Indirect way to check for engine sludge?

[cf99]

If you change your oil (I've always used Valvoline conventional dino) and filter, and 150 miles later the oil on the dipstick is still crystal clear, do you think that indirectly verifies you have no sludge problem?

You'd think that after 150 miles of operation, if you had sludge, it would have discolored/darkened the oil.

It probably doesn't work the other way around though. In other words, if your oil IS discolored after 150 miles, it doesn't necessarily mean you have a sludge problem. Could be due to something else.

Any thoughts?

[Chris Crash]

Only way to verify is pop the valve cover and check. It's really not that hard.

[Safari Wagon]

I guess that may give you some indication.... I don't think you can put a number on it though - like 150. My oil doesn't look black after a couple thousand miles, but what is black to me may not be black to you.

You can also take the oil filler cap off and reach under the cover with your finder and slide it along to see if you can pull up any stuff.

[fenixus]

well, simple "test" is to drain oil after 500 miles and see what color it is. if it was dino/conventional and turned black there is a good chance some sludge started forming already and kills the oil properties prematurely (it should be good as new for at least 1,200 miles / 1 month or so) or engine runs too hot (cooks oil) or too rich or there is some emission component failing and making things dirtier than usual or so.

I know only 1 non-intrusive way to look for sludge signs. remove the oil filter (or do it while draining oil), take the flash light and look through the oil filter opening and check if you can actually see any metal shiny parts down there in crank case. if not then your chances for having a dirty engine are growing.

[RNMCGUIRE]

Well I can verify that synthetic oil will not show much after 500 miles. I recently realized that I have a terrible sludge problem in my wife's car (95 1MZFE)that we bought 6 months ago. I'm running Mobile 1 and just changed the oil 500 miles ago. My dipstick still looks pretty good.

[Stillrunning]

Originally Posted by RNMCGUIRE

I recently realized that I have a terrible sludge problem in my wife's car (95 1MZFE)that we bought 6 months ago.

I've used this with good success.

[Pvt-Public]

The only way to really check for sludge is to open things up, ie. valve cover, oil pan. Just looking at the color of the oil, or looking at one little spot visible through the oil filler or pan plug won't really tell you much unless the problem is so out of control there is no fixing it.

[mail2_jb]

i noticed oil darkening within 200 miles after an oil change (conventional oil) on my gen 4 camry. However when I removed the valve cover for gasket replacement, the engine is free of any sludge. So I am not sure the oil darkening will give an accurate picture of sludge. Like fenixus said, check the oil filter area or pull the valve cover and spend like 20$ to get a new gasket and put it back together

[Pauloil]

why not just drive the car and change the oil like you always do?

[Jimnist]

If you really want to, you can always shove a boroscope into the sump drain hole? That'll check the bottom end, but for the top, (as already mentioned) you'll need to take the valve cover off. There's usually a plate below the oil fill point stopping oil from splashing all over the place.