Topic: Used Oil Analysis

[JohnnyO]

I've mentioned this before.  There are two here for the Jeep, an earlier one with plain old Pennzoil 5w-30 and a new one with Shell Rotella T-5 10w-30.  You will see that the wear metals parts per million (ppm) are lower with Rotella, the iron is MUCH lower, and it held its viscosity better.  Also there are spots for water and coolant in the oil, which are both 0.0, and you like to see 0.0.

http://72.35.72.219/~library/15563/Jeep_UOA_11_2011.pdf

[sharpxmen]

I've mentioned this before.  There are two here for the Jeep, an earlier one with plain old Pennzoil 5w-30 and a new one with Shell Rotella T-5 10w-30.  You will see that the wear metals parts per million (ppm) are lower with Rotella, the iron is MUCH lower, and it held its viscosity better.  Also there are spots for water and coolant in the oil, which are both 0.0, and you like to see 0.0.

http://72.35.72.219/~library/15563/Jeep_UOA_11_2011.pdf

very cool.

any reason for which "Make up oil added" says 4qts with Rotella and 2qts with Pennzoil? did you actually add 4 quarts in 3000 miles?

[JohnnyO]

any reason for which "Make up oil added" says 4qts with Rotella and 2qts with Pennzoil?

I don't know why.  PCV maybe?
 

did you actually add 4 quarts in 3000 miles?

Yes.

[chardrc]

isn't the oil capacity only 4 qrts? kinda makes the results irrelevant doesn't it since you cycled through the entire capacity of oil between changes?

[neale_rs]

There would be some mixing though.  I think the analysis company would know how to correct for these things.

[sharpxmen]

I don't know why.  PCV maybe?
 Yes.

too much, can't be PCV (or just PCV) - are you losing oil somehow? it is a lot though to add 1 gallon in 3000 miles.

[JohnnyO]

isn't the oil capacity only 4 qrts? kinda makes the results irrelevant doesn't it since you cycled through the entire capacity of oil between changes?

True.  I'm guessing that while the oil burns off, the wear metals will mostly stay behind.  Again, just an educated guess.  It is not leaking oil and does not smoke as far as I can tell.
The main thing is that after seeing a number of Jeep UOA's posted at BobIsTheOilGuy.com over the years, I've seen that Jeep motors tend to throw off a lot of iron.  Looking to minimize that, which the Rotella seems to do quite well.  Second, newer oils have less zinc which is an anti-wear additive because it contaminates catalytic converters when an engine burns oil.  However older flat-tappet engines need zinc and diesel-rated oils like Rotella have more that straight gas engine oil.  This is just me playing around with different stuff like I like to do.  Currently the Jeep has Max Life 10w-30 in it to see if it slows the oil consumption (it worked on my mother's Caddy) and I will get another UOA and see which it likes better.