AMSOIL Z-Rod for Classic Cars

[Jordan]

I was speaking to another Pagoda owner/member last weekend and he said he has switched to this oil which has been specially formulated for older classic cars and high performance cars. 

http://www.amsoil.com/shop/by-product/motor-oil/gasoline/z-rod-20w-50-synthetic-motor-oil/?code=ZRFQT-EA

Just wondering if anyone else uses this or has used it and has any comments. 

[Tyler S]

Metric Motors suggests 20 w50 castrol with a ZDDP (zinc) additive for all of their rebuilds. The Amsoil takes adding the additive out of the equation. One less step. Oils formulated for diesel engines also have a high zinc content.
I use castrol and add Rislone.

[Jordan]

Tyler, I also used Castrol 20W50 up until a few years ago when I changed to Shell Rotella T 15W40 because I found out the Shell had a higher concentration of ZDDP.  I know these formulations keep changing and that may be different yet again.  Castrol recommends their Edge 5W50 for classic cars with flat tappets.  It contains 1250 ppm ZDDP.

I called Amsoil and they told me the Z-Rod oil contains 1400 ppm ZDDP.  The Rotella T contains 1200 ppm, as I just called them again. I also realize one is synthetic and one isn't.

I was asking about the Amsoil because it seems to have a few other properties that would be advantageous to our older cars, such as the rust prevention when they are sitting all winter.  Just curious if anyone was using this product and their experience.

[Benz Dr.]

I've been using Amsoil 15 W 40 para synthetic  in my combine ever since it was new in 1983. This engine looks like new inside. Back then, everyone thought it was snake oil and now every oil company makes some sort of synthetic product. Amsoil is a very high quality product. Over 30 years of use has more than proven it's worth to me.

 This is one of the few companies that has a full line of products.

 

[Jordan]

Dan, does that mean you use it in the Red Rocket?

[Benz Dr.]

The whole car is running on synthetics. The ZF 5 speed and the LSD are very rare options and I only use the best lubes I can find for them. I also run syn ATF in the power steering and 10 W 40 in the engine. I also use synthetic grease.

[MikeL43]

I use Valvoline VR1 20/50 racing oil which claims it has a "high zinc formula also protects push rod and flat tappet engines" in my 250 SL.  They don't give the percentage of zinc in the oil but I seem to recall someone saying 1200.  I also used this oil in my old TR6 which had solid lifters.  I also used the diesel oil which was recommended by someone but decided to go with the Valvoline Racing oil as it was a little easier to find locally.   Someone please let me know if there is a reason not to use this oil.  I also found that the synthetic oil tended to leak out of the TR 6 engine quite a bit more than the regular oil.  Of course since it was a British car it was required to leak a bit as it was "marking it's spot". 

[Steve.k]

Dr. Benz:  I just purchased a 1971 280SL and like yourself, I’m in Ontario.   I’ve been looking for the right one for over a year and I’m going to baby it, but drive it.   I’d like to change the oil myself and have been reading the hundreds of posts on the subject of oil.  As you know, there is no consensus on this with as a many opinions as brands of oil.  Given we’re in the same climate and market, what brand, type and grade of oil do you use?
Thanks in advance,
Stephen

[Benz Dr.]

I use more Super Syn 15 W 40 than any other type of oil. It's a partial synthetic that you can get at any NAPA store.

New oil formulations have removed most of the zinc because it was found that it was slowly poisoning the converters. Since our cars don't have converters you are very safe using high zinc oils which protect vital moving parts in barrier lubrication applications such as rocker arms, valve stem tips, and cam lobes. Any moving part that isn't lubed by oil pressure falls under barrier lubrication and when you look at it you will find that's most of the internal moving parts of our engines.

I used to be an AMSOIL dealer back in the early '80's so I'm familiar with their products and I can tell you it's very high quality product. Don't use this stuff on a fresh engine or it won't break in properly. 

