Castrol 10W-40, '94 Celica, 7A-FE, 1.8

[robert]

Engine mileage, 39,000 (rebuilt), Miles on oil 1320. Car is used exclusively in city, stop and go, hot weather. Blackstone Labs (AC Delco filter Castrol 10W-40 GTX (dino)

AL 4

Chrom 0

Iron 2

Copper 3

Lead 1

Tin 0

Moly 101

Boron 299

Silicon 8

Sodium 3

Calcium 2056

Magnesium 10

Phos 845

Zinc 974

Barium 0

Antifreeze 0

Water 0

Magnanese, nickel, silver, titanium, potassium all 0

Visc: 65.4@210

Flashpoint 410

Fuel .5

Blackstone stated oil is doing well but did note the viscosity is barely 40. (Their acceptable range for 10W-40 is 65-76. They noted no signs of abnormal wear and stated average sample for this type engine and oil is 4788 miles. Recommended I use that interval for next sample.

I sampled at only 1320 miles to check for wear and condition of engine. I did not ask for TBN because my normal change interval is 2000 miles because this little car is driven under severe, very severe conditions, worry about sludge, and Toyotas are tight, hot running engines.

Any comments welcomed. How is ash determined? Also, can oxidation be determined from these figures. Thanks!

[ August 02, 2002, 06:12 PM: Message edited by: robert ]

 

[Patman]

The viscosity is actually 11.79cst at 100c, so it's not even 40wt at all anymore, it's 30wt (9.3 to 12.5 is 30wt)

I keep wondering, where does all this moly come from in Castrol GTX? Virgin samples on Maxima.org's spreadsheet show zero moly, yet all the GTX test results on used oil always show moly. Is this oil creating it's own moly?

Or is all this moly coming from the rings on these cars? (is it even possible for this much moly to come from ring wear?)

 

[Patman]

By the way, I don't believe oxidation can be figured out based on these numbers, a seperate test is required. Why Blackstone doesn't do it really boggles me. I don't know how they can help people determine proper intervals on their oil when they leave out such vital info. And the fact that they charge more for TBN just ensures that most people don't get it, which is also vital for determining proper intervals on an oil.

 

[robert]

Patman - Thanks for comments.

 

[Terry]

Robert the engine looks very solid for a rebuild.
The moly is from the oil, seems that this brand like others can't seem to decide exactly what ads they want to use on any given day of production runs.
You cannot tell much about Oxidation from your test results.

Patman is right ( all that training is paying of Dude ) the oil above is solidly a 30w. Try another brand and see if your engine shears it like the castrol. And check to see if wear Values are stay low.