i want to know when is the timing belt need to be changed
The 3.5 V6 has a timing chain and not a belt so no special service required.
Nissan has used a cam-chain on all their 4 cylinders and V6s for years. The cam-chain is under the front engine cover and runs in oil at all times. Theoretically, they should last the life of the engine ... but Nissan has had a few issues with their cam-chains and the tensioners/chain guides on a few of their engines.
With altimas have this problem with there cam chain and the tensioners/chain guides
Looking for a Used Altima in your area?
CarGurus has 76,224 nationwide Altima listings starting at $900.
Search Nissan Altima Questions
Nissan Altima Experts
Related Models For Sale
Used Cars For Sale