If your used truck is Nissan certified, then they often give you an extended warranty of up to 100,000 miles or 72 months. But I would get it checked anyway. I bought my X used and at 45k, the manifold was already cracked. Dealer replaced it in one day free of charge. Get it checked out now and when you hit 90k, you can go back and get another one replaced before your warranty expires.

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