I read somewhere that 10w40 weights and higher do not have to meet the lower zinc requirements for modern emission systems.

Shell took the zinc out of their oils just like everyone else though.


______________

   

hi   if you are looking for  lucas oil products they are sold I auto zone stores     dwa

On Shell Rotella T :

"Only the 15W-40 and 5W-40. Those grades are NOT bound to the <800 PPM standard to be rated as an SN. The 10W-30 is SN rated and that grade is required to have less than 800 PPM. The detergent levels in these oils are way higher to pass the CJ-4 qualifications. Detergents are polar molecules as is ZDDP. They fight for the same space and reduce the coverage of ZDDP on the extreme pressure loaded parts. This is why diesel oils have higher levels, they have to to provide similar protection."

That's post #638 of this thread:

http://www.corvetteforum.com/forums/c3-tech-performance/2484100-list-of-flat-tappet-oils.html

The next to last sentence is important.




|UPDATED|3/16/2016 8:19:41 AM (AZT)|/UPDATED|


______________

   

I had my engine re-built about 2 years ago and the guys that re-built it recommended I use only Brad Penn SAE 20W-50 oil as it has one of the highest levels of Zinc/Phosphorous on the market. I don't live on the mainland but have no problems buying it here.

______________

$9.99 per quart!  Much cheaper from Summit.


______________

   

I use 10-30 Castrol in my engine and ZDDP additive, that I purchase through Amazon.

http://www.amazon.com/ZDDPPlus-Engine-Additive-Phosphorus-Bottles/dp/B006LB70SW/ref=sr_1_1?ie=UTF8&qid=1459191813&sr=8-1&keywords=ZDDP

______________

(click to see a larger image)


"It Takes A Little Longer To Do It Right"
"It Takes A Lot Longer To Do It Again"

This is what Pennzoil oils said in 2012.

An API SM rating will have the reduced zinc content (800-850ppm) while those such as the Pennzoil Outdoor Motorcycle Motor Oil in both SAE 10W-40 and SAE 20W-50 with the API SH will have 1100-1200ppm zinc.

Other oils containing higher zinc levels will be any oil with a diesel rating, API CI-4 or CJ-4.

The Shell Rotella SAE 15W-40 contains 1100-1200ppm zinc and Pennzoil Racing Motor Oil SAE 25W-50 has 1980ppm zinc.

I could not find any specification from Pennzoil on their products. 

One Pennzoil issue that is not reported much and I bet has not gone away is it depends on location the oil is manufactured to be sold in and the time of the year.  There are different additive packages for it so it is difficult to know what you are getting from Pennzoil.  I saw some test results from supposedly independent labs that show anywhere from 800ppm to 1800ppm for the same supposedly oil. 

Also Racing oils are designed for racing fuels not street fuels.  There is lots of different opinions on the harm or benefit of using Racing oils in street machines as the frequency of changing oils in a racer is a lot more than you want to do in your street machine.

Oh by the way I have read in a couple of oil forums that most sealant material used in pre-1992 engines does not like Synthetic motor oils.  Just thought I would through that into the mix.  I personally do not use synthetic oil in my 82.

Racing oils have less detergent in them.

Here is a website for the guys that are anal about their oil.  Some good info though.

www.bobistheoilguy.com



|UPDATED|3/31/2016 11:20:02 AM (AZT)|/UPDATED|


______________

   

FYI, If you going to add a thick additive do it when changing oil and add it to say a 1/2 quart of oil or in my case a 5 qt container and shake it up to make sure it gets distributed.  If it's just poured in on it's own it's gonna just cling to the side of the block and flow to the bottom of the pan. 

______________