zddp oil additive

Thanks James and Hard times. I'm glad I asked first. I was told to use it by a friend who said he heard that from someone else and to check into it first.
Rotella 15w 40, thats what I use in my diesel truck. I get it from Tractor supply.
Same stuff?
 
MrTube said:
It is my understanding no oil had zddp in it when the "A" was designed and the low spring pressure of the "A" does not require it.
Click to expand...
That's correct Mr Tube. ZDDP was designed for the higher spring pressures and flat tappets beginning in the 50;s. Today's engines normally have roller tappets or overhead cams and don't require it. Kind of leaves the motors it was designed for out in the cold. I lost 2 cams in 2 different small block chevys because of this. With the low spring rates of the Model A it is unnecessary. It won't hurt to use it, it's just an added expense for no good reason.
 
From Wikipedia:



The main use of ZDDP is in anti-wear additives to lubricants such as greases, gear oils, and motor oils, which contain about 1%. For applications in oils for gasoline engines, zinc and phosphorus emissions could damage catalytic converters and have had their quantity reduced in standard formulations.[3]. Reduced ZDDP oils have been cited as causing damage to, or failure of, classic/collector car camshafts and lifters with flat tappets which undergo very high boundary layer pressures and/or shear forces at their contact faces, and in other regions such as big-end/main bearings, and piston rings and pins. Some racing oils such as Valvoline ZR-1, and aftermarket additives, are available in the retail market with the necessary amount of ZDDP. See "external links" in this article. The same ZDDP compounds serve also as corrosion inhibitors and antioxidants.

Another article.
http://www.mustangmonthly.com/techarticles/mump_0907_zddp_zinc_additive_engine_oil/index.html
 
i use valvoline 20/50 RACING oil with ZDDP . for yrs now . i tried penzoil , but when i went back to the 20/50 my idle rpm came up 100 rpm ................ sold me
 
sidevalve said:
Thanks James and Hard times. I'm glad I asked first. I was told to use it by a friend who said he heard that from someone else and to check into it first.
Rotella 15w 40, thats what I use in my diesel truck. I get it from Tractor supply.
Same stuff?
Click to expand...

As was stated, in response to your original question...i.e.- if concerned(that your oil doesn't contain the additive) then use Rotella...which does contain it;)! Which is why truckers use it , I am told.
I don't give a hoot about this additive, in model A engines, but use Rotella: because of its various other good qualities! And, I figure, truckers use it because it preserves their diesel engines (which may be worked slightly harder than my B)...cost be damned:)...after all the thousands put into building an engine to run like a 'singer', to fret over cost of four qts of oil!
 
hardtimes said:
As was stated, in response to your original question...i.e.- if concerned(that your oil doesn't contain the additive) then use Rotella...which does contain it;)! Which is why truckers use it , I am told.
I don't give a hoot about this additive, in model A engines, but use Rotella: because of its various other good qualities! And, I figure, truckers use it because it preserves their diesel engines (which may be worked slightly harder than my B)...cost be damned:)...after all the thousands put into building an engine to run like a 'singer', to fret over cost of four qts of oil!
Click to expand...
I like your attitude!:D
 
I was told to use it in our new rebuilt engine...the builder has been around for many years and has rebuilt a lot of model a engines!
 
James Rogers said:
That's correct Mr Tube. ZDDP was designed for the higher spring pressures and flat tappets beginning in the 50;s. Today's engines normally have roller tappets or overhead cams and don't require it. Kind of leaves the motors it was designed for out in the cold. I lost 2 cams in 2 different small block chevys because of this. With the low spring rates of the Model A it is unnecessary. It won't hurt to use it, it's just an added expense for no good reason.
Click to expand...

I had a big concern with this before I traded in my 92 chevy truck that had a TBI 350 in it a year and half ago. I had mixed answers from people. Some claimed the 4 bolt main 350 that was in the 8600lb GV trucks had a roller cam. Most claimed it was flat tappet. Either way by 226,000 miles zddp or not I'm sure the cam was pretty worn.

