Oil
Le Mans Master
Joined: Jul 2005
Posts: 5,328
Likes: 405
0W30, oil is like a religion so you'll have all kinds of opinions as to which brand is the best. Having said that, I use Mobil 1 but any of them will work just fine, even the Walmart/auto parts store brand. GM specified 5W30 for your car when it was new and even with 109K miles on it, there is no need to go to an xW40 oil. My daily driver has almost 200K miles on it and I use 5W30 with fantastic oil pressure hot and cold.
Team Owner
Joined: Aug 2005
Posts: 34,988
Likes: 515
From: Riverside County Southern California
Co-winner 2020 C4 of the Year - Modified
2018 Corvette of Year Finalist
2017 C4 of Year
2016 C7 of Year Finalist
St. Jude Donor '09 thru '20
I always use 10W30 Mobil 1 on both Vettes and my DD.
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Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
C4's use a 5W-30 oil as the recommended grade. Even with over 100K miles on the car, stay with the 5W30.
The owner's manual shows a temperature range for the 5W-30 is from -20 F to over 100 F. 10W-30 should not be used at temps below 0 F.
The owner's manual shows a temperature range for the 5W-30 is from -20 F to over 100 F. 10W-30 should not be used at temps below 0 F.
Burning Brakes
Joined: May 2009
Posts: 1,027
Likes: 1
From: Woodland CA
Most vehicle manufacturers today specify 5W-20 or 5W-30 for newer vehicles for year-round driving. Some European car makes also specify 0W-20, 0W-30, 0W-40 or 5W-40 for their vehicles. Always refer to the vehicle owners manual for specific oil viscosity recommendations, or markings on the oil filler cap or dipstick.
As a rule, overhead cam (OHC) engines typically require thinner oils such as 5W-30 or 5W-20 to speed lubrication of the overhead cam(s) and valve-train when the engine is first started. Pushrod engines, by comparison, typically specify 5W-30, 10W-30 or 10W-40.
As mileage adds up and internal engine wear increases bearing clearances, it may be wise to switch to a slightly higher viscosity rating to prolong engine life, reduce noise and oil consumption. For example, if an engine originally factory-filled with 5W-30 now has 90,000 miles on it, switching to a 10W-30 oil may provide better lubrication and protection. The thicker oil will maintain the strength of the oil film in the bearings better so the engine will have more oil pressure. This will also reduce engine noise and reduced bearing fatigue (which can lead to bearing failure in high mileage engines).
As a rule, overhead cam (OHC) engines typically require thinner oils such as 5W-30 or 5W-20 to speed lubrication of the overhead cam(s) and valve-train when the engine is first started. Pushrod engines, by comparison, typically specify 5W-30, 10W-30 or 10W-40.
As mileage adds up and internal engine wear increases bearing clearances, it may be wise to switch to a slightly higher viscosity rating to prolong engine life, reduce noise and oil consumption. For example, if an engine originally factory-filled with 5W-30 now has 90,000 miles on it, switching to a 10W-30 oil may provide better lubrication and protection. The thicker oil will maintain the strength of the oil film in the bearings better so the engine will have more oil pressure. This will also reduce engine noise and reduced bearing fatigue (which can lead to bearing failure in high mileage engines).
