A question for oil experts

R W

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Nov 23, 2005
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Location
Amble,Northumberland
Your Mercedes
2001 E320cdi/ Sclass 2012 350cdi
I am working in Kyrgyzstan where scams, rip offs & corruption is a normal/accepted way of life here. I took my E290td to a service station last week for an oil change. I wanted 5w/40w fully synthetic as used previously. Last time they used sealed containers of the oil but this time they topped it up from a bulk barrel? After leaving the service station I was studying the service info & they had recommended next oil change at 8k kms.(5000mls) . That indicated to me, I thought, mineral oil engine oil changes. I suspect he has charged me for fully synthetic & used mineral oil, after all who would check normally, & it would be a very easy scam for him to get away with.

I decided to try a little experiment as we run generators using 15/40 mineral. I took a polished SS plate & froze it at -17degC in the freezer. I took a drop out of my engine placed it on the plate, then took a drop (same size drop) of new 15/40. Both oils created the same size pool on the plate horizontally. I then put the plate in the freezer vertically for 24hrs.After 24hrs I would have expected the 5w 40w to have “run” further down the plate, but as I suspected it didn’t, they both measured exactly the same.

I realise my test is a little crude & I may be completely wrong but I would like to find out what oil I have before confronting the station. I am returning to UK next week, is there anywhere to have a sample of my oil analysed to check what oil is in my engine. I am located in North East UK so if anyone could recommend anywhere to have the oil analysed I would be grateful.
 
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Frontstep

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Your Mercedes
T210 320cdi
I hope some one answers that one for you as I would like to know.
I would do a cold pour test as well, I do know synthetic molecules are supposed to be uniform so maybe a microscope ?
We shall see what happens.
 

television

Always remembered RIP
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Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
There must be some labs that can do this, but I just do not know, the mineral oil should break down molecule wise earlier than the fully synthetic, but so much more to it all, I know we take the figures on the cans for granted.

Maybe we do have an oil expert among us
 

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