93 nissan D21 rattles at higher rpm

[trucknewbie89]

when i start the truck, a rattling noise comes from the engine. i shift it into neutral and it disappears. it also rattles at higher rpm's when i'm about to shift into a higher gear. it almost sounds like a grinding noise. is is the timing chain? it has 91k on it and heard that they should be replaced every 100k.

[RT22]

probably the timing chain guides, they are plastic and break and make noise

[trucknewbie89]

how urgent of a repair is this?

[Rev_D21]

I wouldn't drive it too long like that but it's not a 'truck down' emergency. If you let it go too long you'll be replacing the timing cover.