameter. Model 257.314/318/348 Model 257.320/321/323/350/351 Model 257.358/359/361Check brake disks	*BE42.10-P-1002-09CA
		Model 257.314 Model 257.318/348/350/351 except code P31 (AMG Line exterior) except code U29 (Brake system with larger brake disks on the front axle) Model 257.318/348/350/351 with code P31 (AMG Line exterior) Model 257.318/348/350/351 with code U29 (Brake system with larger brake disks on the front axle) Model 257.320/321/323/358/359/361 Check brake disks	*BE42.10-P-1002-08EA
		In the event of a problem, ↓ Replace brake disks (1).	AR42.10-P-0220FR
	Install
4	Attach wheel and tire assemblies.		AR40.10-P-1102A

Check values for front axle brake disks

Number	Designation			Model 257.314 Model 257.318/348/350/351 except code P31 (AMG Line exterior) except code U29 (Brake system with larger brake disks on the front axle)	Model 257.318/348/350/351 with code P31 (AMG Line exterior) Model 257.318/348/350/351 with code U29 (Brake system with larger brake disks on the front axle) Model 257.320/321/323/35 8/359/361
BE42.10-P-1001-08EA	Brake disk thickness	New	mm	32	36
		Wear limit	mm	29, 4	34

Check values for rear axle brake disks

Number	Designation			Model 257.314/318/348	Model 257.320/321/323/350/351
BE42.10-P-1001-09CA	Brake disk thickness	New	mm	22	24
		Wear limit	mm	19, 4	21, 4

Check values for rear axle brake disks

Number	Designation			Model 257.358/359/361
BE42.10-P-1001-09CA	Brake disk thickness	New	mm	26
		Wear limit	mm	23, 4

Check values for front axle brake disks

Number	Designation				Model 257.314 Model 257.318/348/350/351 except code P31 (AMG Line exterior) except code U29 (Brake system with larger brake disks on the front axle)	Model 257.318/348/350/351 with code P31 (AMG Line exterior) Model 257.318/348/350/351 with code U29 (Brake system with larger brake disks on the front axle) Model 257.320/321/323/35 8/359/361
BE42.10-P-1002-08EA	Check brake disks	Crack length	Dimension "x"	mm	< 25	< 25
		Crack depth		mm	< 0, 5	< 0, 5

Check values for rear axle brake disks

Number	Designation				Model 257.314/318/348	Model 257.320/321/323/350/351
BE42.10-P-1002-09CA	Check brake disks	Crack length	Dimension "x"	mm	< 25	< 25
		Crack depth		mm	< 0, 5	< 0, 5

Check values for rear axle brake disks

Number	Designation				Model 257.358/359/361
BE42.10-P-1002-09CA	Check brake disks	Crack length	Dimension "x"	mm	< 25
		Crack depth		mm	< 0, 5

Fig 1: Identifying Caliper Gauge (140 589 00 19 00)

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