7 August 2013

Oil for Your Classic: What you need to know

If you’ve spent any time reading or listening to stories about changes in oil over the past decade, you’re probably confused, scared, or both. The issue is that changes in oil formulation have reduced the amount of a Zinc additive (zinc dialkyldithiophosphate, ZDDP) and often increased the amount of detergent in modern oils. For awhile there were few oil products available for classic cars, but today, several companies have come out with products specifically designed for older cars.

The primary issue is that the phosphorus in ZDDP is hard on catalytic converters, and exhaust gas recirculation (EGR) systems perform better when there are more detergents and dispersants in the oil. So ZDDP has been reduced, while detergents and dispersants have been increased in modern oils.

For our classic cars, these changes can have a compounding effect. ZDDP is added to oil to coat and protect high-wear surfaces, like the solid-lifter valve trains featured in many classic cars. Increased detergent levels tend to wash away the little ZDDP that is still attempting to protect our valve trains. Finally, modern oils have more friction modifiers to increase fuel efficiency, which can lead to reduced oil film strength and damage parts.

When these oil changes first started occurring, the primary alternatives were diesel oils or racing oils, which contained higher levels of ZDDP than conventional oils. Each of these presented their own problems. Diesel oils have plenty of ZDDP, but unfortunately even higher levels of detergents than conventional oil. Race oils have a good balance of ZDDP and detergents, but lack the anti-corrosion additives that are critical to keep internal corrosion low in little-used classics. 

Today, several specialist oil companies have come out with oils formulated for classic cars. These oils balance the ZDDP and detergent levels adequately and include appropriate corrosion inhibitors to keep our engines from damage whether they’re running or in storage. 

While each specialist company has its own reason for getting into the classic car oil business, one of interest is Classic Car Motor Oil. The development of this product was driven by the Indiana Region of the Classic Car Club of America. Club members approached the D-A Lubricant Company near Indianapolis about the problems of modern oil in classic cars, and D-A worked with them to develop and co-market a specific blend of oil for Classics. Classic Car Motor Oil is now available in sizes from the quart to the case to the 55-gallon drum for enthusiasts with classic cars. The work from this club and this company show that grassroots efforts can yield great results.

While there still may be some confusion about oils these days, it’s reassuring to see that the marketplace is responding with products that will keep our classics living on. Make sure to consider your oil options next time you service your classic car.


