<center><img src="http://im1per.shutterfly.com/procserv?si=00002937301920020330013138700.JPG&ps=0 &rx=640&ry=480"></center><p>
Ran some TGA scans on Mobil 1 motor oil. Surprise, surprise. Tri-synthetic formulation has 3 loss peaks, imagine that. Oil contains polyalphaolefins, esters and alkylated aromatics. As expected volatility ran 0W, 5W, 10W and finally 15W. The higher residual of the 15W-50 is due in part to the greater amount of anti-seize compound in the oil.

My big surprise was when I looked at my car's back seat. Someone had overstacked the oil cases and cracked the oil containers at the base of the bottle's neck. Nice puddle of oil nestled in the seat. Possible leather conditioner, but I have cloth seats.

Test method: One drop of oil (18 mg) was placed in a 10 mm diameter platinum pan. The oil was heated in a nitrogen atmosphere, 60 ml/min purge. The heating rate was dynamic, fastest was 50°C/min where there was no weight loss slowing to a minimum of 4°C/min where the weight loss was at a maximum.

 

application?

 

a APR stage 2 on the graphs? What info do I need to give you to do this? Kinda like when you did the GIAC & Borla Combo

 

What he said ^^^^^^^

 

Low volatility is desirable for a number of reasons. Lower volatility results in lower oil consumption that gives rise to a more stable oil viscosity. When light fractions boil off the heavier residual has greater viscosity. This causes a reduction in both power and fuel economy with running time. Some fuel saving oils (low viscosity) had higher volatility that resulted in diminished fuel savings with time. Newer certification tests require measurement of fuel savings both after the break-in period and at the end of the test run. I'm hoping Mobil will bring data to Asheville showing fuel economy vs. run time for the various grades of Mobil 1. From the graph above 10W-30 should have a more uniform response than 0W-40. Lower volatility is also safer in areas of high dynamic pressure gradients. Low pressure areas promote the formation of small gas bubbles than upon collapsing will induce high stresses in nearby metal surfaces. The stress can be high enough to pit the surface of bearings or journals. Low volatility may indicate the possibility of high film strength. As the separation distance decreases the viscosity increases due to orientation of the molecules. This increases the load bearing capacity and reduces the possibility of metal-to-metal contact. A low volatility / high film strength oil is ideal for cylinder lubrication purposes. Reducing oil consumption reduces fouling of emissions equipment with anti-wear / anti-seize compound additives. Higher levels of additives improve wear reduction on camshafts and similar high pressure service but at the detriment to deposit contamination. The higher levels in 15W-50 may be offset by its lower volatility. Mobil could present us with data at Asheville, to show if this is indeed true. The volatility reduction also reduces the detrimental build-up of material on turbocharger turbine vanes. Mercedes Benz has an oil performance test for one of their Diesel engines (11L V6) that looks at the reduction in attainable boost from oil combustion deposits. Maybe Mobil will present data on Mobil 1 oils subjected to this test.

 

If so log blocks 2, 3, 20, 34, 43, 120, 204 for starters. If it's a 2002 toss in 91 also. Run tests in 4th gear from idle speed to rev limit. Be careful and don't get a ticket. Before you start the engine log blocks 4 & 112 for a few seconds.

 

thanks

 

then the 5, 10 or 15W oils. John a more down to earth explanation would be big help.

Thanks

 

<center><img src="http://im1per.shutterfly.com/procserv?si=00002937301920020330044023860.JPG&ps=0 &rx=640&ry=480"></center><p>
Solvent refined paraffinic base (Group I), hydrotreated base (Group 2), hydrocracked bottoms stream (Group III), polyalphaolefins (Group IV), other (Group V). Group II is probably the cheapest to make but requires a greater capital outlay for equipment compared to Group I. Only recently, with the more stringent requirements of engine manufactures, has Group II commandeered a higher price point. Neither of these oils can compete on performance grounds with a Group IV oil, such as Mobil 1. Given the cost difference they don't have to (more on how that's changing later). Group I oils of 0W or 5W are unlikely to meet the requirements of the tightened Noack volatility limit and they are also hard pressed to meet the other requirements of API (American Petroleum Institute) SL or ILSAC (International Lubricants Standardization & Approval Committee) GF-3 ratings in a cost effective manner. That's one of the reasons its taken so long for the new standards to become adopted.

<A HREF="http://search.chemweek.com/~lw/start_search/0800/dept.auto%2018.html"> Click here for a snippet of how things progressed.
</A>

In the end Sequence IIIF was adopted and a compromise between the oil producers and engine makers was made to get approval of TEOST MHT-4. Engine makers wanted a max limit of 30 mg on piston deposits, oil producers were happy with the 60 mg limit of TEOST 33C. Adopted was TEOST MHT-4 with a limit of 45 mg. Ford stuck to their guns and limit 30 mg performance on oil for their new cars and also require passing a double length Sequence IIIF test. They're serious about pushing the longer oil change intervals. It's understandable, I hear Audi wants to charge $80 for an unscheduled oil change on the TT. Cost of this level makes higher performing (more costly) oil economically advantageous.

The chart here shows weight loss vs. temperature (same test as the weight loss rate chart posted earlier). The test has a high surface to volume ratio and continuous nitrogen purge so results are a measure of the oil characteristics and not a measure of how limited the evaporative interface is. The Noack test is a test (ASTM 5800) that holds the oil at 250°C for 1 hour. The test method does constrain the oil's natural ability to evaporate. Mobil 0W-40 oil (the most volatile in my test) reports 10% for Noack test and claims ACEA A3 certification (Noack limit of 13%). The closest I got to this or the 15% limit of SL or GF-3 is with the 15W-50 oil. In my test the time from room temperature to 250°C was only 11 minutes.