should I stick with M1 10-30?

Messages
1,153
Location
Washington
I currently run M1 10-30 in my 2001 2500HD with the 8.1 liter engine. I tow our 6000lb trailer a few hundred miles per month,but most of my driving is around town 3-5 miles at a time. I'd like to stick with a synthetic,but I don't like how thin the M1 seems. My manual says 5-30 or 10-30 is acceptable. Does M1 make an oil that is a bit thicker,than the 10-30,but is still ok for my truck? I live in W.Washington,and the temps rarely go below 32 even in mid-winter. Thanks for your help.
 
Messages
33,973
Location
Southern NJ
TsoA hit it. Just add a qt. of 15w-50 if you want a thicker oil. Most likely, the 10w-30 by itself is more then adequate. Don't focus so much on this "thin vs thick" talk. While it raises some questions, there is no proof that it really makes a significant difference. BTW, does this truck require a Diesel oil? If so, try Delvac 1 or Amsoil 5w-30 HDD. Both oils are excellent. [ August 23, 2003, 11:01 AM: Message edited by: buster ]
 

Al

Messages
19,154
Location
Elizabethtown, Pa
quote:
Originally posted by TSoA: Just mix in 1 or 2 q of M1 15w-50.
I agree here a 50%mixture gets you to 40 wt range. A 30% solution which might be better gets you to an upper 30 wt. I'd go with that solution. I would use the 10W-30 vs 5W stuff in this "witches brew" As was mentioned 5W-40 Devac 1 can't hardly be beat.
 
Messages
9,448
Location
USA
I agree with Buster, Tsoa, and Al. The 15W50 10W30 mix is common. Alot of diehard Corvette and Camaro owners do this. I am trying it right now in my Toyota.
 

Stewart Fan

Thread starter
Messages
1,153
Location
Washington
My truck is a gasser,and uses 6.5 quarts at a change. I use 7 quarts,and it reads to the top of the cross-hatch on the dipstick. So you think the best bet is 5qts of 10-30 and 2qts of 15-50? Do GM reccomend 5-30 because of tighter tolerances in the engine,or is it just for added MPG?
 
Messages
36
Would recommend you do an oil analysis for your particular engine and get advice from other owners of the 8.1.
 
Messages
6,388
Location
Washington St.
quote:
Originally posted by Al:
quote:
Originally posted by TSoA: Just mix in 1 or 2 q of M1 15w-50.
I agree here a 50%mixture gets you to 40 wt range. A 30% solution which might be better gets you to an upper 30 wt. I'd go with that solution. I would use the 10W-30 vs 5W stuff in this "witches brew" As was mentioned 5W-40 Devac 1 can't hardly be beat.

Mixing different viscosity oils does not give the arithmetical average viscosity. Some one suggested that the molecule size if each oil viscosity be represented as different sized balls. Say 30wt oil is represented as golf balls and 50 weight oil is represented as soft balls. When mixed you do not have base balls, you still have golf balls and soft balls. It's somewhat the same when mixing oils. You have a combination of smaller 30 wt oil molecules and larger 50 wt oil molecules, and no medium-sized 40 wt oil molecules. If you want a different oil viscosity, buy it. Or use a product that's made to do the job such as Schaeffer's #132 oil treatment. Look at page 9 of this link for a chart showing how to determine the resultant viscosity when mixing straight wt. oils...multi-weight oils are more difficult to determin. http://www.ethyl.com/products/la/handbook/Viscosity.pdf Ken [ August 23, 2003, 05:56 PM: Message edited by: Ken2 ]
 
Messages
254
Location
Calgary AB
Just look for a 5 or 10w30 marketed as a Heavy Duty Motor Oil. These are generally blended to the high side of SAE 30, usually around 12 cSt @100°C. I don't believe this M1 is marketed as a Heaby Duty Oil rather a Passenger Car Motor Oil.
 
Messages
3,216
Location
BC, Canada
Stewart from Everett; I've owned quite a few BBCs and all of them have used a little oil. I don't think you could go wrong with an HDMO 15W40. My opinion, and everybody has one just like....well you know the rest of the story The light weight VS heavy weight engine oils question: Buster and a few others may someday be elevated to gru status, not buying into the heavier is better mentality that some of have real bad. Light weights have their place, and I'm sure the oil companies and auto makers are going to make sure they eventually succeed. The light weights are slowly gaining acceptance. Its been done before with 5W30 and before that with the first multi-grades. History does repeat its self. But not in your siamesed cylinder BBC with its 1965 design and poor rod oiling. Buster is correct about oil flow being so very important through out his posts. No statment is more true than with the BB Chev. Never, did I say never yet? Work your big block hard until the engine is warmed up. Starting with #2 rod bearing, #6 exhaust cam lobe and on from there you will wipe out your engine in no time at all. The light weights idiot-proof that habit people have of jumping into their vehicles and hitting 4,000 rpm when the engine starts then roaring off into the morning I-5 traffic. Do that with your BB Chev and you will be picking your crank up off of the ground, 0W20, 5W30 or not. Some of those 10W30 HDMOs are quite bullet-proof and make a good BB oil from November to March. In places like North Dakota, Minnisota, Wisconson, and most of Canada I wouldn't even drive a BBC powered vehicle during the winter Unless I had no other choice. That is where the use of a 5W20, 5W30, 5W40, 0W40, or 0W30 engine oil would be not only a wise decision, but necessary for the survival of any engine including the mighty Ford, Chev, and other big block V-8s. Buster is correct in his posts when he repeats that light weights are not a problem in engines that are designed for them or otherwise recommended by the manufacture. All others may use them at there own risk. A few others made the point being that the heavy weights have proven themselves over 10s of years. It is up to the light weights to prove themselves now. Not the other way around.
 

Al

Messages
19,154
Location
Elizabethtown, Pa
quote:
Originally posted by Ken2: Mixing different viscosity oils does not give the arithmetical average viscosity. Look at page 9 of this link for a chart showing how to determine the resultant viscosity when mixing straight wt. oils...multi-weight oils are more difficult to determin. http://www.ethyl.com/products/la/handbook/Viscosity.pdf Ken
I certainly agree that its not an arithmetic average. I was basing it on a mixture that I actually used. a 30% mixture of the 15W-50 with 10W-30 produced a viscosityt of 11.25 cSt. Now understand that this was after one year and 5K miles so there could have bee shearing or thickening. And BTW I have seen that graph before and just couldn't figure it out. Tell me what you get by mixing a 50% mixture of 10 cSt oil and 18 cSt oil. That would give a 50/50 cSt (when hot) value for mixing the 30 wt. and 50 wt in equal parts. [Frown] [ August 23, 2003, 08:26 PM: Message edited by: Al ]
 
Top