I posted this problem once before, but I messed it up somehow. I made a new recording (directly under the engine, where it seems to be loudest) http://www.resonantecho.com/noise.mp3; please listen and give me your opinions.

I lost count on how many different oil additives that I have tried (with different oil changes), but I tried one yesterday called "ZMAX Micro Lubricant", which has dramatically lessened the sound to a fraction of what it once was. As this is the first time trying this, I dont know if the sound will return once I change the oil out again, or if I will need to purchase this every oil change ($19.99 a pop).

Thanks.

 

lifter

 

i must agree,

 

i work with a guy who has a 97 dakota pickup with almost 300K miles and he swears by lucas oil additives, he has a similar problem and says that this has kept things quiet for almost 70k

 

Lifters & Pushrods were replaced about 30K miles ago. No change in noise.

 

It's been making this noise for over "30K?" For over 30,000 miles and how many years?

Overhead cam engines make that noise when the oil level gets low. The lash adjusters in the tip of the rocker arms aren't getting enough lubrication.

These engines don't have lash adjusters, so it's obviously not that. But it definitely seems valvetrain related. And if it isn't the lifters or pushrods, then perhaps it's a rocker arm/valve lash adjustment problem.

 

I thing it's saying:"treefitty-treefitty-treefitty-treefitty" That'll fix it!

 

It almost sounded like there was a small exhaust leak in there too, did I hear that right?

 

I agree, I think I hear exhaust as well.