[Steve.k]

Thank you sir,  I’ve been looking for a high zinc oil in a 10W40 grade (since that was the original oil spec).  There are choices in 5W30 but I’m concerned that’s too thin for our engines.  Valvoline Max Life for example has high zinc content but 10w30 is only available up here.   
Just to clarify, The Super Syn you refer, is that the diesel oil?  Does Shell Rotella still have high ZDDP?

[thelews]

  Does Shell Rotella still have high ZDDP?

Yes, use it in all my vintage.  It's in new packaging, Shell Rotella T4 triple protection

[Steve.k]

Thanks For confirming that John.  I know oil has been discussed ad nauseum here, but a lot of the discussions were years ago and formulas change, companies change, etc. and thought it would be worthwhile to update the knowledge base. 
Is there any concern with 15w40 in colder climates?

[mrfatboy]

I just switched to Valvoline vr1 20w/50. I was using Rotella t4 15w/40. Both have zddp levels of 1200ppm from what I have read.

Metric motors recommends Castrol 20w/50 with a ZDDP addititive.

Dave Gallon told me the he and Motoring Investments use Castrol 20w/50 (I don't think they use additive. )

20w/50 seems to be the recommended weight for our San Diego climate.

I wanted an oil that has a high zddp level without using an additive.  The VR1 fit the bill at least for me. YMMV😜

[Benz Dr.]

Thank you sir,  I’ve been looking for a high zinc oil in a 10W40 grade (since that was the original oil spec).  There are choices in 5W30 but I’m concerned that’s too thin for our engines.  Valvoline Max Life for example has high zinc content but 10w30 is only available up here.   
Just to clarify, The Super Syn you refer, is that the diesel oil?  Does Shell Rotella still have high ZDDP?

I'm under the impression that any 15 W 40 is diesel rated. I'm not aware of the actual ZDDP content but I suppose I could find out.

[Benz Dr.]

I did a bit of research and found that AMSOIL Z Rod was rated number three as one of the best oils for preventing wear. This was out of a list of 40 popular oils. What I also found out is that more zinc doesn't always equate to more protection and adding zinc to fortify your oil may actually weaken its ability to prevent wear. Z rod has 1,400 PPM of zinc which is more than adequate to protect your engine so I would recommend its use.

[Steve.k]

I’ve come across a couple of threads from other car forums that have some detailed lists of oils for older cars with flat tappets. 

This one http://www.sccoa.com/forums/showthread.php?136304-What-oil-brands-offer-the-best-protection-***Good-read*** ranks them in terms of overall protection and lists the ZDDP content. 

This one is also thorough but does’nt rank them https://www.corvetteforum.com/forums/c3-tech-performance/2484100-list-of-flat-tappet-oils.html

The Amsoil Z Rod appears on both lists as does Royal Purple and Lucas Oil. 
Interesting info with several good choices. 

Back to you Dr. Benz :  which weight is best for us in the northern climates?  10w30 20w50 or the original 10w40?

[Benz Dr.]

That's the same write up that I saw so you can see what's good. I use 10 W 40 in my car and I think that would be OK for most.

I remember working on a local diesel, a 123 300D, back when I first got started. The valve cover was leaking so I pulled it for replacement and couldn't believe what I saw. Almost all of the cam lobes were worn off  and even though you really couldn't hear it, you could sure feel it. It was slower than a 200D and it smoked heavily. When I asked the owner what kind of oil he was using he told me 10 W 30. What ever it was, it wasn't anything close to what he needed and basically his engine was junk.

So, in most cases you never really notice when something like steel toed shoes are working but you sure notice when you stub your toe wearing street shoes.

[Steve.k]

Wow, that’s a very compelling story and shows the importance of selecting the right viscosity.  Thanks for all the recommendations.  I’ll definitely avoid anything less than 40 weight. 

[thelews]

The weight of your oil also depends on the quality of your engine.  A fresh rebuild will use a different weight than an engine with 100K miles on it.

Also, lots of oil discussion on www.bobistheoilguy.com

[Jack Jones]

I use Mobil 1 15w50 racing oil that is recommended for flat tappet engines that requires high zinc, containing 1,300 ppm of zinc. Easy to find and reasonably priced.