: Cadillac Mobil 1 Oil

07-12-11, 07:52 PM
I'm reading a lot of conflicting information on this website.

I noticed that the 2008 Cadillac STS has the Mobil 1 oil on the filler cap. Is this oil a requirement or recommendation? How do one determine if the previous owner has been changing the oil using the Mobil 1 or not?

And what happens if one uses regular oil than the Mobil 1?

Any other inputs would be greatly appreciated.

07-12-11, 08:53 PM
Switching back and forth between standard and synthetic oil will do no harm. But synthetic is a much cleaner oil I have found mobil 1 to burn faster. I use castrol syntec it does not break down as fast. As for finding out what the prior owner ran in it no way to know for sure unless you have his service records.

07-12-11, 09:22 PM
I use Mobil 1 Syntetic oil on my Cadillac Deville dhs 2001 5w-30 nd it runs very Smoth

07-12-11, 09:50 PM
Ok. Thank you.

How can one tell which oil is in there? Can you really smell the difference as indicated in this forum?

Secondly, should you really go by the actual mileage or the oil life monitor is sufficient?

Lastly, does the OLM differentiate between the oil life between regular oil and synthetic?

07-12-11, 10:43 PM
I don't understand your confusion.

My owners manual specifies GM4718M Spec for the V8 or GM6094M for the V6. Use of anything else may void your warranty, but why would I use anything other than Mobil 1 in my Northstar V8?

When I didn't know what was in my crankcase, I changed it and reset the (Society of American Engineers Award-Winning) Oil Life Monitor. I change it when the monitor says to do so. More frequent oil changes won't hurt but probably only have any value under 10,000 miles.

07-14-11, 07:46 PM
Please USE the recommended Viscosity for your car. If you could drop the pan, and
see the small oil scuuper, and the area of the screening to screen large chunks,
you would ONLY use the recommended viscosity.
The lighter oil, serves to let if flow easier,reducing the amount of HP needed to turn
the oil pump, yielding more HP to the rear wheels.

07-15-11, 10:54 AM
As stated above the requirement is oils meeting a certain standard listed in the handbook.
Mobil 1 is the factory fill, and is a fine oil.
There is no way of knowing what the previous owner used.

Synthetic will generally give you superior life, wear, fuel efficiency, and usable power.

As stated elsewhere, the OLM is a good guideline, and is what is recommended in the manual.

chagrin falls
07-15-11, 10:03 PM
Believe it or not-a few months back I read in "Car and Driver" that Mobil pays GM something like .50 for having the Mobil 1 logo on thier oil filler caps. From what I understand GM is now only using general specs on the caps-not brand specific. Correct me if I am wrong.

07-15-11, 10:08 PM
I wouldn't be surprised if oil makers have to pay GM for testing their oil and the right to print the GM spec on their containers.

08-14-11, 10:55 AM
Mobile One is the best for the price .If you want better oil use Lucas oil but it is far expensive