I think this was also why I felt the power drop off around 3500rpm rather then the original redline of 4500. I always found my self shifting at 3500 if I wasn't watching the tach. If I tried to wind it out past 3500 the power dropped off bad near 4K. Exhaust was newish with a honey comb type stainless 3" cat so the exhaust wasn't plugged.

Oddly enough I swear the engine was strong and could run right to 4500rpm until around 210,000 miles. It seemed like it was a steep down hill from there. :(
 
James,
I agree that the A has low spring pressure. The last 2 cams I installed were for flat-
head V/8s, an Isky and Schiender, both recommended zddp or some form of high
zink.
Dudley
 
That comment Jeff quoted from the Jasper Engines guy about ring spacing is pure baloney! Rings rotate at random in their grooves so do not stay where you install them anyway. Besides, is oil only smart enough to go straight up and out when/if the ring gaps are lined up? I think not! Any oil that gets above the oil ring will accumulate until it fills the space between the 2nd compression ring and oill ring, then squeeze through the 2nd ring gap no matter where the gap is and then on to the top ring and through the gap no matter where it is. Many other reasons to burn oil: Manufacturers use low tension oil rings to reduce friction and increase gas mileage (by a fraction of a MPG). Maybe Chevy got them too weak. Or too little clearance in the ring groove, preventing full ring contact with the cylinder wall. Gummed up rings from oil and gas deposits (a big problem back in the '60's). Vacuum leak in the intake manifold or gasket sucking oil into the intake ports. Restricted PCV valve, causing crankcase pressure to build up and push oil out. Sticking fuel injectors letting gas into the crancase, diluting the already thin (5W-20) oil.
 
Rotella has had its level of ZDDP reduced so much in the last couple of years that ZDDP is not the reason to be using Rotella. You may want it for other reasons, I wouldn't touch it. Diesel engines have totally different requirements, and there is an additive missing from Rotella that is in petrol engine lubricants, designed for scavenging out the carbon particles.
ZDDP is NOT needed for STOCK cammed flatheads, due to the low pressure of the valve springs. However, if a high performance cam and the matching high pressure springs are used, then yes, it is wise to either add ZDDP or use an oil with it already mixed, such as Kendall 20-50. If you add ZDDP, you must follow the instructions to the letter. It has been found that adding too much can be as injurious as not enough, due to the ZDDP actually displacing the oil film between the lobe and the tappet.
Much BS surrounds the topic of ZDDP, and it has been found that most of the damage caused to cams comes because many of todays aftermarket cams are ground on chinese billets. They may be ground in the US, but the fact is that chinese billets are composed of a lower grade powdered iron than US made billets, and they have a lower Rockwell (hardness) rating than US made billets.
Moral of the story.... when buying an aftermarket cam, check with the grinder, NOT the seller, as to whether the billet used was American or chinese. Go with the US billet, and use an oil ready mixed with ZDDP.
Incidentally, Valvoline 20-50 racing oil does indeed contain over 1200ppm of ZDDP, but it is missing several scavenging and cleaning additives required for a street engine. I would not want to do more than 300-400 miles between oil changes if using that product. A good street oil with ZDDP should go 1000+ miles, or more if an oil filter system is used.
 
In response to Jeff's comment.
The 92 TBI Chevy 350 I had used around a quart in 2000 miles with 226K on it. I had a 1987 305 which used a quart in 3500 miles. My 2006 grandprix with a buick 3.8 in it uses around 1/4 of a quart in 4000 miles and I have 35K miles on it. I had a 1986 Tbird with the 3.8 and it used a quart of 10W40 in 300 miles, the engine had 130K on it.

I also know for a fact GM will repair any engine under warranty which consumes more then 1 quart in less then 2,000 miles. Personally I think 1 quart in 2K is A LOT for a new engine but its not 1 quart in 600.


I am not a Ford or GM guy, I figure since I don't make the product or own stocks in either company it shouldn't matter to me whos name is on it. I have no problem buying a new Ford or GM if I like the product. I will also admit I like Subaru's cars A LOT because of the AWD system and the horizontally opposed engines they use.


40 Deluxe : I thought pistons had a little rib in the ring groove to keep the rings from rotating? At least I swear I remember seeing this in my service manuals to my two Yamaha ATVs.
 
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