jdforsythe

It just figures......getting ready for the big trip to Virginia, I decide to change the oil. No big deal, done it a thousand times. I used a standard NAPA 10w40 oil and NAPA filter. I drive it around to make sure there are no leaks and now I am getting a slight knock from the valve area. I used multi-weight because of the hydraulic lifters. Is there any chance changing from 10w30 to 10w40 could cause this?

Volcom66

first off why did you use napa's crappy oil! but anyways i wouldnt think 10w30 to 10w40 would do so. I dont put any weight higher then 30 in any car.

Derf00

actually, why wouldn't you put multi-weight in a car? Straigh oil is arguably worse that multi-weight in any vehicle for many reasons including the increased friction caused by straight weight upon start up.

However, you do bring up a good point.

JDforsyth, does the knocking occur after warmup? 10w-40 being thicker than 10w-30 after it's been warmed up may be causing the oil not circulate as readily as the slightly thinner 10w-30. This could be due to restricted oil passages from dirt or just buildup in the passages.

Soaring

Sounds like you are hearing things that aren't there. Just drive it, and don't listen to the little ticks from an old engine.

Scott H.

Could also be a piece of carbon/gunk has broken free and is partially plugging up a lifter. There are some pretty aggressive cleaners out there, but you run the risk of actually making it worse, depending on how much build up is inside, and how good of a job the engine flush/decarbonizer works.

Did your oil pressure change after the oil change. If it's higher, try putting a cheap filter on and see if the "clicking" goes away and the pressure drops.

BTW: Climate should be the determining factor to oil viscosity, and multi-viscosity oil is the way to go. The closer the numbers the better. I run a 10W-30 as my climate doesn't drop much below freezing nor get higher than 110F, and I don't drive the car much if it's colder than 40F or hotter than 90F.
Make sure your oil level is *between* add and full. Too low or too high will cause cavitation that can starve a lifter.

HTH,

Scott

Gun Jam

mine doesn’t click or tick

Napa oil is Valvoline oil just in a different carton and its not crap.

10-40 should boost oil pressure a bit but I wouldn’t think it would restrict it to the point where it doesn’t flow enough. Oil pressure actually drops off after the engine warms up to operating temp as well.

Perhaps taking off the valve cover and watching the volume of oil, if it spills out on the headers and smokes before you can get out of the driver's seat to have a look then your good to go!

Thats my only suggestion
Gun

69FECoupe

10/40 should work just fine and as Gun Jam has mentioned, NAPA oil is Valvoline and their filters are good quality also. I use them both in my shop.

SuperHoss

Because of the strict rules that oil makers must follow and the standards that they must comply to; the best motor oil out there is not much better than the worst...everyone has to pass the same inspection. Just run a brand that you are comfortable with, after all, I've heard horror strories about every kind of oil and oil filter out there...so I just pick the one I like.