Classic Car Motor Oil Company

Driven Racing Oil

Brad Penn Oil

54 Reader Comments

  • 1
    jOHN eRICKSON iDAHO fALLS ID August 15, 2013 at 13:11
    Chevron delo 15-40 le and ursa 15-40 botht cj4 oils that can be used in both new and old vechicles. The chevron 15-40 motor oils have not reduced the amount of zinc in the oil. Still at 1300 parts per million zinc. Where the 5-30, 10-30, oils are down to 86 parts to million. The best thing about chevron out on the road it is available everywhere. Plus you get into these specialties oils and they can be expensive for what you are getting.so chevron will still be my choice for my classic cars.
  • 2
    jimpassi United States August 15, 2013 at 13:23
    to me it dident say much. what are our choices i dident see any. zmax & royle purple the only ones i know about & i guess any syn.oil
  • 3
    laguna mike Austin TX August 15, 2013 at 13:36
    I am using 20/W50 Valvoline Racing oil. I understand it has ZDDP. Does anyone have any comments.
  • 4
    RICHARD SANDERS DAMASCUS, VA August 15, 2013 at 14:24
    i would be interested in getting some 20w-50 for my MG collection.
  • 5
    David Beyer Ft.Myers,Fl. August 15, 2013 at 14:25
    Amsoil has produced high zinc-high phosphorus oil for a few years called Z-ROD. Of course being a synthetic it will stand up to any thing you can through at it. Z-ROD comes in 10w30 and 20w50. For more info go to www.amsoil.com
  • 6
    Morgan Bell Naselle Washington August 15, 2013 at 14:29
    Do you know about Amsoil "The First In Synthetics" offers "Z-ROD" a high-zink,high-phosphorous formulation engineered specifically for classic cars and performance vehicles with a unique blend of rust and corrosion inhibitors to ensure maximum protection during long-term storage? As dealer #1123639 I feel obligated to have you well informed on the lubricant market we offer. Respectfully, Morgan Bell
  • 7
    ted rissell Oakland, MD August 15, 2013 at 14:46
    After a conversation with a technical guy at STP,I was assured me that although he would not give out the proprietary recipe of STP, , that I would have the proper amount of ZDDP in 10/30 Penzoil if I used STP as directed.
  • 8
    Chuck Daglow Jonesville Mi August 15, 2013 at 14:49
    The best option I have found is to use Motorcycle oil. It has a higher zinc additive. And it also has the sf rating. The newer oils have an sm to sn rating and it is better for the newer cars. I also add about 4 ounces of two cycle oil to the gas for a twenty gallon tank or 2 ounces for a ten gallon tank like my mustang.
  • 9
    wayne rich shinglehouse pa August 15, 2013 at 15:02
    I have been using penns oil, for as long as I can remember inall my classic cars. with blower mtrs. ect with great performance...
  • 10
    Patrick Heinz United States August 15, 2013 at 15:09
    BRAD PENN has been good for my 67 S.S. 396. I wouldn't hesitate to recommend it!
  • 11
    Robert Atl. August 15, 2013 at 16:10
    You can also use Shell Rotella 5-40 Synthetic or Shell Rotella 15-40 regular oil. Plenty of Zinc (1200 ppm) in them. .
  • 12
    Larry B. PA August 15, 2013 at 17:13
    The article says flat tappet motors. My '67 AMC 343 uses hydraulic lifters, and I have been using Castrol GTX 10W-40 for years and haven't had any problems. I used the same oil in my '57 Rebel which had solid lifters and didn't have any problems, either. I think the Rebel's engine was original.Just my .02
  • 13
    Ben Leone Stratford, Ct. August 15, 2013 at 17:15
    Oil is oil. I use full synthetic 10/30. I use whatever is on sale at Walmart. Usually Penzoil. I change it once per year in all five of my cars. Thirty years never had an issue, Thank God!
  • 14
    Steve Bagatti Iowa August 15, 2013 at 18:25
    Brad Penn was recommended to me for my 79, L-82 Corvette. It's worked for me and the $7.50 price tag is cheap insurance.
  • 15
    BILL NEW YORK August 15, 2013 at 20:19
  • 16
    Kerry Pilling Washington state August 15, 2013 at 21:08
    Red Line makes oil and gear lubes for older and classic cars. Good stuff, check them out for yourselves. I think you can find them online pretty easily.
  • 17
    Jim Perry Larsen, WI August 15, 2013 at 21:55
    If one looks at the product information sheet for Mobil 1 20W-50, I believe you will find that it contains all the ingredients to keep flat tappet motors happy.
  • 18
    Larry J Universal City Tx August 15, 2013 at 22:45
    What oil should I use in 65 mustang 289 high performance and where is it available at? Thanks
  • 19
    al zim FT.Worth Texas August 15, 2013 at 10:58
