2004 Crown Vic, RLI BioSyn 5W20, 4000 miles

Not open for further replies.
Aug 15, 2006
Central Washington
55,200 miles on unit at time of sample. Oil in use 7 months. Mosly used back and forth to work but did mix in some highway driving here and there. Really thought it would do better, but then again, it had to deal with leftovers from the schaeffer run previous (TAN=4!) so I cant be too hard on it. I have one more run left in the bucket so we shall see. Going 5k miles the current fill, but itll be part cheating. Im going down to Vegas in December and that will put 2k miles on it quick and all highway. Previous UOA
Iron		18
Copper		9
Tin		0
Lead		1
Chromium	2
Nickel		0
Aluminium	2
Titanium	0
Silver		0

Calcium		1946
Magnesium	20
Zinc		936
Phosphorus 	673
Barium		0
Molybdenum	28
Antimony	209

Silicon		14
Sodium		16
Boron		8
Potassium	0
Vanadium	0

Visc40C		39.5cSt
Visc100C	8.0cSt
TAN		2.52
Flash		325F
Oxidation	77
Nitration	12
KF Water	381
TBN		2.0
Fuel		1.25
Sulfate		110
Lab is Dyson
Not a bad UOA. I really wonder how antimony compares with boron or moly. I have to do some research. Expensive oil for 4k runs but I know how it is. I am a serial changer. Thanks for posting
Not bad results, considering the service. But like chubbs1 said, expensive oil for such a run - MC 5W-20 would probably deliver similar results for about 1/3rd the cost!
There has to be another, cheaper oil for your application. I know Dyson highly recommends RLI, but I don't think it's appropriate for every application (I.e., 571 miles/month applications.) I'd love to see how something, like the aforementioned MC, compares.
Meh meh meh. Let me see how the next run does before jumping to conclusions. If anything I would run PP in it like I do all the other vehicles.
Originally Posted By: Old Mustang Guy
The flashpoint seems low, even considering the fuel dilution.
The method used to test will result in a lower flash than blackstone. They are not directly comparable.
Last edited:
We really need to know where TBN started, to know if it dropped too dramatically, but on it's face, that's not very impressive.
The engine essentially never gets hot. The only reason it is 1.25% fuel dilute is because I make a point of getting it hot about once a week. If I drove it like my mom I wouldnt be surprised to see 5% dilute like her duratec. VOA TBN is 6-7, IIRC?
Last edited:
Not open for further replies.