I have just purchased my 1998 Chevy Silverado c/k 1500 fleetside a couple weeks ago and now the engine is making a noise. It almost sounds like a valve knock, but it does not do it at idle. It's a really loud noise that sounds like a knock. I drove it pretty hard today becasue I just put a new aftermarket air filter on it. The truck has 115,000 miles and it ran like brand new and still does accept for this noise? Can anyone help me? Thanks!

 

Is it a knock or a tap? Try reving it up from under the hood and see if you can tell where it is coming from. My LT1 in my Camaro has a valve tap but I wouldn't say it's much of a problem. It's well oiled and hasn't gotten any worse so I'm not too concerned. Argon may have a different take though. I don't know if it's actually a big problem or not but he'd know.

 

its hard to know without hearing it..

does it sound like its up top?(valve area?)..or deep and hollow?

 

are there aluminum heads on a '98? My '01 sounded like the lifters were dry. I was told aluminum carries engine noise.