    Ever since I started in the car repair business 51 years ago the first shop I worked in used Kendall (AKA Brad Penn) When they came out with the first 20W/50 oil in 1972 we used it exclusively in our customers cars (now mostly Porsche) We still use it. Brad Penn as it is now called uses a superior paraffin based oil stock from northern Pennsylvania. This oil has plenty of the metals that insure long engine life. They also have a heavier metal oil specifically for break in. In vehicles that do not specify synthetic oils we uses this product exclusively. I do not believe that our shop has ever had a Brad Penn oil related engine situation. You are welcome to look at our web site WWW.AllZim.com for a review of their products. al zim
  • 20
    paul grant Seattle August 15, 2013 at 11:32
    Great article - thanks
  • 21
    bob bayarea August 15, 2013 at 11:55
    So..... what is the best oil for my 1961 356 porsche. I drive it 1000 miles or less per year. thanks ...bob
  • 22
    Jeff Dean Tucson, AZ August 15, 2013 at 12:00
    I use Valvoline VR-1 racing oil, 40W single weight, in my vintage BMW motorcycles. Plenty of ZDDP. Available at any NAPA.
  • 23
    Robert Atl. August 15, 2013 at 12:34
    Hi....... A lot of modern cars today have overhead cams which use shims. The shims are between the cam lobes and the top of the valves via buckets that hold the shims. No roller lifters used to open the valves with this set up. GM, Ford, Chrysler, Kia, Hyundai, Toyota, Nissan, Porsche, Ferrari ...etc use shims on most of their overhead cam engines . Other words, shims work like a flat tappet lifter (direct contact with the cam) and use the modern SN rated oil with less Zinc everyday. The modern SN rated oil uses other anti-wear additives (Boron) to replace the Zinc in the oil. Also, the API still use the same wear test to qualify the motor oil for our engines meaning if it fails the metal to metal contact it doesn't pass. So it's safe to use, "Todays Modern Day SN rated oil" in our older cars....
  • 24
    Steve Hamilton, ON August 15, 2013 at 12:49
    There is an article that disputes this one. (Wish I could find it). It basically says that ZPPD did play a part in motor oil many years ago, but tests now how shown that any good oil works perfectly well with the old motors with no scuffing of cam lobes or lifters being apparent. I believe the testing was done by GM, but don't quote me on that. I still like to use the Brad Penn Green Oil in my 1969 Buick GS 400. Never had any issues. I guess it's up to the individual....
  • 25
    db W.MI. August 16, 2013 at 01:20
    "So it's safe to use, "Todays Modern Day SN rated oil" in our older cars...." I strongly disagree with this statement, It has been proven many times that modern oil w/o the high levels of ZDDP, will in fact cause significant damage to vintage engines that are in our classics, particularly the camshafts in flat tappet applications.
  • 26
    Dave Quinn Michigan August 16, 2013 at 02:55
    I recommend Brad Penn for a break-in oil on new rebuilt engine due to it’s liberal dose of ZDDP, the best engine wear protection additive. After it’s broken in I recommend Valvoline Racing VR1 oil 20w50. 75% higher zinc than SM engine oil with a balanced additive package designed for both racing and street-legal applications. Protects older style push-rod and flat tappet engines. See this link: http://www.valvoline.com/faqs/motor-oil/racing-oil/ As was mentioned earlier Valvoline Racing VR1 is readily available at almost all auto stores. Richard, this is perfect for all your MG’s.
  • 27
    Dave Quinn Michigan August 16, 2013 at 03:08
    I recommend Brad Penn for break-in oil after an engine rebuild. And for everyday use Valvoline Racing VR1. As mentioned it is readily available at almost all auto stores. 75% higher zinc than SM engine oil with a balanced additive package designed for both racing and street-legal applications. Protects older style push-rod and flat tappet engines. Check out this link: http://www.valvoline.com/faqs/motor-oil/racing-oil/ Richard this is a great 20w50 oil for your MGs, that’s what I use in mine.
  • 28
    dan ohio August 16, 2013 at 19:35
    A few years ago this very item appeared in our car club magazine. The author of the article recommended oils that carry the SL designation because that meant the oil has the proper zinc for older cars. At the time he recommended Rotella Shell oil , which had the SL designation; however, Ive noticed that Rotella 10w 30 no longer carries that designation. I have switched to Castrol 10w30, which still carries the SL, at least for now. You have to look on the back of the bottle for these designations. I hope this helps some pf my fellow car collectors, who did not even think about this problem.
  • 29
    Larry Pumphrey IN August 16, 2013 at 08:05
    I have been using Classic Car Motor Oil from the IN Region of the CCCA in my 1937 V-12 Packards since the inception of the oil. I drove one from Times Square in NYC to the Golden Gate in San Francisco in May. I drive these V-12's over 6000 miles each year. The Packard V-12 is a very expensive engine to rebuild and I wouldn't want to trust any other oil to protect it. I would recommend CCMO to anyone with an older engine. The oil is very reasonably priced as the club has no overhead with an all volunteer member participation.
