Oil pressure on 2010 Grand Sport

**eastNC07vetteman** · 05-12-10, 09:44 AM

I purchased a 2010 Grand Sport recently, it has 155 miles on it. I have noticed that while driving the oil pressure goes from 52 psi to 72 psi, and has topped at at 80 accelerating when cold, is this normal?

**NORTY** · 05-12-10, 01:05 PM

The oil pressure is EXTREMELY dependant upon the oil temperature and RPM. You must include the oil temperature & RPM for a comparison. I drove a new GS a couple weeks ago (it had <20 miles on it.)
I noticed the oil pressure varied from 22 PSI to 75 PSI. With this info only, it's useless. You gotta have temp & RPM info also!

**rkoblin** · 05-19-10, 07:20 PM

mINE HAS 2100 MILES ON IT AND YEAS, WHEN IT IS COLD THE PSI IS TOPPED OUT. ATER A FEW MINUTES IT GOES BACK TO A NORMAL RANGE.

jUST DO NOT JUMP ON IT FOR THE FIRST COUPLE OF MILES.

**Hib Halverson** · 05-19-10, 07:27 PM

It is normal.

For best durability, I'd change the oil and filter at 1000 miles and swtich to a synthetic 10W30. Mobil 1 is good, Red Line is best. After that, use the oil life moniter but change a filter at 50%.

Some engines need 3000-5000 miles before they fully break-in.

**AlHewitt** · 05-20-10, 11:29 AM

Hi Hib,
Help me understand why Red Line @10W30 is better than what GM recommends, notably Mobile 1 5W30. I'm well aware of the function of oil in piston powered aircraft engines and I believe that high performance automobile oils to be similar. Are there additives in the Red Line oil that promote better protection from corrosion than those found in Mobile 1? I assume that both are synthetic, something that I personally am not a fan of (in airplanes). But reading about the requirements for 'roller motors' I guess I see the need for the synthetics. I think my question is; which oil can I use that will allow the engine to go the distance? If after 10 years of intermittent use at best - my GS is not a daily driver - which oil should I use that will have the engine running without issues – 10 years from now?
Thanks for your comments – always appreciated… Al

**Hib Halverson** · 05-20-10, 01:18 PM

First of all it's "Mobil" not "Mobile". As much as Mobil 1 is not my choice in engine oils, with due respect to the brand which revolutionized the consumer synthetic engine oil market, we ought to use the right name.

Both Mobil 1 and Red Line are synthetics but their base stocks vary quite a bit.

M1 has a synthesized hydrocarbon base...as are many mass-marketed synthetic oils.
Red Line, along some other premium synthetics, such as Amsoil and Neo, has an ester base. If you know aircraft lubricants, then you know that all turbine engine oil is ester based and you understand the advantages they bring to the table as far as stability in high temperature environments.

Also, on that note, why are you not a "fan" of synthetics in recips?

As for the viscosity issue, GM wants you to use 5W30 as a fuel economy enhancement. For best long-term durability I recommend a 10W30. It works better at high oil temps and lubricates better because it has less VI improvers which are still used in synth. hydrocarbon based products.

The requirement for synthetic oil in modern Corvette engines is not driven by their being "roller motors". It's driven mainly by oil temperature. What is sensitive to the type of lifters (ie: roller or flat tappets) is the engine oil's additive package, but...I digress. The engine oil and flat tappet camshaft issue is really off-topic.

**AlHewitt** · 05-20-10, 10:27 PM

Feel better now Hib? Thanks for the clarification or should I say the English lesson, I thought I was back in grade school there; Spell Check must have let me down, again…

With respect to synthetic oils, there are many reports as to piston powered aircraft engines that typically run at 75% + power continuously having sludge build-up when using synthetic oils. It was about ten years ago I believe that Phillips pulled their multi weight synthetic aircraft oil off of the market after a number of engine failures were attributed or associated with this oil. I know of no one using synthetic oil in a piston powered airplane today… I have run straight 50 weight Shell detergent oil for the last 25 years in my ‘big bore’ Continentals and always try and preheat the engine when the WX is cold – less than 30 degrees F. Some like the multi vis. stuff but I have avoided it opting for straight weight oil that resist thinning with high operating temps and I change it regularly. My oil pressure stays at 60+ psi during a climb in the hot summer months where the oil temps can reach upwards of 240 F. BTW, 40 years ago I flew airplanes with big round piston engines at 3000+ HP for Uncle Sam. 50W detergent oil was all that was used.

Most automobile engines run at a much lower power setting so I believe using multi weight and synthetic oil is all about better lubrication during cold starts and better lubrication of the very small bearings found in roller motor’s valve trains. The valve train pressures are said to be the highest found in these engines and when roller lifters and rockers started to appear Chev began requiring synthetic oils. It has been my experience that rarely do auto engine oils get much above 200 degrees F in normal use. Here in the NW where the average temps vary between 40 and 70 degree F. 20W detergent oil changed regularly would probably work fine in these machines. I'll be using the Mobil (that's with out the e Hib) 1 - 5w30 in the future... Cheers Al

**Hib Halverson** · 05-20-10, 11:20 PM

Originally Posted by AlHewitt

(snip)

I have run straight 50 weight Shell detergent oil for the last 25 years in my ‘big bore’ Continentals and always try and preheat the engine when the WX is cold

AeroShell 100W is what my Dad used in the Lycomings in the Aero Commander 680B we used to own, but that was ages ago. I can remember having to help him set-up space heaters under the engines before trying to start them on a trip to northeastern Montana we took one Christmas.

