wanted some opinions. i have a 69 firebird 400, with 89k miles. i have always used regular oil, but am thinking of using mobil one. any issues with changing oil on older car, with miles like this. thanks

Not good to mix. After all those years with the one kind of oil it would be impossible to get all the residue out. Bearings do not like multiply kinds of lubrication. You could get a lump of sludge from the old oil disolve in the Mobil One and then you have two types of lube in one area. Not good. You could switch to something that's similar to what you have been using.

I changed to Mobil 1 in mine , took it in for some service after about a month , maybe 150 miles, the mechanic ,who races older cars and almost only works on older cars advised against it...I`m now using regular Pennzoil instead again..

Due to bad luck, Pennzoil would never be in any engine that I own, This goes back many years and maybe they changed their formula(parifin)I have about 1000 miles on my new engine (probably more)I have a change of Rotella 15 W 40 heavy duty ready to go in. From what I have heard from many people, and I think Yellowbird was one this is the oil to use in our flat tappet engines?????

I`ve used Pennzoil since 1968, it was also the brand my dads dealerships used from 1967-1990 (after 1990 I dont know), I still use Pennzoil in my daily driver...in The Caddy I owned I used Mobil 1

I have no doubt that there were many excellent motor oils available that were engineered for our engines when our cars were new. The engines are now engineered differently, overhead cam or roller cam vs. flat tappet. Oils are engineered differently as well. EPA regs cut the phosphorus level in oil to reduce emissions, which meant removing ZDDP.

Diesel rated oils do not yet have to meet the spec. Rotella is still friendly, but the picture is changing.

Some racing oils have ZDDP content as well, but at a higher price than Rotella T. Be certain that your Rotella T is the CJ-3 spec, not the new CJ-4. ZDDP is gone as of October when the switch to CJ-4 is mandated, even in diesel oils, so either stock up now or plan to switch to a racing oil or add one pint of STP Oil Treatment at every oil change to any API or CJ spec motor oil. STP has 1% - 5% zinc compounds.

thanks, so regular oil it is. im in so cal, never under 30 degreees, so 10-40 grade?

A Shell rep recommended 15W-40. I don't think too many of our 'birds see winter duty, so for most this should be fine.

What would be the reason to not use 10W-30?

That's about the time I started using Pennzoil too. I figure I'm up to about 400 oil changes in my vehicles without any engine work required. I am switching to Rotella in the Firebird due to the need for ZDDP.

I'm using Rotella in my old cars too. 10W-30.

What is Rotella, and ZDDP?

Rotella is a brand that most auto parts have. Regular oil that has sufficient ZDDP. Not expensive at all. Many oils do not have the ZDDP that the older engines need.

Zinc dialkyl dithio phosphate (ZDDP, ZnDTP, or ZDP) is a family of zinc salts of dithio organophosphates. They are soluble in nonpolar solvents, so they easily dissolve in mineral and synthetic oils used as lubricants. They come under CAS number [68649-42-3]. In aftermarket oil additives, the percentage of ZDDP ranges approximately between 2-15%.

The alkyl groups can be branched and linear alkanes between 1-14 carbons length, 2-butyl, pentyl, hexyl, 1,3-dimethylbutyl, heptyl, octyl, isooctyl (2-ethylhexyl), 6-methylheptyl, 1-methylpropyl, dodecylphenyl, and others.

A mix of zinc dialkyl(C3-C6)dithiophosphates come under CAS number [84605-29-8]. List of other examples with their CAS numbers is here.

The main use of ZDDP is in anti-wear additives to lubricants (eg. greases, motor oils). To date it is the dominant anti-wear agent, present in most machine and motor oils in amount of about 1%. However for motor oil applications the amount of ZDDP has to be minimized, as the zinc and phosphorus emissions damage catalytic converters, .

Brad, Check out this discussion: /forums/ubb...dp&topic=0&Search=true#Post52638
Jim

This topic I’m quite familiar with. In the Beemer MC forums this turned into heated debates. Some of these guys and gals sphincters are so tight... well you get the picture. It’s been some time since I was in a Beemer forum, but as I recall BMW advised dealers not to use syn oil in bikes under warranty. Regardless of this warning many owners including myself use 100% syn oil in our horizontally opposed big twins.

Contrary to some beliefs, it’s ok to use 100% synthetic motor oil in older cars. The most common misgiving is it can’t be used with conventional. That use to be true with synthetic back when it was a relatively new product. The synthetics of today are found on the market as blends of syn and dino.

Synthetic oil is superior to conventional oil in many ways. It doesn’t break down as quickly as dino, and it has better adhesion to critical surfaces. That’s why oil change intervals are further apart, and start up is much easier on effected parts. The one draw back I personally experience is syn does seep past older gasket materials faster than dino. I almost forgot, syn oil also has a broader range of viscosity.

I will not argue the point of the oil for diesel motors. Vikki covered the points of using these dino oils. Like she said, buy’em up now for those will fade into history thanks to the EPA. Thanks for the tip on STP Vikki. I didn’t know it still carried a percentage of zinc.

As far as brand goes, that’s up to you. Different folks have brand loyalty; others don’t give a rats ars. I prefer Castrol. I use the syn blend 10-40 in the convertible, and I use the Castrol dino 10-30 (in winter) and 10-40 (in summer) for the cammer. I’d use the syn blend in the cammer, but I have to get it sealed up better. It likes to leak that undercoating and it’s less expensive than syn blend.

Hmm, is it getting warm in here?

Ok there Beeker.

Cut and paste.

