View Full Version : oil

02-03-2007, 05:40 PM
I was talking to a friend of mine and he was telling me about that the new oils have reduced [ZDDP] zincdithiophosphate.He said that some older cars are having problems with their camshaft because of this.. Has anybody heard anthing about this?


Ed Rivkin
02-03-2007, 05:47 PM
Yes. It has been discussed many times before in the forum. You want an SJ oil; not SL oil.

One of the threads where it is discussed.


02-03-2007, 07:22 PM
Sal .... It is very true. It is caused by the EPA mandating the reduction of zinc in oils to extend the life of catalytic converters.

The solution is to use a diesel oil that has no need to reduce these additives (no catalytic converter). My recommendation is Castrol GTX Diesel 15-40W. It has the only oil data sheet that I have found that contains zinc and phosphorus.
Data Sheet (http://www.castrol.com/liveassets/bp_internet/castrol/castrol_usa/STAGING/local_assets/downloads/p,q/pds_GTX_Diesel.pdf)

02-04-2007, 02:23 PM
Fritz's recommendation was to use the oils that were used when the car left the factory. If they ran good at that time they should run as good now. Therefore, I always used Quaker State 30 Wt. It now appears that I need to check to see if the QS 30 wt. is an SL or SJ oil. And just when I was comfortable with my oil selection.:(

Ed Rivkin
02-04-2007, 02:33 PM
Absolutely check because the valve train is at risk. It's just one of our many challenges....

BTW, the car is looking good.

02-04-2007, 04:11 PM
Quaker state is NOT on the approved list. Castrol, Shell and a few others are.

If worse ever comes to worse, I will go with Castrol Classic. They still make the approved XL version. Expensive!

Or go use diesel oil, which I may investigate next.....

Ed Rivkin
02-04-2007, 11:11 PM
Castrol GTX available at Wally-Mart is an SJ oil. Jim, are you using the Diesel version to get the zinc and phosphorus in the oil. I'm curious how important/desireable/critical those additives are.

I would appreciate your insight and perspective. Perhaps this will be part of the discussion/education next weekend for us dummies.

02-05-2007, 08:24 AM
Ed ... ZDDP will be very central to my presentation at WinterTech. There will also be an article forthcoming in the Newsletter on oils that is a reprint from another magazine on the author's inquiries into the capabilities of modern automotive oils.

Everything appears "hazy"; it is very difficult to find any facts about the additives and capabilities of automotive oils. There are trade-offs between oil additives and government regulations to extend the life of catalytic converters and I don't want to trade any long term engine protection. It appears that "SL" oils "should" provide adequate protection but I just don't know and can't find anything that convinces me. Mobil 1 10W-30 is SM, SL/CF and other certifications but is "Energy Conserving". Mobil 1 15W-50 is SM/CF (not SL) and not "Energy Conserving". The data sheets on these oils do not show any zinc or phosphorus. I have been a believer in Mobil 1 for years but now I am not sure.

GTX Diesel oil 15W-40 is CF/SL and SJ and not "Energy Conserving" but more important to me, it has a percentage of zinc and phosphorus in its data sheet.

I have heard enough from enough sources to believe that there is a real issue with "Energy Conserving" oils and old engines. With the uncertainty, I just make the most conservative choice.

02-06-2007, 10:15 AM
I use Castrol Classic XL20w/50. The spec is shown as API service SE/CC. Beware modern oils designed for the tighter tolerances on modern engines: they do not like to stay inside old engines and will weep past the nearest seal they can find!
See for full details.

02-06-2007, 02:22 PM
Rod .... Castrol Classic is exactly what I want. I have not been able to locate it locally. Perhaps it our envirmental regulations prevent its sale in the US.

Has anyone seen this oil in the US?

Jim Morris
02-06-2007, 09:22 PM
To quote Dema Elgin (see earlier thread referenced as a link above where I describe who he is), in a section dealing with "Flat-tappet Cam Lubrication" (doesn't apply directly to our set-ups because we don't have lifters):
"The pressure between the cam and lifter can reach 200,000 psi. Oil is squeezed out. Zinc dioxide dithiophosphate (Lubrizol ZDP) anti-scuff oil additive plates the surface under pressure, chemically combines with the iron as iron phosphate, then wears off one layer of atoms at a time. The zinc becomes chemically active at 600F, after engine comes up to temp. Most cam wear happens at start-up and at low RPM from lack of splash lubrication. Do not let a cold engine idle. Run 1500 RPM when cold to keep the cam lubed." (Source: Dema Elgin (2002). High Performance Engine Theory. San Bruno, CA.: Faster Forge & Press. Page 48.) On the other hand, in a later section he warns against revving a cold engine (i.e., BEYOND 1500 RPM, up and down). In addition to the flat-tappet camshaft quote here, he told me in person that our overhead cam, rocker arm engines need this additive ESPECIALLY. He uses Chevron Delo 400, and therefore, so do I! If you can't find this oil at your Chevron/Standard Oil gas station or auto parts store, go to your local Chevron distributor who will sell it to you in the weight you want. I pass this on only as information, not as advice.

