Hydrogen build-up in the rear brakes could impact stopping performance.
Mercedes-Benz Australia has issued a recall for certain GLE and GLS SUVs sold during 2018 over concerns the rear axle's brakes could be compromised.
The company reports hydrogen may become embedded in the material of the pistons "of a certain batch of brake calipers", which could then enter the hydraulic components of the rear axle and "cause compressibility there".
If the condition occurs, braking power on the rear axle may be impaired, and brake pedal travel could be extended. Mercedes-Benz says this could increase the risk of an accident.
Owners are advised to contact their local Mercedes-Benz dealer to arrange the repair of their vehicle, free of charge.