My Brother-in-law owns an aircraft service business in Nevada. I gotta ask him about synthetics in piston engines.

0– less than 30 degrees F. Some like the multi vis. stuff but I have avoided it opting for straight weight oil that resist thinning with high operating temps and I change it regularly. My oil pressure stays at 60+ psi during a climb in the hot summer months where the oil temps can reach upwards of 240 F.

Betcha you're at 275°F in bearings. That's right at the limit of a petro-based oil's temp range.

What do you fly, now?

BTW, 40 years ago I flew airplanes with big round piston engines at 3000+ HP for Uncle Sam. 50W detergent oil was all that was used.

A-1?

Most automobile engines run at a much lower power setting so I believe using multi weight and synthetic oil is all about better lubrication during cold starts and better lubrication of the very small bearings found in roller motor’s valve trains. The valve train pressures are said to be the highest found in these engines and when roller lifters and rockers started to appear Chev began requiring synthetic oils.

Chevrolet introduced roller lifters on Corvette in 1986. Mobil 1 wasn't introduced until 1992. Roller rockers were not used until 1996 on a very few engines and 1997 across-the-board. Today, all Corvette engines have both.

There reason GM went to Mobil 1 in 1992 was the LT1's 300-hp SAE net and higher oil temperature, not roller lifters.

It has been my experience that rarely do auto engine oils get much above 200 degrees F in normal use. Here in the NW where the average temps vary between 40 and 70 degree F. 20W detergent oil changed regularly would probably work fine in these machines.

You might want to research that 200° rule-of-thumb a bit. With modern engines, I'd say one that runs sustained 200° oil temp would be an exception rather than a rule. Now, if the engine has an non-thermostatically-controlled oil cooler, I'd agree. Of the five vehicles I have in my project car fleet, the only two that run sustained oil temps during normal driving of about 200 are the two with coolers, my 71 BB Coupe and the 95. Everything else runs hotter. For instance, my 01 Camaro, is for the most part my daily driver. Once the oil temp stabilizes it sits 220-240.

**motorman** · 05-21-10, 01:52 PM

does red line oil meet the GM spec GM4718M for the oil because if not GM can void your warranty. here is the list.http://www.gm.com/corporate/responsi...ngine_oils.pdf

**motorman** · 05-21-10, 02:10 PM

Originally Posted by eastNC07vetteman

I purchased a 2010 Grand Sport recently, it has 155 miles on it. I have noticed that while driving the oil pressure goes from 52 psi to 72 psi, and has topped at at 80 accelerating when cold, is this normal?

the 6 speed manual GS have the ZO-6 type dry sump system and the pressure will be different than the wet sump GS

**motorman** · 05-21-10, 03:08 PM

Originally Posted by Hib Halverson

AeroShell 100W is what my Dad used in the Lycomings in the Aero Commander 680B we used to own, but that was ages ago. I can remember having to help him set-up space heaters under the engines before trying to start them on a trip to northeastern Montana we took one Christmas.

My Brother-in-law owns an aircraft service business in Nevada. I gotta ask him about synthetics in piston engines.

Betcha you're at 275°F in bearings. That's right at the limit of a petro-based oil's temp range.

What do you fly, now?

A-1?

Chevrolet introduced roller lifters on Corvette in 1986. Mobil 1 wasn't introduced until 1992. Roller rockers were not used until 1996 on a very few engines and 1997 across-the-board. Today, all Corvette engines have both.

There reason GM went to Mobil 1 in 1992 was the LT1's 300-hp SAE net and higher oil temperature, not roller lifters.

You might want to research that 200° rule-of-thumb a bit. With modern engines, I'd say one that runs sustained 200° oil temp would be an exception rather than a rule. Now, if the engine has an non-thermostatically-controlled oil cooler, I'd agree. Of the five vehicles I have in my project car fleet, the only two that run sustained oil temps during normal driving of about 200 are the two with coolers, my 71 BB Coupe and the 95. Everything else runs hotter. For instance, my 01 Camaro, is for the most part my daily driver. Once the oil temp stabilizes it sits 220-240.

air craft oil must be ashless. back in the day we used av oil in the race cars to prevent piston burning

**motorman** · 05-21-10, 03:12 PM

• GM4718M

Your vehicle's engine requires a special oil meeting GM Standard GM4718M. Oils meeting this standard may be identified as synthetic. However, not all synthetic oils will meet this GM standard. Use only an oil that meets GM Standard GM4718M.

Notice: Using oils that do not have the GM4718M Standard designation, can cause engine damage not covered by the vehicle warranty.

• SAE 5W-30

SAE 5W-30 is best for the vehicle. These numbers on an oil container show its viscosity, or thickness. Do not use other viscosity oils such as SAE 20W-50.

**Hib Halverson** · 05-21-10, 04:31 PM

Thank God we have "motorman" here to read the owner's manual for us.

Red Line Engine Oil have never been certified under 4781M. They exceed that standard. Red Line, and a few other premium synthetic makers choose not to certify because 1) the cost of the certification and 2) it locks them into oil formulae which cannot be changed as lubricant and additive technology changes.

**corvettez06** · 08-23-10, 09:50 AM

Mobil 1 is great oil. I have used it for years in everything and no problems what so ever. Plus, its available under a GM part number so its most likely available at almost any GM dealer, if you ever have to add any.

**tommy9052** · 09-06-10, 09:23 PM

Ive had mine a week now and oil pressure is between 40 and 80 just cruising at 65mph its 60psi. called the dealer on my way home from the dealer last week and they said that was normal. Mine has the dry sump system (coupe 6speed manual )