I'm glad somebody brought this up; I've been thinking about this for several days since getting back my last sample. I think it is important to take Blackstone's comments with a huge grain of salt. Blackstone is trying to do a good job, so they always say something just to give us food for thought. But their comments are either provided by an artificial intelligence computer program, or written by someone who is in a hurry and has to comment on dozens of samples per hour. Here's my evidence:
When I turned in a sample and told them I was especially interested in silicon (because of my K&N filter), the Blackstone comments that came back included: "Nice improvement in wear and silicon. " My Si was 7 after 7685 miles on this sample, compared to a "universal average" of 9, which is based on 5000 miles, so anything below 13. 5 would have been "better than average" for my number of miles driven, and the Blackstone comments were accurate. I then continued using the same oil for another 8121 miles, and silicon went to 8 on the next sample. But this time I didn't give Blackstone any hints about what I was looking for. Their comments came back "Silicon shows air filtration could be improved. " This comment doesn't make any sense at all. If "7" was a "nice improvement" at 7685 miles, then rising only 1 ppm to a total of "8" at 15,806 miles on the same oil should set off church bells in Philadelphia! Based on their averages, my silicon is at less than 1/3 of "average" values, so it's going to be hard to improve further. I do not mean to sound highly critical of Blackstone - I think they are doing good work. But I also believe that you can learn more by looking at several reports and thinking about YOUR truck and YOUR samples for an hour, than what a technician somewhere can tell you based on glancing at the same data for 15 seconds. I have NO DOUBT that if anything serious was happening like a coolant leak, then that is where the Blackstone technician's experience would kick in and they would quickly alert us to the problem. But I also believe that the desire to put some comment on EVERY sample (even "boring" samples where nothing interesting is happening) leads to casual comments that are sometimes a little off base.
P. S. - On wear rates, at 40k, mine are still going down with each sample, even using the same brand oil. If you read all the oil sample posts and jot down the numbers, you'll find the guys with more miles almost always have lower wear rates. While synthetic might get slightly lower wear rates, my reasons for using it are better cold starts, reduced turbo coking / hot shutdowns, and more time between changes, which makes it possible for me to find time to do the changes myself and keep others away from my baby. But I have no doubt that Delo and some of the other non-syns are great products too.
------------------
2001 ETH, QC, LWB, 4WD, 3. 54, SPA Pyro & Boost, K&N RE-880 w/foam pre-cleaner, ARE Z-series Cab-high shell, Rear ARB locker, and all kinds of synthetic fluids...
[This message has been edited by HC (edited 06-01-2001). ]
Attention: TDR Forum Junkies 
