Ultimate Motor Oil Thread or Why we hate CJ4/SM oils

[JFairman]

I think if you just shake up the oil container every month or two that would keep some of the additives from settleing out on the bottom.
Keep the ingrediants mixed up and shelf life may be longer.

[RWebb]

iff it is not an issue involving degradation (chemical) rxns... it's generally a good idea to do what the manf. tells you

if not, then why buy from a manf. that you don't trust...

but, I bought the SL m1 from Sprawl mart (see post above) w/o knowing its age. I have enough m1 for one more oil change and then I'll be making 5 hour trips to Portland to pick up some boutique wines... I mean oil.

[PatrickB]

Originally Posted by delaneyd

Question for Cnavarro---I have an 83SC with 105K miles , all original and does not leak--at all!!!. I have been using GTX 20W50 for years , but since I don't drive it much ( less than 2500 miles/yr ) I only change the oil every 12-18 months. Being in Alabama I think 20W50 would be my best choice , but what would you use??? Seems like my best choice is BP or Swepco 306 , but tell me which between the two and what weight.

Easy! Mobil 1 V-Twin 20w50. Specifically designed for motors that sit for extended perids of time, and already LOADED with Z&P, and best of all, recommended for oil testing engineer guru Charles Navarro! I've used it in my 3.2 for the last 8k+ miles with good results! Yeah... it's more expensive, but I don't think you can go wrong with this product...

[KNS]

Okay, I found the correspondence with Castrol, I was off - not two years but five:

Thank you for contacting Castrol North America.

There is no shelf life for Castrol Motor Oil, however we would suggest that
for maximum protection and performance, the product be used within 5 years
of the date of manufacture. Regardless of the storage conditions, moisture
can get into the product via osmosis through the plastic.

You can determine the date of manufacture by locating the fill code on the
bottom of the back panel. It is composed of a series of letters and
numbers, with the first five characters being the most important.

For example, if you have C04001...., the "C" would represent the plant
location. The five digits '04001' represents the date of production. The
numbers 04 represent the last digits of the year (2004) and the '001'
represents the day of the year, based on 365 calendar days, on which it was
produced (January 1).

For C9001 '9001' represents the date of production. The number 9 represents
the last digit of the year (1999) and '001' represents the day of the year,
based on 365 calendar days, on which it was produced (January 1).

Thank you again for your interest in Castrol, The Technology Leader!

Castrol Consumer Relations

[RWebb]

we're probably pretty safe with 5...

thx for digging that out

[cnavarro]

I have a stock pile of motul semi-syn 505.01 vw spec oil for my two newer VWs to last me about 3-4 years. I don't see any problem with the oil sitting that long. There are bottles of m1 older than that at Autozone and Napa around me :-)

Hey Jim, sorry I missed you. It seemed as though every person at Rennsport was either from Pelican or Rennlist that stopped by!

[JWLindsey]

Just got done going from GTX 20W50 to BP 20W50 in my 176k '87 Carerra. Off the bat, I noticed greater oil pressure and a reduction in valvetrain noise. I hate to sound like some sort of deluded fanboy, but I swear the car seems to idle a bit smoother and pull slightly harder with the BP in the sump. Might all be perception and prevention of cognitive dissonance, but it does seem like cheap insurance if it keeps the cam lobes and bearings happy.

-JWL

[scottb]

After reading this thread and the one on Rennlist, my head is spinning.

I recently came across a supply of SL-rated 20w50. Can I safely use this oil in my 84 3.2L engine that is used on occasional weekends?

Thanks, everyone!

[Oh Haha]

I found this Kendall on the shelf at my local CarQuest. it's been there a while as there was actually dust on the containers. Is this the "good" Kendall? (According to my source at CQ, they have 50 cases of 20W50 at the local warehouse.)

[Steve@Rennsport]

Wayne:

Thats the "new" version to be clearly distinguished from the "old" Kendall GT-1 made in Bradford, PA and the current Brad-Penn oils made the same refinery from the same base stocks as the original.

[BLEW911]

In a post on Rennlist it is stated that Castrol engines will be seriously dirty inside even though the oil looks clean.The detergents not doing their job? While the OLD Kendall oil always looked dirty but the motors were clean inside. When switching from Castrol to Brad Penn you can expect LOTS of this gunk to come free and clog thr sump screen. Also oil consumption increased while the rings cleaned and reseated.
Experts....what do you say?

Don

[cnavarro]

Someone asked about a product being marketed, Zddplus. I got back an email from its creator, and they do not add any detergents to the ZDDP concentrate. I haven't looked at some of the other new found super-concentrated ZDDP products floating around, but one thing is very obvious to me. Every product previously sold to boost ZDDP, be it STP or EOS, always had roughly an equal amount of detergents to offset the affect of ZDDP in reducing the TBN of motor oil. I'll have to go back through the various SAE journals to find exactly where it is, but it is in there that you have to have additional detergency because of the breakdown of ZDDP in peroxides and its interaction with combustion byproducts to form sulphuric acid. (don't quote me on that, but going from memory, I think that's how it works or in that order). For once, I will have to say that more is not better, especially in this case. If you do choose to use this product, be sure to do UOA and keep an eye on your TBN, as the detergency reserve will be depleted much faster than without the use of this product or compared to supplementing with EOS or STP, as you are drastically changing the balance of additives in the oil.

