What is the best oil to use on a pre-war Buick

[25Buick47]

The shop manuals call for non-detergent 30 weight oil? Can I use 10W-30 in my 1925 Master and 1937 Century? Time to change the oil in both for the up coming season.

[Guest ZondaC12]

well what ive been told by all the experts here is if youve got an original never-torn-apart engine (like mine) you HAVE TO stick with non-detergent or it will loosen up the gunk and clog a passage and starve something of oil.

but with a brand new rebuilt engine, go ahead and use the modern stuff.

[Mark Shaw]

Zonda is quickly becoming an expert by watching this forum. 250 wt tranny gear lube will also help you shift easier in your older car. The heavy lube helps to synchronize the gears more quickly.

[Guest brh]

When dad and I had the engine rebuilt in a 1934 Olds the engine guy told us point blank to use the cheapest non det we could find. Reason being was the engine did not have an oil filter and the engine was designed for the crud to settle on the bottom of the pan to be drained. A detergent oil cleans but holds the crud too and without a filter it pumps all that crud around. This was many years ago, don't know if its true today.

[Guest brh]

Could I have used the word "crud" a few more times??!!

[Old26Buick]

I'm rebuilding my 26 Buick engine and the fellow that is doing the crank and babbitt work only uses 15-40 in all the engines they do. Has had very good luck in the last five years.

[Guest tin knocker]

I wouldn't worry about detergent oil use without a filter. In years past I've had two VW beetles of which neither had an oil filter and they were designed this way. I put well over 100,000 miles on each and neither used oil. I drove one with 110,000 miles on it from northern Wisconsin to southern California and it used less than a quart.

Rollie

[Mike Cullen]

Don't sweat the detergent/non-detergent question. "Detergents" in oil tend to keep particulate matter (technically called crud) in suspension. Without oil filters, as many of our relics are, the crud is recirculated through the engine. Theoretically, detergent oils will break loose any accumulated sludge over time and circulate it through the system. We tend to change our oil so frequently that the suspended crud is removed better than with longer intervals and a full flow filter. Older engines also tend to have looser tolerances on the bearings, add that to the better lubricating qualities of today's oil, (pre-war motor oil was pretty much crap) and oil related failures will be very unlikely. If you have broken or defective parts, rattling and scrubbing up bits of metal, etc, you will have problems detergent or non-detergent oil. If your car calls for SAE 30 oil, and it hasn't been rebuilt in the last 20 years, 10W-40 is fine. If you are in cooler climes and would run a straight SAE 20, use 10W-30. If you have a tired old loose engine, use 20-50, it will build a heavier film between parts while running and help keep your pressure up and rattles down. If you rebuild your engine to tight modern type tolerances and use modern seals, go ahead and use lighter oils, but using synthetics (IMO) is a waste if money, again, we tend to change our oil so frequently that the advantages of synthetic oil don't justify the cost. Remember, even today's cheapest crap $0.75 per Qt. discount store oil is still far superior to even the best oils of 50 years ago.

I recently stripped a V8 21 stud Ford engine. There was 3/4" of sludge everywhere in the lifter valley, oil pan, timing cover, everywhere! but every bearing surface was fine, the fiber timing gears were OK, the oil rings were sort of sticky in the pistons, but the cylinders were in good shape, this engine may not have been run in 40-50 years, but even with the crap oil, sludge, and alcohol based anti-freeze, the loose bearing tolerances kept enough oil flowing to keep it from grinding itself away on it's own "crud" (I had almost forgotten how sludged up engines always were when you tore them down back then, I haven't seen an engine so sludged up since the late 60s or early 70s)

[Guest Straight eight]

There is more to this question than detergent vs non detergent. We now have oil being reformulated without the friction reducing additives that kept our overhead valves operating without wear. To make a long story short it appears that truck oil Shella Rotella, and other similar oils still have enuff additives for the time being to keep these old engines running, that have been rebuilt. It is a detergent, so this applies only to rebuilt engines that have used detergent oil. Elsewhere in these pages is more info on what they have done to engine oil to keep our modern iron running, but to the detriment of our old stuff. <img src="http://forums.aaca.org/images/graemlins/shocked.gif" alt="" />

[Mike Cullen]

Here is a long thread on the LCOC board concerning the reduction/ elimination of ZDDP and its effect on our older flat tappet engines. If you are using the newer spec oil with ZDDP removed there are additives that can be added, or you can still use the diesel rated oils for now.

http://www.thelincolnforum.net/phpbb/viewtopic.php?t=18359

[Guest 1937RHDNZ]

Like many before me, I have also asked this question. After my own research and reading many replies, including other forums, from high tech engineers to the bloke who has done it his way for 60+ years, I now know the answer. And the answer is; There is no answer, or subtitled "Any oil is better than no oil"

I hope that helps.

