Sand or Gravel Noise When Accelerating

[ThatWeirdDude]

New here, not sure if this is where it belongs

Just bought a 2011 4.0 4x4 with 133k miles. Drove real great initially but wanted to change the oil with 5W30 and transmission filter/fluid just to keep on top of it myself. Dropped the tranny pan the magnet looked like a caterpillar with metal shavings, fluid was dark purple and had some grime in the pan. No metal chunks or burnt smell. Now when I hit the throttle it sounds just like sand blowing in the a/c right behind the dash but once the engine is hot is sounds like a small amount of gravel in a can but only from about 1800 to 2000 rpm, hardly noticable with the a/c blowing though. Along with this there's been not a lot but a bit more vibration than I'm comforatble with just when idling. After some research looks like (worst case) it's timing chain tensioners which could've been hidden by last owner or seller using thicker oil or the transmission wasn't cared for enough throughout it's life, maybe a dying torque converter.

Could anyone point me in the right direction?

 

[franklin2]

If the gravel noise can be turned on and off with pressure on the throttle, that might be pre-ignition/pinging. What type of fuel are you running? If you are running 87 maybe you can try 89.

 

[ThatWeirdDude]

New to working on cars, is switching fuel more a way to diagnose? Have been running 87 so if I switch to 89 and the sounds stops should I change out the spark plugs, then switch back to 87 and look at fuel injection system or elsewhere like the exhaust if the 89 doesn't work?

 

[franklin2]

Yes, 89 would be a way to diagnose. If it helps it, you might have carbon build up in the top of the cylinders. Not sure of the latest way to clean that out. If it rattles and always suddenly clears up, even though you keep your foot in it, that would be the knock sensor working and detecting the pinging.

 

[ThatWeirdDude]

Yes, 89 would be a way to diagnose. If it helps it, you might have carbon build up in the top of the cylinders. Not sure of the latest way to clean that out. If it rattles and always suddenly clears up, even though you keep your foot in it, that would be the knock sensor working and detecting the pinging.

Thanks, tried out the 89, still have the pinging but idle is much smoother. Added a can of seafoam to the gas tank and ordered spark plugs. Going to clean MAF and change fuel filter also.

Doesn't clear up, gets worse as the engine gets hot and is consitent from 1800-2000 rpms only.

Realized this started after I changed the oil to motorcraft 5W30 and filter. Dipstick shows the level is barely a hair over full so I'll pump a small amount of it out.