Loud engine tapping noise at idle

[TheJMan]

Today I drove my brother's Explorer and I noticed that it makes a noticeable "tapping" sound at the speed of the engine. It has always done this, but for some reason it seemed louder today. The only factor I can imagine is that I changed the oil. It had Pennzoil 5W-30 with a Bosch filter and now it has Maxlife 10W-30 with a Motorcraft filter.

Any ideas? It's a 1993 4.0 with 91,500 miles.

 

[Heavymentill]

Sounds like worn rocker arms. Contact http://www.deltacam.com/ They offer upgraded rocker arms and pushrods.

 

[TheJMan]

Oh, I forgot to mention that it is only noticeable at idle after the engine has warmed up to temperature.

Though I do appreciate your response, can the rocker arms really be worn out with less than 100k miles? Maintenance on this engine has always been done every 3,000 miles and this vehicle has been in our family since 1993.

 

[TPLYNCH]

10-30 vs 5-30 can make a difference, but ususally only causes noise on startup. Have you rechecked the oil level?

 

[TheJMan]

The oil level is right on the money. Before I changed the oil, I noticed that it was 1/2 quart low.

 

[karl_burns]

Is it from the top or bottom?
I've been getting a tapping sound from the bottom. Sounds like it's in either my oil pan or the transmission (5 speed). almost like there's apiece of metal rattling around. You basically can't hear it from above the engine. Same thing?
Karl

 

[TheJMan]

It sounds like it is coming from the driver's side, top of the engine. Maybe a worn rockerarm is a possibility after all. The engine does run great, however, and no engine components have ever needed to be serviced in the 12 years the Explorer has been in our family.

 

[Heavymentill]

If you going to replace the rocker arms this is your best bet. They are from delta cam. Cheeper to get them off ebay. CLICK

 

[TheJMan]

Thanks for your help.

 

[98xlt2wd]

10-30 vs 5-30 can make a difference, but ususally only causes noise on startup. Have you rechecked the oil level?

Which one makes noise on start up?

 

[TheJMan]

It's not the startup, it's when the engine is hot that it is the loudest. 10W-30 seems to be making more noise.