[RWebb]

"you have to have additional detergency because of the breakdown of ZDDP in peroxides and its interaction with combustion byproducts to form sulphuric acid."

- why not just more buffers?

[donstevens]

Originally Posted by BLEW911

When switching from Castrol to Brad Penn you can expect LOTS of this gunk to come free and clog thr sump screen. Also oil consumption increased while the rings cleaned and reseated.
Experts....what do you say?

Don

Nonsense. In 99% of the cases, there will be no such drama when introducing a superior oil.

First of all, the dirt that you reference is the beginning of sludge which is really the residue left behind when the base oil breaks down or "boils off" for lack of a better term. The poorer quality of the base oil, the quicker this occurs. Over 15-20 years of petroleum oils, all street engines get some of this to some degree. If your car has had 3000 mile oil changes it's entire life, this build up will not be too bad.

When a new oil with superior cleansing abilites is introduced, the cleaning will occur but it will be gradual. Like water smoothing rocks in a stream. In 99% of the cases, there will be no large chucks flaking off and no cloggong of the sump.

This is another reason to make used oil analysis part of your lubrication schedule.

Don

[donstevens]

Originally Posted by cnavarro

Someone asked about a product being marketed, Zddplus. I got back an email from its creator, and they do not add any detergents to the ZDDP concentrate. I haven't looked at some of the other new found super-concentrated ZDDP products floating around, but one thing is very obvious to me. Every product previously sold to boost ZDDP, be it STP or EOS, always had roughly an equal amount of detergents to offset the affect of ZDDP in reducing the TBN of motor oil. I'll have to go back through the various SAE journals to find exactly where it is, but it is in there that you have to have additional detergency because of the breakdown of ZDDP in peroxides and its interaction with combustion byproducts to form sulphuric acid. (don't quote me on that, but going from memory, I think that's how it works or in that order). For once, I will have to say that more is not better, especially in this case. If you do choose to use this product, be sure to do UOA and keep an eye on your TBN, as the detergency reserve will be depleted much faster than without the use of this product or compared to supplementing with EOS or STP, as you are drastically changing the balance of additives in the oil.

I agree. More is not always better.

I don't endorse the use of any ZDDP additive specifically for the reason Charles states above. Extra additives (of any kind) throw off the additive balance of the original oil. Period. There have been several oils listed in this thread that are excellent choices for the unique challenges of 911 engines. Simply use one of those products and forget about trying to improve them.

Finally, if you have used and continue to use ZDDP enhancers, I also agree with Charles that UOA is an essential tool when using such products.


Don

[cnavarro]

I emailed back the manufacturers of the ZDDPlus and pointed out to them that they should be aware of the problems with a high Zn and P with low detergency and possibly suggest that users should do UOA to determine the proper drain interval for oil when supplemented with their product. Likewise, suggesting the use of an oil with higher detergency designed for longer drain intervals would be a good suggestion - maybe something with a starting TBN of 10 or higher, but still, the TBN reserve will be used up quick.

In addition to the reduction of Zn and P, there has likewise been a trend to decrease detergency of oils if you look at the trend in VOAs after seeing hundreds of them. If you add too much Zn and P to these low detergency oils, you end up with a condition where oil needs to be changed very often, like with racing oils in street use, or if a longer drain interval is used, engines will sludge up and acid will attack the bearings. The sludge problem was something addressed way back in the early 70s at the same time as cam and lifter problems cropped up when they started to mess with Zn, P, and detergency levels.

There are TONS of excellent SAE papers that document everything. It's a shame they are not public domain so that everyone could read them, without having to pay of course.

[carreraken]

Any retailers on the West coast sell BP oils?

[hcoles]

Ken.... I got the contact of Bayside Oil Co. in Santa Cruz... that's the closest one they mentioned to me... I'm in the general area of San Jose... I would think there would be a closer one to you maybe in Sacramento.. if you respond to the correct link BP will get back to you. Give your city and zip.

[RWebb]

Originally Posted by cnavarro

There are TONS of excellent SAE papers that document everything. It's a shame they are not public domain so that everyone could read them, without having to pay of course.

- Nothing prevents someone from writing a review article that summarizes these papers and then posting that. It can include brief quotations and copy some graphs and still be an original work. In fact, that is what scientists do all the time. You've done something along that line in this thread.

I have to sympathize with the SAE wanting to recoup some of their operating costs. For many scientific societies, the cost of the journal is the most expensive thing they do. And many old - ah - curmudgeonly scientists will not read articles on computers - it's paper or nothing. Hence the online site attempts to subsidize the more costly print journal. I imagine it is a similar situation (tho with more $$) for an engineering society.

[carreraken]

Originally Posted by hcoles

Ken.... I got the contact of Bayside Oil Co. in Santa Cruz... that's the closest one they mentioned to me... I'm in the general area of San Jose... I would think there would be a closer one to you maybe in Sacramento.. if you respond to the correct link BP will get back to you. Give your city and zip.

Thanks hcoles, I'll try contacting them.

Ken