  • 30
    JOE DYER, IN August 16, 2013 at 21:05
  • 31
    Jerold Moore Florida, USA August 16, 2013 at 10:23
  • 32
    wayne Aiken sc August 16, 2013 at 10:27
    I bought a 1966 289 Mustang in 1966 & still drive it. It has 255,000 miles & was overhauled in 80's. is there a special oil for that engine. I don't have a problem with it & change it every 1500 miles or 2-3 months, I have been using good grade 10w30.. Any thoughts
  • 33
    Cal King AZ YYC August 16, 2013 at 11:10
    "Lucas Oil Engine Break-In Oil Additive - TB Zinc Plus" plus Mobile 1 has been in my oil changes lately. 454, blown 350 etc all seem to like the Mobile 1 and I feel better putting in $10 bucks of prevention. So far so good, I really don't work these engines very hard like the rollerized race engines.
  • 34
    Jan M Bernas Tonawanda, NY August 16, 2013 at 00:04
    I use a 15W-40 diesel engine oil in my cars. As I understand, you won't have a problem with modern oils - as long as you're running a stock cam and stock valve springs.. Problems come in when you're running a radical cam with super stiff valve springs. If you have a stock cam and springs, keep the oil clean and don't worry about it.
  • 35
    Frank Wichita August 16, 2013 at 00:23
    I have also used Valvoline VR-1 for many years available at any O'Reilly's. It is about a $1.00 per quart cheaper after you add in the shipping costs. Besides O'Reilly's have a strong car community sponsorship in the Wichita area, and many other parts of the country as well. Let's stick with the good guys at O'Reilly's
  • 36
    Edward Wesson United States August 16, 2013 at 12:50
    I have had four classic MG's , all with solid lifters, and my preference has always been Kendall GT-1, 20w50....Based on this thread, i wonder if it is now Brad Penn oil, or sold as a separate brand, with the same characteristics.? Until VR-1 Racing oil came out, the GT-1 had the highest ZDDP rating of all motor oils.
  • 37
    Bradley Nashville, TN. August 17, 2013 at 08:05
    I used to use Shell Rotella-T when I discovered the "oil problem". That was a good option. Now in one of my 69 Cougar 351W engines I use a regular 10W-30 with a small container of ZDDP additive that I bought a few years ago. I have about 7 left with one per oil change. Seems to work fine. In my other daily driver 69 Cougar I have started to use exclusively Royal Purple oil and filters. More expensive but all the reports, research, and testimonials have been so good that I had to give it a try. Only time will tell. I will report back my findings in 10 years on the Royal Purple HP oil.
  • 38
    Dennia CT August 18, 2013 at 04:28
    I put Mobil1 10W30W in my '58 Corvette 283 that has not been rebuilt (to my knowledge) and it seems to work well. So I tried it in my '71 Elcamino 454 that has been rebuilt and it leaked out everywhere, front and rear, went back to reg oil, but it still leaks a little from the front now, did not leak before trying Mobil1. Should I try an additive to stop leak or just keep drip pan under it and a quart of oil behind the seat when I take it out, as I do now?
  • 39
    swheaton NY August 18, 2013 at 00:48
    I have 42+ yrs exp wrenching cars/muscle cars etc including dealing with many flat tappet cam replacements and or performance upgrades over the yrs too. I also spent a lot of time researching the zddp issue associated with todays oils vs the zddp requirements for old school FT cam'd muscle car motors for an online muscle car community that was having issues with a significant increase in ft cam lifter failures back in the 2005-2006 timeframe. That included me sending oils out to a certified test facility (Black Stone) to have the zddp & detergent levels checked in many oils from diff mfgs along with also contacting oil engineers and chemists at oil mfgs & at ZDDPLUS & Camshiled etc to get zddp levels in thier product along with thier general take on what proper zddp lvl was for old school ft cam'd motors in muscle & classic cars. I also contacted engineers at crane & Comp cams asking same basic queation about thier thoughts/view on zddp lvl required for Ft cam apps vs todays oils with low zddp lvl.. So i will share some of the more important fatcs from all the work i did. I would like to 1st say using thre zddp additives like cam shiled zddp plus were a good stopgap for protecting ft cams some yrs back when there werent many oils on the market with proper zddp lvl for safe ft cam operation let along when running afteramrket perf cams with hihger spring rates. But its not a good idea at all to continue using those additive today when there are more oils produced today with proper zddp lvl for ft cam operation. If you dont get the mix ratio just right with using products like ZDDPlus etc you can actually upset the delicate ballance of the chemical additive pkg in the oil which in some cases can significantly