02-06-2007, 09:58 PM
Jim .... One more voice. Delo is: 'D'iesel 'E'ngine 'L'ubricating 'O'il.

I finally located a Chevron Delo 400 Data Sheet (https://www.cbest.chevron.com/msdsServer/controller?module=com.chevron.lubes.msds.bus.BusPD SList&alphabetSelected=D&alphabetSearch=Y&language=EN&country=&region=NA&isLoginPage=true%22) and this oil also contains Zinc and Phosporous.

This supports my general rule of thumb of choosing a deisel oil. It is a "SL" oil (not SM).

Jim Morris
02-06-2007, 10:51 PM
One more note while we're at it (again). I have been told on a couple of occasions that "...you shouldn't use diesel oil in gasolene engines because....". This is a myth, according to experts like Professor Elgin. There is nothing IN or nothing LACKING in oils like Delo 400 that makes these diesel oils incompatible with gas engines. Moreover, my own experience, from Porsche 356's, 911's, Mercedes 190SL, 250SE, 280SE 3.5, and more modern E320's indicate this oil works very well. On every one of these cars I have had to rebuild (after high mileage), the reason was always a burned valve, or non-lubrication related failure. Without exception, even with extremely high mileage (e.g. I put over 250,000 miles on the 356 Porsche, and 3 rebuilds), each rebuild revealed camshaft components and bottom end (crank and bearings) looking like new -- running always on Delo 400. I have been using it for 40 years. So......don't let some parts store clerk or mechanic tell you you shouldn't use "diesel oil" in your gas engine.

02-07-2007, 05:02 AM
Here is a good article (http://web.telia.com/~u42107551/oil.txt) with an interesting chart.

02-07-2007, 03:50 PM
Joakim ... An interesting article but I suspect that it is a little dated. It referees to the rating of "SG" which was for 1993 and older engines. He doesn't mention the current "Energy Conserving" problem.

Also, the current Castor GTX automotive oil marketed in the US does not contain Zinc.

02-08-2007, 12:37 PM
I contacted Castrol with this question and here's their answer:

Castrol is aware of articles in enthusiast magazines and web-sites, as well as after-market parts manufacturer discussions concerning GF-4 engine oils and cam-shaft durability issues in older performance vehicles. Some consumers suspect the lower level of ZDDP in GF-4 oils may be causing these failures. Castrol is currently investigating this issue.

As indicated on our product packaging, the current engine oil category API SM/ILSAC GF-4 is fully backwards compatible or 'back serviceable' and has been extensively tested. Valve train issues are not anticipated with the use of modern engine oil in older cars of OEM stock configuration. In fact, current SM/GF-4 engine oils are subjected to testing that is far more intensive than engine oils of previous API/ILSAC categories.

To clarify, in general, ZDDP levels have been reduced a small amount in the current category engine oils (API SM/ILSAC GF-4) in compliance with industry regulations that set maximum levels of Sulphur and Phosphorus, but are still at levels that provide ample engine protection.

Special procedures have always been recommended for the proper initial break-in of a new, matched, cam and lifter set; which include the use of a properly formulated cam break-in lubricant paste which typically contains a healthy dose of molybdenum. Engine oil alone is typically insufficient for break-in of a new cam and lifter set, particularly in a vintage engine type built to historic specifications.

For those consumers that wish not to use a GF-4 oil in these vehicles, Castrol does offer the following products that contain Zinc at a level that is higher than the Zinc level found in oils (API SG) marketed during the "muscle car" era of time:

* Castrol GTX 20W-50 (SL,SM)
* Castrol GTX Diesel 15W-40 (CI4,CH4,CG4,CF4,CF,SL)
* Castrol GTX High Mileage 20W-50 (SL,SM)
* Castrol HD 30 (SL,SM)
* Castrol HD 40 (SL,SM)
* Castrol Syntec Blend Truck 15W-40 (CI4,CH4,CG4,CF4,CF,SL)(Semi-synthetic)
* Castrol Tection Extra 15W-40 (CI4Plus, CI4,CH4,CG4,CF4,SL)
* Castrol Hypuron S 15W-40 (CI4Plus,CH4,CG4,SL)(Semi-synthetic)

The following Castrol products have Zinc levels that are typical of API SG
* Castrol Syntec 5W-40 (SL,CF)(Synthetic)
* Castrol GO! 10W-40 Motorcycle Oil (SG)
* Castrol GO! 20W-50 Motorcycle Oil (SG)
* Castrol Grand Prix 4-Stroke Motorcycle Oil 10W-40 (SG)
* Castrol Grand Prix 4-Stroke Motorcycle Oil 20W-50 (SG)
* Castrol TWS Motorsport 10W-60 (SJ)(Synthetic)

If installing a new performance cam in an older performance vehicle, it is important to:
* follow the installation recommendations provided by the cam manufacturer
* use the recommended cam break-in lube
* prime the engine oil circuits
* use the recommended engine oil
*confirm valvetrain geometries prior to starting the engine with the new cam


02-08-2007, 12:52 PM
I also emailed Exxon/Mobil and here's their answer:

You should utilize the Mobil1 15W50 which has high levels of
phos/zinc levels to protect your older valve train.

