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ZDDP oil additive

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AUSMHLY

AUSMHLY

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I've searched the archives about ZDDP. Seems we need to add it to the Castrol 20w-50w engine oil.

Anyone recommend any particular brand of ZDDP additive?
Here's what a quick search came up with:
(Note the last brand, ZDDP-MAXX says their's is more concentrated than brand ZDDPlus. Marketing?)

https://www.cam-shield.com/acatalog/Cam-Shield_Oil_Treatment.html

https://www.eastwood.com/ew-zddp-oil-additive-4-oz.html

https://www.zddplus.com/

https://www.ebay.com/itm/1-ZDDP-MAXX-ENGI...bf#ht_859wt_953
MORE CONCENTATED AND COST LESS THAN ZDDPLUS. ZDDP MAXX TREATS 5 QUARTS OF SM OIL AT OVER 1800 PPM PHOPHORUS AND 2500 PPM ZINC.
 
Roger, I just received five 4oz containers of ZDDPlus for $42 including shipping and no tax. I've used this brand before. You will go crazy trying to figure which is best. The point is, any zinc additive is better that what we get in today's oil. I add one once a year when I change the oil which I just did before putting her away for the winter (if it ever does come up here - zero snow so far. I may have to take her out again.)
 
Richard,
That brings up another question.
Is 4 oz enough for the Healey? The inline six requires 6-7 quarts of oil.

ZDDPlus says:
Place a 4 ounce bottle of ZDDPlus™ into a typical 5 quart (160 ounce) oil tank.

Would you share with us a link to where you got them?
 
Again, better than none. What would one do when adding oil to top up as needed? Many don't feel the need to use ZDDP accept for initial "brake-in" period after rebuild.
 
It really is best to start with an oil that has all the additives already included! You can do harm by playing with oil add's. Use Valvoline VR1, Shell Rotella, or any of the major HDEO 15w40's, Brad Penn, etc, etc. There are many oils that already contain the right stuff. Plenty of info on Bobistheoilguy.com
 
oliver88 said:
It really is best to start with an oil that has all the additives already included! You can do harm by playing with oil add's. Use Valvoline VR1, Shell Rotella, or any of the major HDEO 15w40's, Brad Penn, etc, etc. There are many oils that already contain the right stuff. Plenty of info on Bobistheoilguy.com
Click to expand...

oliver88,

Sure that would be nice, but the oil that most people recommend/use here is Castrol 20-50. I've been very happy with it over the years and have stockpiled enough for a couple more oil changes, when it went on sale. This is why I'm asking others who use Castrol 20-50 what ZDDP brand additive they use. Tahoe healey uses ZDDPlus, seems to get a good deal on it, but keeps his source close to his chest :whistle:
 
This company offers various grades of ZDDP enhanced oil.
Classic Motor Oil

I am a bit dubious about the fuss about reduced ZDDP levels hurting older cars with flat tappet engines -- especially since many modern cars still have flat tappets and probably higher valve spring pressures than our old Healeys. Reminds me of the unleaded gas fears that have been exaggerated for years.

But it may be best to take care and use the enhanced oils that are out there.....
 
Try ebay. There is a page of it there. Look for ones with free shipping and out of state (no tax) and then the best price. No secret. I received my order in three days.When I cannot find something, my wife finds it for me. She just found me a source for yellow fog light bulbs for my Lucas fog lamps that I have been looking for for a year. (I bought 4 since they are no longer made. They say when they are gone, they are gone.) Resourceful. You want the best price for something, ask her.
 
oliver88 said:
It really is best to start with an oil that has all the additives already included! You can do harm by playing with oil add's. Use Valvoline VR1, Shell Rotella, or any of the major HDEO 15w40's, Brad Penn, etc, etc. There are many oils that already contain the right stuff. Plenty of info on Bobistheoilguy.com
Click to expand...

