Engine Oil.
Burning Brakes
Joined: Dec 1999
Posts: 1,088
Likes: 0
From: Silver Spring, Md.
I use a combination of Royal Purple 5w30 and Mobil 1 of same weight. Next change will be adding Mobil 1 Extended Mileage to the mix due to its high phosphorous content for the valve train longevity. The southern guys also use 10w40 M1 without worries. The RP meets GMs requirements as noted on their labeling.
Last edited by stinky; Jan 17, 2006 at 03:55 AM.
Melting Slicks
Joined: Feb 2005
Posts: 3,372
Likes: 0
From: Springfield VA,
There is a lot of debate about which is the best oil. The test that I have seen show Mobile 1 right up there with the best, Amsoil, Royal Purple. Since Mobile 1 is almost 1/2 of what Amsoil cost, most folks go with Mobile 1. I really doubt there is going to be much difference in our cars. Going with a high quality oil filter is just as important. Doesn't do much good to have a long lasting oil if you have a cheap oil filter that is not keeping the oil clean. I go with either K&N or Amsoil filters.
Racer
Joined: Nov 2004
Posts: 440
Likes: 0
From: North Potomac Maryland
Originally Posted by BlackC6
i searched and could not find a thread about this.
What do you guys use? The original Mobil 1, a different weight, or maybe a different brand? And why?
What do you guys use? The original Mobil 1, a different weight, or maybe a different brand? And why?
Melting Slicks
Joined: Nov 2004
Posts: 3,064
Likes: 6
From: Pinellas Park Florida
Originally Posted by stinky
I use a combination of Royal Purple 5w30 and Mobil 1 of same weight. Next change will be adding Mobil 1 Extended Mileage to the mix due to its high phosphorous content for the valve train longevity. The southern guys also use 10w40 M1 without worries. The RP meets GMs requirements as noted on their labeling.
To answer the actual question, I have been using mobil 1 5/30. However, since I put Royal Purple in to the trannie, I have been considering Royal Purple 5/30. I had used K&N filters, but I don't like the fact that it sticks down so far.
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Team Owner
Joined: May 2004
Posts: 82,175
Likes: 1,319
From: McKinney TX
St. Jude Donor '21-'22-'23-'24
I use what the owner's manual says to use on pages 5-16 and 5-17 of the 2005 owner's manual.
What Kind of Engine Oil to Use
Look for two things:
• 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.
You should look for and use only an oil that meets
GM Standard GM4718M.
Notice: If you use oils that do not have the
GM4718M Standard designation, you can cause
engine damage not covered by your warranty.
• SAE 5W-30
As shown in the viscosity chart, SAE 5W-30 is best
for your vehicle.
These numbers on an oil container show its
viscosity, or thickness. Do not use other viscosity
oils such as SAE 20W-50.
What Kind of Engine Oil to Use
Look for two things:
• 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.
You should look for and use only an oil that meets
GM Standard GM4718M.
Notice: If you use oils that do not have the
GM4718M Standard designation, you can cause
engine damage not covered by your warranty.
• SAE 5W-30
As shown in the viscosity chart, SAE 5W-30 is best
for your vehicle.
These numbers on an oil container show its
viscosity, or thickness. Do not use other viscosity
oils such as SAE 20W-50.
Race Director
Joined: Sep 1999
Posts: 12,434
Likes: 916
From: CONCORD NC
as long as it meets GM4718, you're fine. I often use Havoline Synthetic in my street car, as it is about $1 cheaper/qt than Mobil 1. Unless you are doing something extreme (extreme cold weather or high-temp track events), use 5w30.
Thread Starter
Burning Brakes
Joined: Nov 2001
Posts: 1,149
Likes: 42
From: Minnesota
Thread Starter
Burning Brakes
Joined: Nov 2001
Posts: 1,149
Likes: 42
From: Minnesota
Originally Posted by davidfarmer
as long as it meets GM4718, you're fine. I often use Havoline Synthetic in my street car, as it is about $1 cheaper/qt than Mobil 1. Unless you are doing something extreme (extreme cold weather or high-temp track events), use 5w30.