reduce the zddp's effectiveness making your Ft cam'd motor much more prone to premature cam/lifter wear possibly leading to ft cam/lifter failure. So use oils readily avail with proper zddp for ft fam use ,i will list some oils avail today that you can use. Also,as for diesel oil like for ex 15w-40 std dino ,as of 1/2007 most of them had zddp in the 1300-1400ppm zddp is good for most aftermarket perf lvl FT cams,1500-1800 zddp with cover anything thru real hot aggressive perf ft cams.But too high of zddp lvl used for longer term other then breakin can possibly lead to increases corrossion so keep that in mind esp when using a ZDDP oil additive. Heres a list of some the oils avail today properly formulated for perf ft cam use/apps. Valvoline VR1 Race Oil avail in std dino and full syn has 1400ppm zddp,Castrol Edge 5w-50 syn 1300ppm zddp,Kendal GT Platinum 20w-50 1200ppm zddp,Chevron Delo std dino 15w-40 1300ppm zddp,sheel rotella 5w-40 syn diesel oil 1300ppm zddp,Spectro Golden Motorguard series oil avail in mult grades in std dino-smei blend-full syn all @ 1800ppm zddp,Classic Car Motor Oil (1500ppm zddp?),Motor Head Hi Z std dino 15w-40 1500zddp on avg,Joe Gibbs Hot Rod oil 1200ppm zddp,Cam2 HI PERF OIL in semi blend 2000ppm zddp,Hemmings motors news oil they advertise having increases zddp lvl required for FT motors (zddp lvl?) ,Mobil-1 Nascar approved 15w-50 syn 1300ppm zddp,Brad Penn Grade-1 oil formulated for FT cam apps-1500ppm zddp on avg,Amsoil & RP also mfg hi perf oil with increased zddp required for perf FT cam apps but ensure your getting those oils with increased zddp lvl because they mfg hi perf oil in both hi & low zddp lvl and you dont want to choose/buy wrong oil with low zddp for a hi perf Ft cam app.Hope this helped set the record straight on zddp lvls in oils currently on the market today along with zddp requirements for diff perf lvl ft cams too. But in general the majority of oils mfg'd today that arent the oils i listed above only have approx 800ppm zddp on avg,a few have 1000-1100ppm zddp but thats still not enough zddp to safely/properly protect a perf ft cam app. So with that said to be safe dont use oil your not sure of zddp lvl in a ft cam app,esp an aftermarket perf app.
  • 40
    Dave Michigan August 19, 2013 at 01:39
    Oil is not Oil. Anyone remember Quaker State Oil? How many engines lives were significantly reduced. So where does all of these comments leave us? No where. Opinions only, in my opinion. How about some facts along with references. How much ZDDP is in each quart as example? How much detergent is put into a oil? What type of oil is it? Now this would be an article worth reading!!! Assuming that supplied references would establish some credability.
  • 41
    J. Sass Sterling Heights, Mi August 19, 2013 at 16:01
    I lost 2 lobs on my Cam and 2 lifters (one almost half gone from wear) on my '67 Pontiac Firebird. The last owner used regular oil and I did not know that nor that zinc was taken out of the new oil for roller lifters. I had a great place to repair this as I wanted the car on the road quickly (I was not sure of the issue at the time) and they told me how they had some work return to them due to cam shaft wear outs which they fixed for free but then they also learned about the zinc needed for classic cars- they tell all their customers now (including me!) so that their customers do not lose an engine due to not enough zinc of all things.
  • 42
    swheaton ny August 19, 2013 at 11:38
    Dave,1st i just want to say sorry for this and my inital post being so busy/tight becuase this editor wont let me space anything out anwhere so it looks to be 1 continuous run on pragraph. Ok,mpving on, you ask how much zddp is in each qt oil with reff to back it up too. Well i just gave you that data i obtained from oil i had tested at a certified test facility or the oil mfg themselves which were the same oils i listed at the end of my inital post that included zddp lvls as ok to run with ft cam apps,if you dont belive that info comming from a certified test facility or from the oil mfg then your on your own. If you bother to take the many days/hrs i did doing all the research/work you could verify the zddp data i posted by paying to get the oils tested or by contacting mult oil mfgs to get the zddp data for thier oils to see it match what i posted here. And for the general public i see posting here oil is oil like it doesnt matter for Ft camd motors your incorrect/misinformed ,end of story. If you dont belive it go online to read what the people/engineers in biz have to say about it like for example comp cams/crane cams/Amsoil etc on the subject of using todays oils (Esp newest SN rated oil) with >50% less zddp in an old school FT cam app. And as for knowing what deteregtn lvls are etc in the oil,when the oil mfgs formulate the oil for FT cam apps they know what correct deteregnt to zddp lvl is to avoid issues so its not really a # we need to concern ourselves with when using oil properly formulated for ft cam apps as recieved from oil mfg. But guys using zddp additives like zddplus/cam shiled etc its tricky to ensure your dosing properly as to not upset the proper chem balance of the oils additive pkg wich when overdose with additves and significantly reduce the zddps affectiveness/ability to proptect a ft cam/lifters & is why dont rec using those additives other then in an emergency where proper oil for Ft cam apps isnt avail. This isnt rocket science at all,keep it simple by using oil properly fromulated by the oil mfg for FT cam apps and forget about it,its that simple! (That also includes using a proper quality assmebly lube like cranes grey mly type paste along with breakin oil or additive for breaking in a FT cam like cranes Superlube breakin additive both avail from summit ) Thats why listed oils ok for Ft cam use to help you guys out running ft cam apps. I spent mult yrs & countless hrs researching this issue directly talking to oil & chemical engineers @ oil mfgs and also talking to engineers/owners of zddp additive mfgs like ZPPLUS & Cam Shiled along with engineers/techs @ Comp cams too with the oil testing i had done & my own 42+ yrs 1st hand exp wrenching old school FTcam'd motors too. You can either verify what have said thru spedning time & money doing oil testing of your own and contacting oil & chem engineers at oil mfgs & engineers at Ft cam mfgs like comp cams to see for yourself whats going on or simply choose to belive it or not,thats up to you. I am just trying to freely pass along the results of my yrs researching this issue onto the guys here running Ft cam'd motors . And i can assure i am not just a copy paste intranet junky looking for glory,i truely do have 42+ yrs with ft cam'd motors and did spent mult yrs researching the zddp issues with todays oils vs proper oil for FT cam use. If you post you your email address here i would be happy to send you a file i have on what the oil mfgs and Ft cam mfgs had to say about running todays oil with low zddp on old school FT apps. Happy motoring!
  • 43
    swheaton ny August 19, 2013 at 11:54
    DENNIA,a few reaqsons syn oil sometimes leaks in older gen motors is because on a mollecular lvl the molecules in syn oil are smaller along with it being slicker/more slippery making it easier to get past gaskets & seals on the older gen motors too.Todays motors have much more ridged cast AL oil pans valve covers with wider sealign surfaces along with better gasket seal tech too that collectively seals much better then old gen motors do with stamped steel paarts with thinner sealing surfaces etc. OK,on the M1 10-30 in your 58 vette with sbc & FT cam if motors stovk motor,dont use that oil in that because it too little zddp which could over time lead to premature cam/lifter failure. So i'd rec swithcing to one of the oils i rec in my inital post here that are properly formulated for old school FT cam apps. Same goes for your bbc if its got a Ft cam. But if your bbc is a roller setup it can still benefit from oil fortified with more zddp so you could still use that oil in it too. And switch back to std dino oil in your bbc which should reduce the oil leakage you said started with the syn oil.Since your bbc has been rblt take a few mins to chk bolts on oil pan/valve covers/timing cover/intake etc to ensuer they are snug,dont over tighten either,just ensure they are snug.
  • 44
    Paul Dayton, OH August 19, 2013 at 12:40
    I currently use "Motorhead Hi Z Classic Motor oil" - you can get it on-line or on e-Bay (no I'm not a rep of theirs) - my 1968 390GT engine started developing a rod knock which turned out being a bad crank/rod bearing from semi-syn oil I was using at the time (2003 -) - they had less than 1000 mi on them - most of them still had the coating on 'em - 3 yrs ago, I tore it apart, had "Ohio George" Montgomery rebuild my short block, turn the crank & rebuild the heads - he told me not enough Zinc in my oil caused most of my problems (also whomever had rebuilt it previously) - about 10+ yrs ago I hadn't heard anything about "old" engines needing ZINC - I will never run any engine on new oils again!
  • 45
    swheaton ny August 21, 2013 at 02:14
