General remarks
Vehicles use parts with metric threads in accordance with ISO standards.
Nuts, bolts and screws with damaged threads must be replaced with new ones. Driving a damaged thread with a die or tap will loosen the thread and increase the gap in the thread. Threading is not recommended.
If a bolt is being replaced, then it must be ensured that the new bolt has a strength index not lower than the one being replaced. Cotter pin nuts must not be loosened to align the cotter pin holes. An exception is the case when this is provided for by the adjustment instruction.
Do not allow oil or grease to enter tapped blind holes. When tightening a bolt with a small thread clearance, the oil that has entered the hole is compressed and can lead to the destruction of the housing.
Always tighten the bolt or nut to the recommended torque. Damaged or rusty threads will increase the thread tightening torque.
To check the bolt torque, loosen it a quarter of a turn and then retighten it to the correct value.
Lubricate the threads with a little oil before tightening. Exceptions are threaded parts lubricated with sealant and self-locking nuts.
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