:iagree:

Use racing oil such as Valvoline VR1. These oils were not altered to meet modern engine specifications and include the required ZDDP.--Fwiw--Keoke
 
I know that talk about which motor oil to use is like talking
about religion but I will take the risk....

Castrol syntech 20w-50 for classsic cars is no longer being made.

They came out with Castrol Edge with syntech technology and labeled that " for classic cars ". I think the viscosity was
changed but I don't remember the new viscosity the high number
was -50. I have seen it at pep boys for over $8. a qt.
...
Walmart sells Mobil 1 15w-50 in both the 5 quart containers as
well as the qts for a lot less than $ 8.00 / qt.

Mobil 1 15w-50 does contain ZDDP and is made for racing and
cars with older valve train components that require wear protection. Here is a link to their data sheet and you will see the zinc and phosphorus contents are listed.

https://www.mobiloil.com/USA-English/MotorOil/Files/Mobil_1_Product_Guide.pdf

I just look for either the mobil 1 15w-50 or the Castrol edge
xxw-50 for classic cars , which ever is on sale. I also add one container of STP that also contains ZDDP .

The STP is probably not necessary but since it is cheap, I add one with an oil change in the Healey.

.... Your opinion may vary ....

Ed
 
John,

Yes, that is the oil I was talking about. It has enough ZDDP in it for our cars, just like the Syntech 20w-50 had.

Tahoe and Roger,

I think you guys are still using the regular dino Castrol 20w-50 which is a fine oil but they don't say how much, if any , ZDDP it contains thus is the reason I switched to Syntech Castrol that did contain the ZDDP. Castrol did stop making the syntech 20w-50 but replaced it with Edge 5w-50 which also contains ZDDP. The Mobil 1 15w-50 also contains ZDDP and is made for older cars.

If you want to use dino Castrol 20w-50 then add one or two containers of STP which is the cheapest product I found that contains ZDDP and is available at Walmart .

Ed
 
Isn't 5w a bit light unless you are in real cold climate? When you have cars as valuable as Healeys, an extra few bucks per year is nothing. I have always used Castrol 20w-50 in my British cars and have never had problems. I've been adding ZDDP for 6 or 7 years changing oil every year (aprox 3k/yr). I would feel different it I was racing or driving in stop and go commute or if I didn't change the oil as often. There is not one answer for everyone. That's why they make different flavors of ice cream. But I do feel the ZDDP is important for our flat tappets no mater how you get it.
 
Honestly guys...you really need to be careful with this stuff...You can sludge up the engine quickly or worse..adding too much ZDDP will corrode and pit camshafts, etc...Stay away from Lucas and the blue bottle STP...if you insist on an add I know the Redline Break In additive is well formulated. Follow the directions on the bottle if you use it. It really is best and safer to start with a high quality oil...There are many available.
 
The 'knock' on 10W-40 oil--supposedly, some car manufacturers would void your warranty if you used it--was that the cold/hot viscosity spread was too great and the viscosity improvers would break down. I doubt the viscosity index is linear, but 5W-50 is a greater spread than 10W-40 (obviously). That means the base oil stock is probably around 2-3W, with a lot of VIs added. The VIs break down due to shearing forces, meaning your oil loses viscosity over its lifespan. Maybe the formulations have improved, but I'd have at least some concern using an oil with such a high viscosity spread (I know some pure synthetics like Mobil 1 have high viscosity spreads, but I'm willing to give a pure synthetic <some> benefit of the doubt).

Disclaimer: my father has used 10W-40 in all his engines--cars, trucks, tractors, fire engine, orchard sprayers--for years, and none of his engines have had ill effects.
 
I run the TC Europa on Castrol Syntec (now Edge) with ZDDP included, and no additives.
The recently re-built Elan engine though has Castrol GTX 20/50 with added ZDDPlus and will do so until fully broken-in when it will make the switchover to synthetic.
That's what makes me feel I'm protesting my engines as best as I can.

P.S. The Elise gets Edge 5/40. I've always been a Castrol guy - I used to run my racing Austin Sevens on "R".
 
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