Hi all,

I'm new to the forum so let me know if I put this in the wrong place or if i missed a post of the same issue.

I have a remanufactured 4.0 in with about 60,000km on it. Straight from the shop there was a bit of a rattle at idle when the truck was warm. It's gotten a bit louder and I'm seeing a little bit of metal at oil changes. The noise goes away as soon as its over about 900rpm, and isn't there are startup. I figure it must be a loose chain, maybe a tensioner not doing it's job from low oil pressure as the oil warms up. I think the remanned engines come with new oil pumps, I've checked the oil pickup and all looks good and clean, next I was going to change the tensioners. Any advice on how to diagnose this would be great. I'm pretty rattled about paying way too much for this new engine and install...

 

I would change the two long chain tensioners, motorcraft or cloyes brand only

Make sure to prime them, and be careful not to cross thread the front drivers side tensioner, easy to do

 

Consider dropping the OilPan to inspect for TimingGuide schrapnel & clean the OilPumpSuctionScreen while you're there.
Relatively easy+cheap to do; requires new Oil+Filter+PanGasket.
If pieces are found, their shape possibly can tell you what part has broken, compared to pictures of new TimingParts.