1953 Buick 40 Special, 263 cid/L8 with 99k miles, California car driven just 3-4 times per month. Which motor oil brand/type do you recommend? OE manual lists heavy duty MS SAE 20w. I intended to use a high mileage oil, but finding they are blend or full synthetic and much prefer a conventional.
If the motor is old (100,000 miles) then I would and did use 20W made from mineral oil. Anything lighter might cause smoke and rattling. Never use a synthetic or a high detergent oil in the engine, otherwise you'll find out in a hurry that you'll need a rebuild as it'll clean out all the crap that's holding your motor together.
Dad got the Roadmaster in 1970. He always put 30w Havoline in it. Since zinc is scarce in automotive oil now, I use Shell Rotella 30w for Diesel engines (it has zinc). I recommend 30w with zinc (or add STP oil treatment with zinc for oils lacking in zinc) I
Marc is agreeing with your 20w In on line with my phone right now. My phone doesn't show locations, if you're up near Marc in Latitude , I agree with 20w I'm in Alabama. I run 30w year round
I run Valvoline conventional with 1/2 quart of Lucas Oil Additive in original engines. Rotella has cut back on zinc & phosphorus. I use Brad Penn (para-synthetic) in race cars or hi-po rebuilds.
I'm reading a lot about the Rotella T 30W with mixed opinion. The benefit seems to be the ZDDP levels, but the diesel oil tends to be high detergent content. How much does the zinc content matter for the '53 straight eight? If using an additive, is there any concern with too much zinc and potential build up of deposits?
Before each oil change; I run a little Marvel Mystery Oil in the crankcase, to clean everything out. With the new oil, I add some STP oil treatment (blue bottle)
One has to stay on top of the ZDDP levels. The labeling tells little or nothing, one needs to take a look at the manufacturer's website .... They seem to change formula as quick as we change our oil
Okay; I agree with keeping up the ZDDP levels, and do supplement my 2 pushrod V-8s with it. Especially the Electra which has a recently rebuilt Nailhead in it. Once I do the Wildcat I'll use it in there too. I never put it in the 46 Super (248 straight 8) when I had it because the spring pressures weren't enough to warrant it, and the cam was well "seasoned" by that point. ZDDP is really crucial in fresh or recent rebuilds or performance motors with high valve spring pressures which really put the pressure on the tappets and cams. The old straight 8 with either type of lifter isn't quite there and may not benefit much from it, whereas the jury is still out on stock Nailheads. That said, it doesn't hurt to use it, even though on an older well used engine it's claimed that there may be no appreciable benefit. Any protection is better than none. A word about Marvel Mystery Oil; - if you haven't been using it since the start of that engine's life (either new or rebuilt) then you may want to avoid it for the time being until after the engine is rebuilt. It'll clean out too much, and take out all the varnish that's holding the bearings and rings together, especially if that engine hasn't been done in the past 30 years. Modern oils have detergents, and engines built within the past 20 years don't get as cruddy inside (my experience) as they used to, so you might get away with using Marvel, but I still wouldn't recommend any detergents, cleaners, or additives that claim to enhance or clean engines on any engine that is "older" (meaning not rebuilt) or has high miles on it. Buick inlines like to run cool; - they like nice thick oil. That engine has a hybrid oiling system, part pressure, part splash lubrication, but lower oil pressure than we're used to with modern cars. 10W-30 is nice, but it might be too thin at higher temperatures to be effective as a coolant, especially if you're in the South.
Unless your engine has been rebuilt to new specs, U need to use oil that is recommended for your car. U should add some ZDDP to the oil. U can buy mineral oil. Me, i would quaker state 10w20 if available although u could probably use 10w30. Add zddplus.
Good tip on the ZDDPlus. Researched it a bit more and placed an order on Amazon today. I had never heard of it and was about to go the route of a general additive with zinc. Thanks! The feedback received from all of you is equally appreciated! I am going with a Valvoline No-Detergent 30W. I'm thinking this is a best fit for the original straight eight that is still going strong and considering my location in the California SF Bay Area.
Another discussion: http://forums.aaca.org/f162/322-nailhead-inspection-363595.html I never add anything to the oil, but if it makes you happy then do it.
