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| | | Forums66 Topics128,014 Posts1,055,331 Members48,419 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Feb 2001 Posts: 1,094 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,094 | Hard to find 30 w oil around here. All I seem to find is shell Dello. Is this ok for a 261?
Tommy 59 apache 1/2t 261 short stepside | | | | | Joined: Aug 2011 Posts: 835 Shop Shark | | Shop Shark Joined: Aug 2011 Posts: 835 | Why not use a good multigrade oil?
Kurt | | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | Dello is a 15W40 viscosity. It will work good in your climate. They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Apr 2005 Posts: 1,971 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 1,971 | | | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | I just bought this oil this afternoon, Checked my local Carquest, Napa, Oreilly auto. No one had it on the shelf. Went to Walmart they had the gallon jugs on sale for 12 bucks, also had quarts on the shelf. Orieily did have the fram C4P oil filter I needed. Im using that oil on a 235 | | | | | Joined: Jul 2011 Posts: 10 New Guy | | New Guy Joined: Jul 2011 Posts: 10 | 15W40 is usually for diesels it may be a little thick for a 235. if you are looking for a straight 30W you can try a harley dealer for it. | | | | | Joined: Oct 2010 Posts: 91 Shop Shark | | Shop Shark Joined: Oct 2010 Posts: 91 | i am using valvoline VR1 oil which has the zinc in it that our flat tappet engines should have.It is recomended on Patricks website wich is in the links on this site.I get it at NAPA. | | | | | Joined: Aug 2011 Posts: 18 New Guy | | New Guy Joined: Aug 2011 Posts: 18 | Most "Tractor Supply Stores" have straight 30W motor oil in stock | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Tommy,
What year and size engine are you referring to?
GM recommended multi-viscosity oils for 1954 and later 235/261 engines (and also recommended single weight oils).
These would be fine: 10W-30 10W-40 15W-30 15W-40 and even 20W-50 would do no harm to a 1954 and later 235/261 engine
Diesel oil with ZDDP would be fine.
| | | | | Joined: Feb 2001 Posts: 1,094 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,094 | Tim,
I have a 59 261. I sure I've always put 30w oil in most of the vehicles I've owned up until maybe 10 yrs ago.I realize technology has changed over the years and the oils may have improved. I had quite a few 325,230,250 6 bangers over the years and always did 30w, heck thats about the only thing that was available other than 40w and harley d 50w. I just noticed the other day when looking for oil that every place I looked there was no 30w.
Tommy 59 apache 1/2t 261 short stepside | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Tommy, 1959 Chevrolet Truck Operator's Manual - Lubrication GM's specification/recommendation of multi-viscosity oil started with 1954 engines (single grade oil was also specified/recommended). Of course, the benefits of multi-viscosity oils were the combination of the "easy starting characteristics and . . warm weather operating characteristics". Nonetheless, if you want 30W oil, have you checked NAPA and Walmart (they have both detergent and non-detergent 30W oil in our area)? | | | | | Joined: Jun 2008 Posts: 1,388 Shop Shark | | Shop Shark Joined: Jun 2008 Posts: 1,388 | Our Walmart carries it, and so do the big auto parts places. Here, you've got you pick of non-detergent, or detergent even. Life is good in Brentwood. | | | | | Joined: Mar 2008 Posts: 1,775 'Bolter | | 'Bolter Joined: Mar 2008 Posts: 1,775 | I've been doing some research lately and the oil that is labeled for ATV or Air cooled engines is a good alternative. They don't have all the emmission standards that automobiles do now, so they still run plenty of ZDDP in the oil. | | | | | Joined: Dec 2001 Posts: 14,522 Moderator: Welcome Centre, Southern Bolters, Legion Hall | | Moderator: Welcome Centre, Southern Bolters, Legion Hall Joined: Dec 2001 Posts: 14,522 | Advance Auto stocks 30 wt. Shell,Penn,Castrol and the standard store brand and one other one but can't remember it. They have both, ND non detergent and HD high detergent. | | | | | Joined: Feb 2000 Posts: 5,192 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 5,192 | If this is a old engine with lots of miles on it, you have no need for the high zinc levels in race oil or diesel oil. You cam is well broke in and the valve springs are pretty weak compared to high quality race springs. So any oil oil you wish to run will work fine. 10w30 is the same as straight 30 once warmed up but will flow better when cold so you have more lube and less drag at first fire. I run 5w30 in my 250 and dad runs 5w20 in his race motor (469 ci Pontiac), we like the less wear and tear on oil pump drives and gears. Thick oils like 20w50 just cause stain on the pump drive and rob horse power.
Joe | | | | | Joined: Oct 2006 Posts: 1,847 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 1,847 | about the only reason to use straight weight oil is momentum from the past, even Caterpiller recommends 15/40 now. You will have to ask Grig about Detroits, I know 15 years ago they were recommending non-detergent 40 weight, but maybe they have caught up with the rest of the world by now. I have been using 5w30 for about 5 years now just because thats what all my new cars are using it seems to be working fine. the engine was rebuilt in 1979, form your own opinion. | | |
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