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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Nov 2009 Posts: 38 New Guy | | New Guy Joined: Nov 2009 Posts: 38 | Need to change the oil in the old “54” 235, what is the recommended oil for these old motors?
| | | | | Joined: Aug 2005 Posts: 6,377 Ex Hall Monitor | | Ex Hall Monitor Joined: Aug 2005 Posts: 6,377 | I use 15w-40 and have spoken with a lot of folks who use 10w-30 regularly.
Save a life, adopt a senior shelter pet. The three main causes of blindness: Cataracts, Politics, Religion. Name your dog Naked so you can walk Naked in the park.
| | | | | Joined: Jul 2008 Posts: 1,262 Shop Shark | | Shop Shark Joined: Jul 2008 Posts: 1,262 | Be sure to pick an oil that is designed for a flat tappet cam motor. The additives that help with wear aren't good for emissions, therefore the manufacturers of the oil keep putting in less of it. I just changed the oil in my (4) old flat tappet motor vehicles and used Valvoline VR1 Racing Oil. Because it is "racing" oil and designed for high lift cams that need good lifter / cam lubrication it has the additives you need. Here is a link to a thread that talks about this more in depth: http://67-72chevytrucks.com/vboard/showthread.php?t=381780Note: Some of the oils on the list are tough to find. Good Luck! John
Last edited by Hot Rod John; 11/08/2011 12:58 AM.
| | | | | Joined: Jun 2005 Posts: 388 Shop Shark | | Shop Shark Joined: Jun 2005 Posts: 388 | A quick search on "oil" revealed at least a dozen threads in the past twelve months on the topic of what type or grade of oil to use in a Stoveblolt. Of the dozens (perhaps hundreds)of recommendations, it seems that 10W-30 came in first with 15W-40 (usually Rotella) a close second. There were also many votes for straight 30 and 10W-40, with a smattering (one or two) of votes for 20W, 20W-40, 20W-50, 5W-30, and Mobil 1 15W-50. There was one recommendation for a blend of 3 quarts of 30 and two quarts of 10W-30. I may have missed a few. I did not see any votes for 20, but there still seems to be some confusion over when to use, or not to use the "W" after the grade number. There were many (but not quite 50%) recommendations for a ZDDP additive, even after break-in.
I only noted about three recommendations for a non-detergent oil, with several for synthetic.
I use 15W-40 Rotella, with EOS, in my 261.
Hoyt | | | | | Joined: Oct 2006 Posts: 1,847 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 1,847 | Ihave been researching the zinc dilemna for a while now, and what I did find out is racing oil has low levels of detergents due to the fact the detergents reduce the shear strength of the oil. So if you do use a racing oil you need to change the oil more often. I also found that the SM oils have a maximum of .08% of zinc, which would be fine for lifter foot pressures of 600 pounds. (which was the limit of the testing device being used in the particular test) However this is the MAXIMUM level of zinc allowed and some are down to 04% which isn't adequate for a flat tappet cam. I have only been taking notes of studies done by reputable agencies, such as the fella from GM that wrote a rather informative article, who it turns out is nearly without peer in the lubrication world. But what ever the case. about the only consistency I could come up with was around 1200 ppm (where that lies in percentage I don't know, that was another problem I was having, half the studies were done in PPM and the other half in percentage)of zinc should do you just fine. There has been sqawking about just using oil for diesel engines, that has its problems as well, since the oil is formulated for diesel engines after all. (one issue is the extremely high level of detergents) But it does have adequate zinc levels for now. but that will probably change soon as the EPA is requiring catalytic converters on trucks. (that is why I got laid off from Kenworth, no one was buying the new trucks with all the emission junk on them) what ever the case you need an oil with at least .08%/1200 PPM zinc and since everyone has used pretty much every weight oil known to man with what seems like the same results. just go ahead and use whatever you want. (just to add to your list, 5w-30 is what I have been using for the last 3 years in my 216) Just for fun, start looking at oil formulation. That is some black science, look up the various ratings SL, SM and what have you and it gives you the min/max of various components, I'm thinking you could spend at least two years in college learning all this nonsense. What ever the case there are a few companies making oil for classic cars, castrol is the only one that comes to mind right now. As far as lubricity, there will be arguments of course, but synthetic is by far superior to your standard mineral oil based oil. Oh and one last thing, the zinc and phosphorus will be somewhat relative as the P in ZDDP is phosphorus. which in itself is an EP additive, there is also moly and boron being phased in, to replace the zinc (converter poison)
Last edited by brokenhead; 11/08/2011 1:05 PM.
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