Cheers Neil

[old-tank]

http://www.englishautosociety.com/articles.html

Some of the same info, but the conclusion at the end suggest that Castrol 20w-50 and 30w are suitable for these old cars...

[Guest brh]

Thanks for my chuckle for the day!!!! Knowing I have correctly defined stuff in the oil using the termonology "crud" cracked me up. I needed this one today. You do bring up a good point on changing oil, we ran the cheap stuff in a 71 Pontiac changing oil often. 175,000 miles later, she would start first crack out of the barrel every single time. Never had to tear down the engine, kid next door killed her.

[Gene Brink]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Here is a long thread on the LCOC board concerning the reduction/ elimination of ZDDP and its effect on our older flat tappet engines. If you are using the newer spec oil with ZDDP removed there are additives that can be added, or you can still use the diesel rated oils for now.

http://www.thelincolnforum.net/phpbb/viewtopic.php?t=18359 </div></div>

Was not the Lincoln forum but was reading someplace that the elimination of zinc as an additive is not great for lifters all the old Buicks have (roller lifters are the reason it was dropped - no need for the protection it adds) but the article said racing oils still have the additive so there is another option.

[Guest ZondaC12]

re: these additives---

does non-detergent 30w NOT have these? if i should switch to something else, whats best? (i dont think i want to read through that long lincoln forum thread)

ill certainly switch if i should, now, so its done before the driving season starts! from this thread ive seen diesel motor oil, and racing oils. where can i get these racing oils and how do you know thats what you're getting? i take it you cant find them at advance auto? obviously diesel oils you can.

EDIT---well i bit the bullet and read the friggin thing.

sounds like its all in the API code listings on the back. anything "less" than CJ or SM is good, it seems in terms of ANY oil. as long as the codes are alpabetically before CJ or SM is has the ZDDP you need. so i guess what youll likely find is SL, and CI. thats fine. next time im at the parts store ill see what i can find. im switching!

alternatively does that "CD-2 oil additive" have ZDDP? could i just dump that in my non-detergent 30w?

[Guest unclefogey]

I thought about passing on this thread when it appeared because it represented the almost quarterly posting of the never ending question of what oil to use in our low tech engines. Was I surprised, as the subsequent postings appeared, that it had important timely information applicable to the enormous expense of having the 248 in my '41 rebuilt.

When I picked the car up a month ago, my last question before I drove away was what oil I should use, both manufacturer and viscosity. I asked if 30W had to be used and was told any good grade of 10-30W would be correct. The oil should be changed at 500, 1000, and 1000 miles, and then at "normal" times. The 10-30 was good news because it is what I use in my Ranger, Suburban, and all the other vehicles I change oil for other people. I celebrated by buying two cases of Valvoline 10-30 that had a $10 rebate. As a note, my rebuilder is a member of AERA.

Then this thread appears. <img src="http://forums.aaca.org/images/graemlins/frown.gif" alt="" /> I called my rebuilder and asked if he had heard of the problem with flat tappet engines and the new grades of oil. He said that he hadn't. I asked him if he had seen the AERA tech bulletin cited in the Lincoln forum. Again he said no. Asked if he could check with AERA and find out what was going on, which he said he would.

In the meantime, I panicked, because I am not turning the key, or stepping on the gas pedal to engage the starter until I get an answer or get my hands on some additive to add to the oil. I went to the Crane Cams website and ordered some (3) of their engine breakin additive, for the oil presently in the crankcase and the next two changes.

Today I spoke to my rebuilder and he said that the AERA tech advisor he spoke to said that AERA hadn't really heard of any problems with rebuilt flat tappet engines and the new oils. He did ask the tech advisor to send him the supposed tech bulletin about the problem, but as of today, had not received it. He said that tech advisor suggested that if I was concerned, I should add the GM EOS additive to the oil, which they always add to the racing engines they rebuild. So flat tappet rebuilds get no additive, but roller tappet racing engines always get an additive. We ended the conversation with him saying that he would try again to get a copy of the AERA tech bulletin, if it exists.

I know nothing about what might be contained in CD-2. I looked at container of Valvoline 30W I bought two years ago for my first oil change after I bought the car and it was SM rated. Last year I went with the lower price spread for an oil change because she was burning and leaking so much, and bought a CITGO (Ya, Hugo Chavez's brand) 30W that was SL rated. All the Valvoline 10-30 is SM rated. Now I know what I will do with the gallon of Rotella I had left over after I traded my 6.2L in 1999. <img src="http://forums.aaca.org/images/graemlins/smile.gif" alt="" />

If the AERA bulletin ever shows up, I will summarize it here.

John

John