Alrighty then.

uh oh, everyone watch the fine print on the Rotella that you buy. Few weeks ago I went to Walmart here in Los Angeles to stock up on Rotella. I bought a few years worth. Well when I read this post last night I went out to the garage to check and the stuff I got is CJ-4 which Vikki says is not really what we want. I've seen Rotella in a bunch of other stores but haven't checked their version.

So I headed back to Walmart and now have a few years worth of STP oil treatment to go along with my Rotella CJ-4. STP stuff says ZDDP included on the bottle though I didn't see a percentage.

The CJ-4 is a standard, among many, that the oil needs to meet.
Just because it says it meets CJ-4 on the bottle is not a bad thing. The bottles that I have from Walmart also say they meet CJ-4 and a bunch of other standards.

right, there are many standards listed on there but I thought Vikki said we need to make sure to get the CJ-3 standard because CJ-4 does not have the ZDDP?

Walmart also has 30W rotella but it doesn't list CJ-3 or CJ-4. does this stuff have the ZDDP we want?

I did read on another post that the rotella 30W had enough ZDDP in there. However, it sounds like CJ-3 stuff is different than CJ-4 stuff so I'm wondering if there's a similar giveaway marked on the 30W.

This is what I got at Walmart;

CJ is a diesel standard. By itself it does NOTHING to benefit our cars over API spec. The Rotella T CI-4 Plus had the most ZDDP and excellent performance specs...CJ-4 has virtually none. I also have a nice stock of Rotella T CJ-4 that I missed the new cert on. CJ-4 is widely being slammed as not worthy for engine preservation. If you have this, add STP Oil Treatment. (My earlier post referenced CJ-3, um...that's a model of Jeep, not an oil spec. It WAS CI-4, CI-4+)

http://corporate.lubrizol.com/Press...nding%20Calcium%20Sulfonate%20Thickeners

15W-40 has the advantage of the fastest oil pressure build at startup.

API CJ-4 oils exceed the performance criteria of API CI-4, CI-4 PLUS, CH-4, CG-4 and CF-4 and can effectively lubricate engines calling for those API Service Categories.

While CJ-4 oils are being developed specifically to be compatible with exhaust aftertreatment devices, they will also provide better soot-handling capabilities and oxidation control. In short, they’ll offer increased overall performance and better protection for the new engines – and will protect older vehicles, too.

Extensive testing by Lubrizol has demonstrated that API CJ-4 is backward compatible, which means API CJ-4 oils can be used in older-model vehicles as long as the oil analysis is closely monitored and the appropriate maintenance schedule is maintained based on lubricant quality.

Since i only drive mine at 60* +, i use Valvoline 30W.
Tried Pennsoil a couple times, but pressure would drop about 5-10lbs after only 1000 miles.
Switch back to V-30, and it wouldnt drop for 3000 miles.

This year will see 6000+ rpm's, so i'm gon'a use Valvoline 20-50 racing.
After helping guys at the track last 2 seasons, this seems to be the oil of choice.
Can tell you for sure it made a big diff on brg life on Ray Cox's 7000+ rpm engine.
He used Pennsoil 20-50 racing before. That crap is like motor honey.
Gained a tenth and 1.5 mph with no over changes.
He'l never admit it cause it was my idea.

If you read page 14 of the article, you will see a synopsis of ZDDP in automotive motor oil. It's clear that API automotive spec does not care about the older cars. Read on, and you'll see that in truck fleets the turnover is only 10% so they make more effort to protect older engines. If CJ-4 was the same as CI-4+, they would not have come out with a new rating. They removed/reduced the ZDDP to meet new emission restrictions.

There are many different protective qualities, but most all sources agree that low ZDDP levels can cause the premature destruction of flat tappet cams.

so Vikki, the picture Jim posted shows that particular rotella oil meets both CJ-4 and CI-4+ standards. You said CJ-4 has no (or low) ZDDP while CI-4+ has high ZDDP. What does this pictured oil have for ZDDP?

so is diesel oil better than regular 10w30?

down at work we have 15w40 diesel oil on tap, and a guy ran it for three or more years he said in his truck, he said when he took it apart to inspect it the bearings looked like new still.

i always heard diesel has more detergent in it.

According to the Material Safety Data Sheet for STP (http://www.setonresourcecenter.com/msds/docs/wcd0001d/wcd01d35.htm)Ingredient Name (ZNCPD) ZINC DIALKYLDITHIOPHOSPHATE 4%

Brings 2 questions to mind-
Is the % enough to protect our cars?
Is STP compatible with Synth Oils?

MSDS available from STP says 1% to 5% Zinc compounds by volume. When diluted in a crankcase, I think that comes out to about .2% ZDDP average. 1993 spec for automotive oil was .12%, and flat cams were uncommon. Current API spec for automotive motor oil is .08%, and reports of flat cams are widespread. Up and coming API spec is .05%.

CJ-4 is .12%. Add the STP to it and ZDDP will increase to .32%, maybe half a bottle would be better. Use of GM's Engine Oil Supplement would be fine too, perhaps better, it is listed as <5% ZDDP by weight.

http://www.thecloroxcompany.com/products/msds/armorallstp/stpoiltreatment.pdf

http://www.v6racing.com/msds.pdf

STP SynPower Oil Treatment has less than 1% ZDDP.

The builder of my new engine recommended Shell 15-40 Rotella. I had never even heard of it until I asked him for recommendations.

Should be able to crank for first time this Sunday if all goes well. Daughter AND grand-daughter have been in town for the past week, so I've been a bit tied up.

Can someone break this down?

15W-40(cl-4, ch-4, cg-4, cf/sl)
Used in GM's Duramax diesels.

Thanks

The combo's of numbers and letters are standards that the oil meets. They are not like a list of ingredients like one would assume from some of the postings in this thread.