3.0 knock

[katfishking]

when i have my ranger in too high of a gear the 3.0 makes sorta a knocking/thcking sound. is it just because im in a high gear or need a rebuild?

 

[Sasquatch_Ryda]

It is 'pinging' or pre ignition.

The 3.0L have a bad habit of carboning up the combustion chambers easily leading to 'hot spots' in the cylinder heads. When the engine is lugged down like that it will cause that rattling/knocking sound you are hearing.

Running some good combustion chamber cleaner through the engine via a vacuum line and driving it like you stole it can usually help to clear it up. If it is bad enough, the only way to get rid of it is to pull the heads and scrape all of the carbon deposits off of the heads.

Best thing to keep this from happening is to rev the piss out of it. It will be quite happy to spin 2500-3000 rpm all day long. Don't drive in town in 4th, keep it in 3rd to keep the revs up. I shift mine at 3000rpm, leave it in 3rd in town and don't use overdrive a lot on the highways.

 

[cush]

mine has this kinda strange rattle sound usually in 3rd at higher rpms or when i'm headed up a steep hill like the grapevine in southern cali. but it sound like either pennies rattling or a loose bolt rattling. thing is though that its not my change and i cant find anything. it doesnt do it all the time so i dot worry too much about it.

 

[Sasquatch_Ryda]

^^^ that is classic pinging.

 

[cush]

sweet! so my work sells some products from bg, i dont know if you've heard of bg but it supposed to be really good stuff and its not sold in stores. we sell the fuel injection system cleaner, air intake system cleaner and bg's 44k. think that might help?