Castrol GTX 10w-30, 3442 miles,GM 5.7l V-8 (L31)

[doctormdds]

Castrol GTX 10W-30
1996 Chevrolet full size pickup
350 cubic inch engine (L31)
93,463 miles on vehicle
3,442 miles on oil
Oil in service Dec. 7, 2003 to May 6, 2004 (6 months)
AC Oil Filter, Fram(!) Air Filter
Makeup oil: none

Here are the results: Mine/Universal Averages

Aluminum - 4/8
Chromium - 0/2
Iron - 11/41
Copper - 4/16
Lead - 12/23
Tin - 0/3
Molybdenum - 53/35
Nickel - 0/1
Manganese - 0/1
Silver - 0/0
Titanium - 0/0
Potassium - 9/9
Boron - 1/42
Silicon - 15/23
Sodium - 2/18
Calcium - 2000/1767
Magnesium - 4/448
Phosphorus - 785/822
Zinc - 1080/997
Barium - 0/1

Sus Vis@210 - 60.4/60-69
Flashpoint - 390/>375
Fuel% - Antifreeze% - 0/0
Water% - 0/ Insolubles% - .4/

Blackstone's Comments:
We can tell you've been taking good care of this engine! Universal averages show typical wear
from this type of engine after 3800 miles on the oil. Your oil was in use 3442 miles, and wear read well
below those averages, showing a nicely maintained engine with no mechanical issues that we can see.
Insolubles were low at 0.4%, so your oil filtration schedule is working well. Silicon was fine at 15 ppm,
showing no problems at the air filtration/induction system. You'll see 100,000 miles no problem -- and you
just might get to 300,000, as well as the engine is wearing!

My Comments:

I have owned this truck since new and only used Castrol GTX 10W-30 oil, AC oil filters and regular oil changes typically at 3,000 miles. This is my first oil analysis on this vehicle. As you can see, I don't put a lot of miles on the vehicle. It took me 6 months to put 3442 miles on it - less than 600 miles a month! I mostly drive it to work and back which is about 3 miles away. I had the infamous GM intake manifold leak repaired at 55,000 miles so I was kind of worried that this UOA might show coolant in the oil. I must say, I'm pleasantly surprised and a little shocked to see a GM V-8 show such good wear numbers. I do not baby this truck nor do I abuse it. The only thing I do out of the ordinary is I NEVER start the engine and immediately drive away. I typically allow about 30 seconds for the oil to circulate before putting the truck in gear - longer in cold weather. Could this be the reason for such good wear numbers? Who knows. This certainly seems like an anomoly to me - a GM V-8 with Toyota like UOA numbers. At this oil change, I added a bottle of Auto-Rx. Once I complete the treatment I may do another analysis a couple of oil changes down the road so that we can all compare. Incidentally, while I added no make up oil, my oil level was nearly 1qt low at the time of the oil change. I do have an oil leak but I'm unsure where from. Hopefully, the Auto-Rx will help. I appreciate comments from everyone. I love this site!

 

[like a rock]

Nice report. Good to see Castrol Gtx do a nice job and hold it's viscosity. I would bet if you tore down this engine would be clean inside. I also am using Castrol products and think they do a great job.

 

[mikep]

Nice report. Sure does look as though that engine like what you've been feeding it. I too always felt GTX was an excellent motor oil.

 

[JohnBrowning]

Nice report. The Gen II small block in your truck is a gem. They pretty much had all the bugs worked out of this design other then gasket leaks. Is your Central Port Injection? If so they had some issues with carbon onthe popet valves and some EGR carbon issues. Regular cleaing of the injectors at 30,000 to 50,000 mile intervals will keep you from haveing to do the "Three Piece Meal" Upper intake manifold gasket, CPI, Nut Kit. If your is not CPI do not worry about it.

In the Republic of California GM has to warranty the CPI systems for 300,000 miles. C.A.R.B. sued GM because the system was so fualty and GM settled with them by agreeing to service any 4.3,5.0 and 5.7's that had the CPI system for 300,000 mile.

 

[Santo Fontana]

quote:

---

Originally posted by JohnBrowning:
Nice report. The Gen II small block in your truck is a gem. They pretty much had all the bugs worked out of this design other then gasket leaks. Is your Central Port Injection? If so they had some issues with carbon onthe popet valves and some EGR carbon issues. Regular cleaing of the injectors at 30,000 to 50,000 mile intervals will keep you from haveing to do the "Three Piece Meal" Upper intake manifold gasket, CPI, Nut Kit. If your is not CPI do not worry about it.

In the Republic of California GM has to warranty the CPI systems for 300,000 miles. C.A.R.B. sued GM because the system was so fualty and GM settled with them by agreeing to service any 4.3,5.0 and 5.7's that had the CPI system for 300,000 mile.

---

I serviced those once on a 4.3l. Very strange way to distribute the fuel. Dont forget all the o rings

 

[Patman]

Have you considered trying GTX 10w40 for the warmer months? It would be interesting to compare. I bet lead would come down a lot.

 

[doctormdds]

JohnBrowning, I have no idea if I have Central Port Injection but I think I do. My engine is the first year of the Vortec 350. Regarding the carbon issue, my friend, Robert, is a tech at a GM dealership. Robert does work on my truck at his home. He has "decarboned" the engine as a preventive measure on at least one occasion as he is aware carbon buildup has been a problem. I have had no fuel injector issues but I've heard of others that have. Admittedly, I'm a novice interpreting UOA results, but this report looks so good to me that I hate to change something that's working so well. I plan on continuing my OCI and oil type. Thank you all for your comments.