Please someone help. I have a `92, 7.3 diesel and it has 142,000 miles on it. All has been well, but about three days ago (after an oil change, used Penzoil 10-40, never have I used it before) I heard a strange loud clicking noise coming from the engine compartment. It sounds like either a broken valve spring or a collapsed lifter type clicking. Steady and loud and increases with the engines' rpm. Any idea? Any way to check/delete possible problems, short of tearing it down? Thanks.

 

Change the oil back to the wieght you used before. See if it goes away. 10W/40? Is that OK for that engine?

 

Did you use a different brand of oil filter too? Please tell us you didn't use a Fram:-X23

 

I agree with Monsta on this. I would switch back to the motor oil that you used before the problem occurred and try that. I am sure that you know this, however, I will mention it anyway. Make sure that the first letter of the API Service Rating is "C". The first letter indicates vehicle fuel type that the oil is designed for.
"C" is intended for diesel engines (i.e. CH-4).
"S" is intended for gasoline engines (i.e. SH).
The second letter indicates the quality level of the motor oil. The higher the letter the more advanced the oil and more protection it offers. Example: An CH-4 oil can be used in any diesel engine requiring a lower protection such as CE, CF-4 or CG-4 oil. API
"CI-4 is the newest classification of modern, electronically controled, low emission diesel engines.
The three motor oils listed below are the most widely used in the diesel engine community. Each has been tested and proven with millions of miles/hours on them. Each one is good, it boils down to personal preference.
Chevron "Delo 400" Heavy Duty Motor Oil
Shell "Rotella T" Heavy Duty Motor Oil
Mobil "Delvac 1300" Heavy Duty Motor Oil
As far as the SAE goes, it depends on the climate that you operate in. Multigrades or straight weight.

 

Unless you poured the oil in the radiator (that's a joke) I can't imagine why the oil change would cause what you described. It is possible that you've got an oil filter that is for some reason restricting the flow. The only way to know for sure is with an oil pressure gauge or you could replace the filter with another to see if the problem goes away (if you still have the old one, put it back on and see what happens). But even if oil flow were the problem, you wouldn't have a noise that sounds like one collapsed lifter, they would all collapse. I think you've got a problem that is independent of the oil change. Determine which side it is coming from and remove the valve cover on that side. If it sounds like a collapsed lifter then there is probably something wrong with the valve actuation mechanism on the side the noise is coming from -- probably a broken rocker arm. It would be great if every time we had a problem we could just go to a site on the Internet and have our questions answered correctly but it has been my experience that you're going to have to break out the tool box and do some wrenching to locate the problem.

 

i wouldn't be using 10w40
I have and always will stick to the 15w40
the owners manual even recomends it.