I believe my '03 Edge with all of 49,500 miles has the SOHC Timing Chain Rattle Heard during freeway acceleration 2600-3000+ rpm run to 60 when the engine is still on the cool end of the scale. Backing out of the throttle to a slower acceleration quiets things down immediately.

This brings up the question: If left unchecked, will this eventually result in a catastrophic engine failure? – Will there eventually be enough slack in the chain to start skipping teeth on the sprockets to the point that valves start hitting pistons?

Or is this just an annoying noise issue that can be somewhat mitigated by higher quality oil?

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2003 Edge 4x4 Sonic Blue 4.0 SOHC, Auto, 4.10 LSD, 4-door Supercab

I was told recently if it starts to go then finally goes you're screwed. Get it looked at right away. I'd hate to see that go on such a nice truck man. Do you have anytype of extended warranty? If not look into it and maybe it will be cheaper than paying for a ton of work

you'll be fine, what actually happens is the guides break and it allows the chain to "flap" around a little more and make some noise.. long term issues? none as of yet.. it all depends on how long you can handle the sound.

mine's been at it for the last 5k miles.

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2001 Ford Ranger Supercab (4dr), Oxford White, 4.0 Sohc, 4x4, Manual trans (hurst equipped), 4:10's, 3" body lift.

No extended warranty, I'm the 3rd owner and I just might be crazy enough to tackle this on my own as long as it's just replacing guides and tensioners. That in itself seems fairly straightforward. I can't imagine the chains or sprockets being in any need of replacement at this low mileage.

A guy on explorerforum did the rear chain by dropping the transmission and pulling the flywheel…which is good to know because I don't have the space to pull the engine.

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2003 Edge 4x4 Sonic Blue 4.0 SOHC, Auto, 4.10 LSD, 4-door Supercab

Mine does it as well. Been doing it for a while now. Very common on these 4.0s from what I hear.

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02 Ranger XLT 4x4 Off Road, 4.0L SOHC, Automatic, 8.8 4.10 LS, Super-Cab, 3" Body Lift, 33x12.5x15 BFG All Terrains on 15x8 M/T Classic IIs, 5K 55w Heads, 5K 35w fogs, custom front skid plate, various other goodies.