Should I use a different weight for a track day or an HPDE?
Thread Starter
Burning Brakes
Joined: Nov 2001
Posts: 1,149
Likes: 42
From: Minnesota
Originally Posted by Jagcvette
There is a lot of debate about which is the best oil. The test that I have seen show Mobile 1 right up there with the best, Amsoil, Royal Purple. Since Mobile 1 is almost 1/2 of what Amsoil cost, most folks go with Mobile 1. I really doubt there is going to be much difference in our cars. Going with a high quality oil filter is just as important. Doesn't do much good to have a long lasting oil if you have a cheap oil filter that is not keeping the oil clean. I go with either K&N or Amsoil filters.
I am also interested in your reasons for the mix and I also wanted to add that I hope you get home safe. (I noticed your location says Baghdad)
Thread Starter
Burning Brakes
Joined: Nov 2001
Posts: 1,149
Likes: 42
From: Minnesota
Originally Posted by JmpnJckFlsh
Folks out this way use Snake Oil. Snakes are plentiful in this area...you just need to find a good processor. 
snake oil you say? I hear that stuff has a lot of uses.
Race Director
Joined: Sep 1999
Posts: 12,434
Likes: 916
From: CONCORD NC
bottom line is this: In a healthy engine, with good oil pressure and propper bearings, there is very little mechanical friction. The metal parts (bearings, not rings and rocker etc) are not in metal-to-metal contact, but actually protected by a thin film of oil. While your pump may be only feeding 30-60psi of pressure, the actual journal pressure (due to the rotating of the crank etc) is actually over 1000psi. I actually took a class in college on fluid-film bearings, and the differential equations were way over my head.
In my opinion, any oil that meets the required specs, and is run in the normal temperature range (190-220 deg F) will offer adequate protection in a HEALTHY engine. If you are running higher or lower oil temps, it is worth considering an oil that has properties that match the 5w30.
For reference only, if you choose a 10w40 that has the same viscosity at 250 deg that the 5w30has has 200deg, AND you are doing events that keeps your car in the 250 deg range, you might want to consider the thicker oil. HOWEVER, you must them be especially carefull with cold startup, and make sure you reach adequate temps before reving or loading the engine.
In my opinion, any oil that meets the required specs, and is run in the normal temperature range (190-220 deg F) will offer adequate protection in a HEALTHY engine. If you are running higher or lower oil temps, it is worth considering an oil that has properties that match the 5w30.
For reference only, if you choose a 10w40 that has the same viscosity at 250 deg that the 5w30has has 200deg, AND you are doing events that keeps your car in the 250 deg range, you might want to consider the thicker oil. HOWEVER, you must them be especially carefull with cold startup, and make sure you reach adequate temps before reving or loading the engine.
Melting Slicks
Joined: Nov 2003
Posts: 3,375
Likes: 1
From: Northern CA
Originally Posted by JmpnJckFlsh
Folks out this way use Snake Oil. Snakes are plentiful in this area...you just need to find a good processor.
Last edited by xs650; Jan 17, 2006 at 11:50 AM.
Safety Car
Joined: Jul 2001
Posts: 4,456
Likes: 6
From: Spicewood, Texas, USA TX-Texas
Originally Posted by xs650
Processor?? Now you tell me you don't have to stuff the whole snake in the fill hole!
Le Mans Master
Joined: Aug 2000
Posts: 5,529
Likes: 1,943
From: Austin Texas
Originally Posted by BlackC6
Should I use a different weight for a track day or an HPDE?
To find the HTHS number for a given oil, look up the manufactures web site and download the materials data sheet for the oils in question. Yes, its a lot of work, and since oils have their forumulation changes several time a year, there is no other real choice--UNLESS you dorp over to Bob Is The Oil Guy and use the handy dandy compilation of the MDS sheets from many oil manufactures.
http://theoildrop.server101.com/cgi/ultimatebb.cgi