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Oil Type
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Joined: May 2004
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From: Los Angeles CA
Oil Type
Had my oil changed today by my trusted mechanic. Manual states Mobil 1 5W30, ok for 10W40, but never 20W50. I live in So. Cal, so temp is not as critical as other areas. My guy put in Mobil 1, but 15W50. he says it is better for our region. Should I be concerned? I seem to be running higher oil pressure, around 50-60 lbs., when stayed around 40 lbs. before. Should I drain it out?
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From: Manassas Park VA
St. Jude Donor '07-'08,-'13-'14, '16-'17
Originally Posted by Tom73
I would not use anything more than 10W30. I would have your mech replace it with the correct 5W30.
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Willfulone
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From: Mustang OK
Originally Posted by Tom73
I would not use anything more than 10W30. I would have your mech replace it with the correct 5W30.
tom...
tom...
My '03 GM Service Manual states, "SAE 5W-30 is the only viscosity grade recommended for your vehicle." It does go on to say, "If the temperature range is 0*F (-18*C) or above SAE 10W-30 oil which has the API Starburst symbol is acceptable if SAE 5W-30 oils is not available. Areas where the temperature falls below -20*F (-29*C), it is recommended either an SAE 5W-30 synthetic oil or an SAE 0W-30 oil. Both will provide easier cold starting and better protection for the engine at extremely low temperatures." It specifically states, "Do not use other viscosity oils, such as SAE 10W-40 or SAE 20W-50 under any conditions." I think you will find that your owner's manual reads much the same.
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I would have the mechanic change it back to what is recommended by GM. There is nothing wrong with running 5W-30 oil in the car, especially in your area.
Burning Brakes
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From: St. Robert Missouri
Originally Posted by Trocness
Thanks. I went back and had him drain out the 15W50 and put in the correct 5W30 (which I bought myself!). I feel much better now.
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From: Hells Sister City Phoenix AZ
St. Jude Donor '03
I use 10/30 but our summers are definitely more severe than yours in CA. 15/50 is overkill IMHO. Problem solved but he should have paid for the change if he was the one that f'd it up to begin with.
Drifting
Joined: May 2000
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From: Southern NH
Originally Posted by Tom/99
I don't use anything but 10W-30 oil, in all my cars. Since I have lived in Texas, the temperture has been as low a 9 degrees and as high as 110.
When I got the car and lived in Florida, only used 10/30. Even now in New England, the car is rarely used in the winter, and if I take it out the temps are above freezing, so I've stuck to 10/30.
With Mobil-1, the difference between 5/30 and 10/30 is almost neglible.