I still haven't heard back from Valvoline or Havoline. Stay tuned.


02-08-2007, 09:20 PM
The Castrol GTX Data Sheets (http://www.castrol.com/liveassets/bp_internet/castrol/castrol_usa/STAGING/local_assets/downloads/p,q/psd_gtx_usa.pdf) does not show ANY zinc.

Castrol GTX Deisel Data Sheet (http://www.castrol.com/liveassets/bp_internet/castrol/castrol_usa/STAGING/local_assets/downloads/p,q/pds_GTX_Diesel.pdf) show 0.13% zinc.

Castrol GTX High Mileage Data Sheet (http://www.castrol.com/liveassets/bp_internet/castrol/castrol_usa/STAGING/local_assets/downloads/p,q/pds_gtx_high_mileage_usa.pdf) does not show ANY zinc.

So, which oil is better for our old engines?

02-09-2007, 05:40 PM
Here's the reply from Havoline:

Thank you for your inquiry. Zinc has not been removed from gasoline engine oils, it has only been reduced. in place of it we now add molybdenum disulfide for antiwear. For older vehicles, I recommend the Delo 400 10W30. it is a diesel engine oil and it is loaded with zinc. I do not recommend this oil in any vehicle with a catalytic converter, but the cars you referenced would not have them. I have attached a product data sheet for your information.

Here's the PRODUCT DATA SHEET (http://home.pcmagic.net/bertfam/misc/delo.pdf).


02-12-2007, 03:25 PM
And the reply from Valvoline...

The consensus in the industry is that the current chemical limits of the GF-4/SM category are still sufficient to protect all "street" engines, including older flat tappet foller engines. The engine tests required for a GF-4/SM product is just as severe as the older, higher ZDDP allowed category. For the special applications (aggressive cams, high HP racing motors, etc) where the customer needs more ZDDP protection, our NON-GF-4 products still contain the higher levels (such as VR-1 and "not street legal" racing).

Still waiting for Pennzoil to reply...


03-26-2007, 01:21 PM
Another oil article which, amongst other things, shows where to get additives to replace the missing ZDDP we need.


12-15-2007, 08:34 PM
OK, I am at the point I have to jump. So far on this forum I see that the Delo 400 appears to be the way to go. However, there was a newsletter that came out on this subject recently & I've misplaced mine or lost it. So what is the latest thinking?

12-15-2007, 09:26 PM
Ron ... I use Castrol GTX Diesel 15-40. (http://www.castrol.com/liveassets/bp_internet/castrol/castrol_usa/STAGING/local_assets/downloads/p,q/pds_GTX_Diesel.pdf) The key additive is ZDDP which cannot be sold for a vechicle with a catytlic converter. There was an excellent discussion on the MBCA Forum on oils. (http://mbca.cartama.net/showthread.php?t=23688http://)

04-09-2008, 04:01 PM
I have just had a lot of work done including an oil change while it was in. Their recommendation was Valvoline 20w/50 Racing - 'better film retention and retains strong oil pressure when driven hard for long periods of time'.

04-09-2008, 06:18 PM
Rod .... In England, you have different oils, not affected by US regulations.

04-14-2008, 07:35 PM
Has anyone had experience with zinc containing, full synthetic, diesel oils on the 190 SL? I was looking at the Redline Full Synthetic Diesel oil. (specification sheet attached) I use Redline synthetic automobile oil in my other cars. Any problems with seal damage with synthetic oils on these old engines? Might synthetic provide as bit more protection?

Martin Chin

04-14-2008, 09:54 PM
Martin .... It has 0.12% ZDDP, excellent for protection. Synthetic oils tend to weep through seals. That causes no damage but a spot on the garage floor or a "protective" coating on the underside of the car.

04-14-2008, 10:11 PM
Martin .... It has 0.12% ZDDP, excellent for protection. Synthetic oils tend to weep through seals. That causes no damage but a spot on the garage floor or a "protective" coating on the underside of the car.

I don't see phosphorus or the TBN in that safety report. Yes, the .12% Z is excellent, but you'd like to know the other two numbers and what the detergents being used are.

Roger Worldie
04-14-2008, 11:52 PM
Great Gentlemen,

A more concise and informative dialog on the merits of oil in our engines could not have been more enlightening. I have been using Delo for some time now and was very pleased to see a consensus on the merits of the stuff.

BTW I am running molybdenum disulphide (MDS) at 2 to 3% by volume in the trans (using 90 weight gear oil, not auto trans fluid as recommended by the factory), differential and steering box for many years now and have yet to experience any problems.

After running the MDS in the engine and then tearing it down for a re-build one noticed that the interior cast iron areas of the block were coated with the MDS and in the pan there was an accumulation of the stuff as well, as it is heavier then oil and settles. Since that discovery I no longer add MDS to the engine oil.


Does any one have a perspective on the usage of MDS in engines?