The Stovebolt Site Forums The Shop Area Engine Shop Recommended engine oil

I just returned from a local car show in my 1948 Chevy 3100. While I was there, I received a 20 minute plus talk from an elderly gentleman, that retired from an engine oil manufacture I guess, that I should be using an oil with higher zync content or I would tear up my 216. I am the first to admit that I am no engine expert on these type of engines and what they require. I am sure everybody has an opinion on the subject but I would like to hear some advice please.

Unless you just rebuilt the engine, any decent quality oil is fine. I, too, have a '48 3100 and it's been running on everyday oils since 2008 with no problems.

The added zinc is helpful in seating new valves.

I for one think it is snake oil. If it were that important than almost every engine should need it, except maybe with a roller cam.
A case could be made for using it if very strong valve springs are used.
I never use it and have had no failure on the numerous engines I have rebuilt.

My 250 is a newer engine then yours, but still 45 years old. It has had so many different grades and types of oil I lost count and still, it runs strong with no problems. Right now it has 5w20 in it.

If this is a used, stock engine, run any oil like, 10w30 or straight 30, 40 weight if its real hot where you live. The additives are for rebuilt engine with new cams or engines with very high lift cams and big valve spring pressures.

Joe

The deal with roller cams is the parts have to be extremely hard, because when you get the cam follower on the pointy end of the cam there is an extremely small contact area. I also have a feeling that there is a lot of metallurgy taking place with the inverted bucket technology. There needs to be a certain amount of phosphorous (the part of ZDDP that is what we are really after) But after reading several thousand pages of reports, I still have no more of an idea of what is real or not. I do know it probably won't hurt anything to have a certain amount of ZDDP in your oil. Too much is just as bad as not enough according to several of the reports. However the major need for elevated ZDDP levels is mainly during cam breakin, GM uses an assembly lube which IS the supplement. You may or may not need it, but given the amount of money I put into my engine, I will just go ahead and spend the extra $20. Yeah I may be lining the pockets of some scammer, but, I have wasted a WHOLE LOT MORE money on stupider things. And I give the government way more money than that, and I am a whole lot less satisfied with their performance than I am with my engine.

Amen to the government wasting! I am not happy either.

My rules for the additive is valve spring pressure and cam profile. If you can't move the spring just a little by prying on the rocker arm, the oil should have some, and if the cam is not a stock grind, the oil should be doctored. The bigger the cam, the more it gets. New cams get the full treatment. $20 on top of $1000's doesn't seem like to bad of insurance.

So many cars and trucks are modified, one set of rules will not cover all of them. Most will error on the safe side and run the best oil with the most additive. Then the are the few that use the cheapest oil made and never have problems. So who is right?

I for one have seen aftermarket cams go bad and had to deal with the clean up and rebuild, but I have yet to see a stock, well used engine have a cam go bad due to oil. A stock 216 or 235 may have 70 to 90 psi valve spring, most aftermarket cams that need additive have springs in the high 200 psi range or higher and this is where most of the confusion comes from, grouping all engines together.

To each his own I guess,

Joe

because when you get the cam follower on the pointy end of the cam there is an extremely small contact area

Roller cam lobes don't have a pointy end.

Originally the ZDDP was .03 to .08% .. but oil co's realized that higher ZDDP levels were a cheap way to reduce oxidization (thickening) so they jumped the ZDDP level to .010 and beyond. But tests showed that ZDDP above .014% would eat metal.

So they reformulated the oil and ZDDP levels dropped from mid teens to low teens. Once the EPA sought to reduce ZDDP as it harms catalytic converts it went below .010%.. which was where it was originally was to being with.

If you run a super whumpa-whumpa double valve spring motor with cam profiles that look like squares then yeah, more ZDDP can help (but again, to much ZDDP will eat metal).

Any modern API oil will be fine. originally the oil was 20 or 30 weight... but a good multiviscosity oil like 5W20 may be easier to find.

the pointier end, and yes a roller cam has a pointier end, pointier than the heel of the lobe, it isn't just a perfect circle mounted off center.

Been using Valvoline 30 All Fleet Plus (made for diesel engines) in my 235 since 1986 rebuild. Higher Zinc and Phosphorus content than auto oil. No smoking, no oil burning, good oil pressure - 70,000 miles on engine. Oil is rated CF-4, I believe.

Maybe the posts above addressed it - and I missed it: I have a rebuilt 216 in my 52 Chevy pickup. Should I use detergent or non-detergent oil? Thanks. Bob

Detergent.