Amsoil 5w30HDD / Kubota Diesel 1.6L / 191 hrs

[RJCorazza]

Most recent UOA for a 1.6L diesel tractor. Column 1 is 107h on oil, Column 2 is 191 hr on oil (508 hours total on engine). The initial fill was Amsoil 10w40 AMO, with 2qts make up oil for filter changes during last UOA interval. There were 3 qts make up oil for filter changes during this interval of Amsoil 5w30 HDD. Bypass filtration with TP filter (now MotorGuard). I was surprised to note the viscosity at 13.55 with using 5w30 HDD as the make up oil during this interval. Any comments?
107h 191h
Iron 2 9
Chromium 1 1
Lead 1 0
Copper 4 4
Tin 0 0
Aluminum 1 1
Nickel 0 0
Silver 0 0
Silicon 3 5
Boron 3 5
Sodium 0 2
Magnesium 38 36
Calcium 3410 3765
Barium 0 0
Phosphorus 910 1172
Zinc 1345 1361
Molybdenum 0 0
Titanium 0 0
Vandium 0 0
Potassium 0 0

Fuel %vol Vis100c 13.13 13.55
Water %vol 0.0 0.0
Soot/Solids %wt 0.3 0.09
Glycol Neg Neg
Nitr 13.0 14.0
Oxid 16.0 16.0
TBN 12.7 11.18

 

[Tommy]

Is 13.55 out of grade? At what point is it officially a 40 weight?

Was the Motorguard in use at the time of the first analysis?

 

[medic]

Yes, it is a very light 40 wt oil. I'm not exactly sure where the cut off is, but I would say anything 13 and over is a 40 wt oil.

I'm still not sure this slight thickening of Amsoil is a bad thing. Personally, in this application, I would rather see the oil thicken to a light 40 weight than thin into the 20 wt area.

It wasn't too long ago that most oils thinned out. A 5w-30 was a 20 wt. in no time at all, and I won't even mention what 10w-40's turned into. Amsoil thickens, what's worse?

I also won't go as far as saying Amsoil consistently thickens "out of grade". I ran ASL in my truck for 11k miles and it was @12.89 cst. I would bet there are good number of Amsoil UOA's here that haven't thickened out of grade. Also, I would bet that this oil starts out in the 11 to 12 range. So thickening to just over 13 isn't really a big deal.

 

[Pablo]

Was this a blend of oils...I'm confused?

Did you start with 10W-40 and add 5W-30??

Please clarify.

 

[RJCorazza]

"Was this a blend of oils...I'm confused?
Did you start with 10W-40 and add 5W-30??"

Yes, I started out with 6 qts of 10w40 AMO in the engine. The first UOA at 107 hrs was all 10w40 (2 qts make up oil) and it thinned to 13.13. Immediately after the first UOA I started using 5w30 HDD for the make up oil (3 qts added for filter changes) and the current viscosity is 13.55 with a blend of 10w40 & 5w30. The blend should be about 50/50. At any rate, I expected the vis. to be lower. The 10w40 was thinning, now with the addition of 5w30 it is thickening? Not overly concerned, just confused.

 

[RJCorazza]

"Was the Motorguard in use at the time of the first analysis?"

The same filter was in use during both periods... it was a Frantz TP filter. I replaced it with the Motorguard TP after the second sample.

 

[Pablo]

OK Gotcha (sorry) - I guess the oil may have thickened just a hair....but not totally out of whack for that blend. I certainly can't say your brew thickened out of grade!

As for the real interest (your analysis) the oil and your tractor look great! 191 hours is a bit of use.

 

[mountravlr]

Amsoil seems to thicken out-of-grade consistently, as seen among the various UOA's posted at BITOG. Everything looks fine otherwise for your engine, especially the TBN.