I just changed to Amsoil after using Mobil 1 for the first 15k miles. Before I made the change though, I sent in the used Mobil 1 for analysis. I will probably do the same with the Amsoil around the 22,500 mark, once I know all the old Mobil 1 is flushed out (I do changes every 3,750).

From what little I know of the topic though, it looks like the Mobil 1 held up pretty well. Driving was mixed highway/city...

JW

 

nice

 

How much it cost for the oil analysis ?

 

Yeah, how much did it cost? Sounds like your oil had plenty of life left, and you could move to a 5000 mile change schedual. If analysis isn't too expensive, I will do samples every 2,500 miles after my next change to determine when it actually NEEDS changing. If you can extend your change interval without causing any harm (as proven by analysis) you can save a hell of a lot of money..... unless the analysis cost $100 or something like that

Keith

 

OK guys, just did some research by googleing "Blackstone Laboratories".

Analysis cost $20 with an extra $10 for "TBN" analysis. TBN measures the amount of active aditives left in the oil and is needed for determining if you can go up to an extended change interval. Oh, and they send you a free oil sample collection kit.

In my view, if you want to go to an extended change interval this is well worth the money! I am going to do this on my current oil at aprox 5,000 miles and see how things turn out

Keith

 

good info!

 

I'm not looking to do extended oil change intervals; I just wanted to see how the motor was holding up and to see how Mobil 1 compares to Amsoil and whatever else I might try down the road. At $30 a pop (including TBN), I don't see these analyses as being terribly cost effective to do frequently, even if I were doing extended intervals. Now if I had a 911 Turbo with a 12 qt (give or take) oil capacity, it might be a different story...

JW

 

I just want to get a base line over a span of around 7,500 miles with samples at 2,500 miles, 5,000 miles, and 7,500 miles. If the oil looks good for that entire span I will just stick with a 7,500 mile interval and do samples every 15,000 after that. If it is looking "iffy" at 5,000 I will go ahead and change it and stick with a 5,000 mile interval. I highly doubt that we need to do oil changes every 3,000 miles. As your analysis showed, you had lots of life left in your oil at almost 4,000 miles.

Later,

Keith

 

But what about all the dirt & contaminents that build up in the oil? I thought the main reason for changing it was to flush all that out of there instead of circulating it through the engine?

 

That is what the filter is for. The oil analysis checks for solids in your oil as well as checking the chemistry of it, and if there is a bunch of crud in it, it will be changed ASAP.

Keith

 

Yup. The filter provides the ability to reduce the "insolubles" found in the oil. This is stuff like suspended carbon, large metal particles that aren't observed in the FTIR section (the 'main' numbers) and also oxidized particulates.

However, don't try filtering too aggressively or the oil flow will be too low to provide adequate lubrication. I can spout numbers about a car run without an oil filter (just a cap) that had slightly better wear numbres than with running a filter.

Yet as cars are 'built' to provide longer drain intervals, the ability of the filter to provide high-quality filtration is a necessity. Balancing that with flow is where the engineering of filters comes into play.

ferb!

 

My oil change has been performed, and the oil sample is on it's way to Blackstone labs right now. I should have my results by e-mail as soon as the anaylysis is completed.

Keith

 

I wish we could delet our own posts.

Keith

 

As promised, here is my analysis for comparison. I have 13,000 miles on my car, and new HKS cams were put in just after my last oil change 5,000 miles ago. The report says the small amount of fuel may be due to extended idleing or racing, I think it is probably due to idleing pig rich with the HKS 272's

Keith

 

They seem like a pretty friendly company too, I like that the comments are in a conversational mood.