Date: Sat, 3 Nov 2012 21:05:46 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: E
In-Reply-To: <20121103194810.IB02O.31324.imail@eastrmwml302>
Content-Type: text/plain; charset="utf-8"
Oil have been reformulated and better additives than zinc or other heavy metals are being used to do the job. There are still many engines that use cams rubbing on top of flat lifters. Most Diesel engines 2007 and later require lower zinc-ash oil formulations and some even require specific oils labeled for "Emissions System performance" This includes many diesel engines such as the Sprinter vans, Mercedes and VW. Most of these engines use catalysts, particulate filters, and they require the use of the Diesel exhaust fluid (DEF).
For the water boxer, while it is a flat tappet motor the rockers are low ratio the springs are soft, and the lift is modest. The original cams are hardened properly and we run at modest speeds. Cam and lifter wear is just not the issue that hot rodders used to see with racing springs, high lift ratios, and aftermarket cams that were only surface hardened. Most of us think of a collapsed lifter as one where the inside piston sticks down and lets the push rod/rocker go loose and make noise. Some of us have seen lifters wear or fail to the point that the top will actually collapse form wear and break through.
Due to the layout of the WB and add worn valve guides or intake valves missing the oil keepers it is common for these engines to pass some oil. Especially if the engines are overfilled. Using high zinc oils with this pass through is bad for both the catalytic converters and O2 sensors.
A number of the higher viscosity oils are still marketed for the collector and high performance car market. Castrol GTX 20w-50 and yes the Mobil 1, 15w-50 are promoted as higher zinc oils for these applications.
My Audi A8, Benz 600 SEL and 88 Fox get the Mobil 1, 0w-40 European formulae all year. The Vanagons get the Mobil 1 15w-50 except for the Red van if I am using it as a daily driver in winter. Then it too gets the 0w-40 as I only have a 30 minute ride to work.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Dave Mcneely
Sent: Saturday, November 3, 2012 7:48 PM
To: vanagon@GERRY.VANAGON.COM
Subject: E
Jim and others, my understanding is that the ZDDP concentration in modern oils is the same as it was in the 1950s (about 600 ppm), when it was introduced to protect the valve and tappet design then current. The concentration was increased later for a different reason, having to do with detergent properties of oil. Since catalytic converters have been required, the ZDDP concentration has been dropping to keep the converter functioning for 150k miles, but it is still adequate, with other changes in oil formulations, to protect the valves in older vehicles. In fact, if I am not mistaken, I got that information from the same GM author that your citation references.
I am stating this from memory, rather than from reviewing the original report I read right now, but I do think I am remembering correctly. The particular link you provided only gives data on oils, but the report I read (same author) discusses backwards compatibility of "star burst" oils (the modern service rated oils with the starburst symbol like), and the testing and results for oil service ratings
Basically, the report referred to the "myth" that the ZDDP levels in modern oils are too low to protect older engines.
Correct me if I am wrong. If so, I hope you will explain more completely than I have. mcneely
---- Jim Arnott <jrasite@EONI.COM> wrote:
> Jack,
>
> 5W40 Rotella T6 synthetic. That big Arkansas box store. $20/gal. And
> no.... the oil specified in the '84 owner's manual is no longer
> manufactured. As engines have moved away from a flat tappet design,
> manufacturers have changed the oil specifications. Typically removing
> the zinc (ZDDP) necessary for reduced cam wear in our engines. Diesel
> spec oils have the maximum in currently produced lubricating oil.
> Rotella T6 synthetic has the highest concentration of all current
> mass- produced motor oils.
>
> <
> http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Numbe
> r=2330040#Post2330040
> >
>
> Jim
>
>
> Kindness in words creates confidence. Kindness in thinking creates
> profoundness. Kindness in giving creates love.
> --Lao Tzu
>
> On Nov 2, 2012, at 9:27 PM, Rocket J Squirrel wrote:
>
> > I'll need to bust out the owner's manual to see what they recommend
> > for the Cold Season. Nights down to mid-teens (F), days up to 40s.
> > Is this ca. 1984 manual still my guide to all things engine oil?
> > --
> > Jack "Rocket j Squirrel" Elliott
> > 1984 Westfalia, auto trans,
> > Bend, Ore.
--
David McNeely
