98 5.0L AWD Knock (Again)

[ericautopart]

I've read through a good 20 posts about engine knocks but non of them seem to replicate mine. 115,x.. miles on a 1998 5.0 XLT AWD. I aquired the truck @ 98,000 so I don't know it's history before me but I've had oil changed w/ 10 30 every 3000 since. Anyway..engine has a very faint knock at idle. Doesn't get louder upon acceleration or just revving the engine. Only at idle. Oil is clean, runs like new, drives perfect. I know I've heard "this is normal" for the 5.0, etc. My 4.6 in the expedition used to knock at start up but went away when it warmed up. This is always there but never gets louder..idea or two? Truck cost me $300 bucks so I'm not interested in dumping a ton of money into her. It's also my work truck so it's driven M-F but I have 2 other cars.

 

[my98nnj]

Oil is clean, runs like new, drives perfect. I know I've heard "this is normal" for the 5.0, etc.

Just drive it, for 300 bucks if the engine does quit on you down the road toss a used motor in and continue to drive it. Your still ahead of the game.

 

[ericautopart]

Just drive it, for 300 bucks if the engine does quit on you down the road toss a used motor in and continue to drive it. Your still ahead of the game.

My thoughts exactly but I'd still like an idea if someone knew of the issue..

 

[Turdle]

Try another oil filter. I am serious.

You may want to get an actual oil pressure reading before replacing the filter and after. The dummy gauge in the cluster reads "normal" with only 6psi, so you will need a good sender and gauge.

 

[eXcali]

If your still getting some knocking after your filter change/pressure check, try some engine honey such as Lucas Oil added to your oil. If this quiets it down I would do a flush and switch to full synthetic on your next oil change as it will coat better and flush most of the build up out.

 

[BrianDye]

Is that Lucas Honey stuff good? My 92 does a ticking/knocking sound when its cold, but once I take off, or run it for 5 mins it goes away....

 

[eXcali]

Is that Lucas Honey stuff good? My 92 does a ticking/knocking sound when its cold, but once I take off, or run it for 5 mins it goes away....

Yep it's great stuff. I have used it for years, it's excellent for coating noisy parts. On my 460 I had huge problems with tons of noise coming from the lifters. I pulled the motor cleaned it all up and drenched them with this stuff, after putting it all back together there's no more noise. Only problem is the oil pump is shot now, I should have changed it then but I didn't....

In general preventative maintence I was adding about 1/4 to 1/2 quart of the lucas each oil change.