Hey Afshin. If you have low miles on your 500, You can wait on the timing chain. I'd replace the rail and chain and tensioner about 85K. If you have like 50 or 60K. Your ok still. Truth is our damn 500's get soo hot. Its not a bad idea changing out the hoses. I havn't change the rears. I did the fronts, at 84K with a new waterpump,waterpump bypass,upper and lower rad hoses.
Also For all you 500 guys out there. There is the braided return line from the hydraulic revervoir,they get hot and crack I rec to replace them. Also the hydraulic braided return hose from p/s pump to the reservoir line.


Well thats about it right now.


Guido

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500E Sold
2006 Mini Cooper S
Modified,pulley,injectors,suspension
2009 E350 Sport AMG package