N62 engines do have timing chain guide issues but they are far less common than M62 failures. Say 20 M62 failures for every 1 N62 failure. N62s do have timing issues if you run them low on engine oil. We've seen several N62s jump timing and run like crap when they are run low on oil. Guides should not be an issue on an N62 provided you are keeping up with your oil change intervals using a quality oil. The N62s we do see with failed guides have been vehicles with sludged up engine internals. The guides become hard, brittle and begin to disintegrate when the oil itself begins to degrade. These are also the vehicles that we commonly see exhibiting valve stem seal issues. We have seen N62s in excess of 200k miles that don't smoke in the slightest, these are the vehicles that maintain a 5k oil change interval with a high quality synthetic and have nice golden internals when you do have to open them up.

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2004 BMW X5 4.4i-Sports Package-Premium-140,000 Miles