    I caught onto to the issue with low zddp/zinc & Phos i most oils sold over counter back in approx 2005 when guys running FT cam lifter motors in the large 70k member online forum i belong to were experiencing very high ft cam/lifter failures that i decided to investigate. Thats when i found the oil mfgs had significantly reduced the zddp lvls in most oils sold over the counter from approx 1300-1500ppm zddp to approx 800ppm on avg but a few still have 1000-1100ppm zddp which is still on low side for safe ft cam operation even for low perf stock apps with less agressive lobe design and mild spring rates. The reason the zddp was reduced was the EPA/Gov agencies mandated the oils mfgs reduce zddp in thier oils due to it sometimes fouling cat converters in higher mileage cars rendering them inaffective causing emmissions issues and warrantee issues too. And on top of that the motors mfg'd today either have roller cam setups that arent quite as sensitive to lower zddp lvls or have OHC setups running much lighter spring rates due to that design valvetrain having no pushrods -rocker arms-heavy valves to keep in control from floating at higher rpms so the oil mfgs thought it wasnt an issue to reduce the zddp in most oils. Well the big problem with all this was the fact the oil mfgs never publisized the fact they significantly reduced the zddp lvls in many over the counter oils and thats where guys with classic cars running old school F cam/lifter setups (esp aftermarket perf FT cams) got into trouble. Another thing to realize is that if a classic car with Ft cam motor has had the improper oil with low zddp in the motor for enough miles there could possibly ( but not always) be enough premature wear & damage already done to the FT cam/lifters that if they switch to oil with higher proper zddp that it will not fix the problem ,it may slightly extend time before the cam/lifters fail but it will more then likely result in an inevitable cam/lifter failure down the road someday . But if you were to run low zddp oil in a low perf FT cam motor with a bone stock FT cam with non agressive lobe design and lower spring rates where motor doesnt see much idling time in traffic with the motor idling low in gear with much lower oil pressure (= less oiling from lifter bores) and less oil slung from crank at low idle rpm for less oiling of cam lobes from below thats where you may very well get away with running low zddp oil in a low perf FT cam app. But with all the oils avail today with proper zddp lvl as i posted in my inital post here) theres no reason to chance it or to take chance of overdosing a low zddp oil with a zddp oil additive possibly impeading the zddp ability to protect the FT cam /lifters. Happy motoring!
  • 46
    Sam Nicolosi Dayton, Ohio August 21, 2013 at 19:57
    Thank you, "Paul from Dayton, Ohio" for the kind words that you shared about MotorHead "Hi-Z" Classic Motor Oil ! (I have to reveal at this point that I DO represent MotorHead Oil and Hi-Z additives. In fact, it's my company... and yes, I am also a Haggerty client... because I love old cars too). I would like to take this opportunity to inform (anyone who is interested) that our additive package (ZBoost) is a VERY economical way to "get your daily dose of Zinc"). Our products are easily found, both on eBay and at our website (MotorHeadOil. com)... keep those motors humming!
  • 47
    Doug C Derry, NH October 27, 2013 at 08:11
    I use Valvoline ZR-1 10W30 Racing Oil in my 67 Firebird. This does contain ZDDP, works well, and readily available at about $6.00 per quart. Other weights are available as well.
  • 48
    Mel W Nebraska March 9, 2014 at 19:01
    Just found this discussion and since I have been worried about what oil to run in my 65 mustang with a stock 200 c.i. and my 80 gmc pickup wit a stock 350 engine for some time now, I have been using old stock sl rated oil, and no problems so far. Of course neither gets driven hard or very many miles per year. What is the experts opinion on the Quaker State Defy oil, that says it is for older cars and says it has much more (up to 50% more) zddp than regular sn oil.
  • 49
    C J Calabasas, CA February 15, 2015 at 12:12
    I'm just wanting to read the comments but it's making me post a comment.
  • 50
    Ron McDonald Saskatchewan September 1, 2015 at 11:08
    Joining oil discussion
  • 51
    Corvette Hex Anaheim , California September 10, 2015 at 12:15
    i use Vintage Car Motor Oil - from Surf City Garage in Huntington Beach, California (no i'm not a rep) it has high zinc- i think it says 2000 ppm of zinc - my cars run good on it, no problems - cars runs smoother - i have a few older corvettes. My brother told me about it and he runs it in his 57' chevy too.
  • 52
    Charles Beeker Bloomington IN September 16, 2015 at 07:43
    Enjoyed this detailed discussion as I am concerned about proper oil for my vintage CJ2As and my classic 1964 GMC Truck. Now that I know the Indiana Region of Classic Car Club is in this mix, I plan to support them with their recommended blend.
  • 53
    Rizzo New Jersey January 20, 2016 at 19:01
    I have a 1967 chevelle with a 396, what oil do you recommend dino or synthetic and what brand oil filter? Thanks
  • 54
    Laurie Mallorca, Spain July 12, 2016 at 07:07
    Zddp is critical when breaking in a new engine with a FT cam , It sgould be above 1200 , but after the engine is worn in 800 to 1000ppm is fine for most engines unless you have a wild cam in it, Valvoline Vr1 20w50 non synthetic is probably the best conventional 20w50 on sale , with 1300ppm

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