I have bought the OEM service manuals for every car I have ever owned (except the Porsche, because Porsche wants an immense amount of money for their manual, if you can believe that). I have worked from Nissan manuals in the past and found that they are very helpful in explaining virtually every aspect of most procedures.
I recommend to anyone with any mechanical ability, an few tools, and the intention of keeping your vehicle for a while (i.e. more than the term of your loan) to purchase the service manual.
If you think about it, ONE use of the manual with your elbow grease would recover the cost of the manual just in labor savings from an average,out of warranty, dealer service visit.

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