[b-man]

About 25 years ago when I was building my first Pontiac engine I contacted Ken Crocie at H-O Racing numerous times when he offered a tech question phone line for his customers.

During one of our conversations I asked him which brand of oil he recommended.

His answer was "on sale".

Buying whichever brand was on sale at a discount was his advice. Ken didn't have a preferred oil brand to recommend. For many years I was using Havoline 10w-30 in my daily driver 455, with a coupon I was paying $0.39 a quart for it. The inside of the engine always looked clean and I never had any oiling related issues.

Personally I've used numerous different brands of oil including diesel oils and all were more than satisfactory.

[72LuxuryLeMansLa.]

You can use the cheapest, recycled, no-name oil and it will work fine! The secret is that you have to run around the car backwards three times before you pour it in!

[dataway]

Most oils advertise a full warranty against an "oil related failure" ... my guess is not one oil company since the dinosaurs were alive has had to pay out a claim.

Only engines I've ever seen that NEEDED a special oil, were engines that were in a state of tune or modification that far exceeded the original design parameters of a stock engine.

As far as flat tappets go ... if you had old school US made cam core and old school US made lifters ... you could probably use any oil made and still be fine. Maybe it wouldn't go 150,000 miles, but it wouldn't wipe a lobe at 5,000 miles.

[track73]

I had some loud lifter noise on my 455 swapped into my 65 F250. Marvel Mystery Oil. Fixed it. I have used every brand of Oil From RPM Delo., Havoline. Q State ,McMillan,Sears, Wards,Pennzoil,Wolfs Head, Cam2, and 15 cent re refined oil back i n the 60's. I read one time that the government is the biggest single procurer of oil so all oils must pass their specs to be able to sell to it.

[Chief of the 60's]

Originally Posted by dataway

Most oils advertise a full warranty against an "oil related failure" ... my guess is not one oil company since the dinosaurs were alive has had to pay out a claim.

Exactly like oil filters. Yet the scaremongers will claim this and claim that about Fram filters. LOL!

[Fullsize455]

Originally Posted by dataway

Most oils advertise a full warranty against an "oil related failure" ... my guess is not one oil company since the dinosaurs were alive has had to pay out a claim.

To be fair, in the interest of an honest debate, this would be more due to the difficulty in proving that any failure was the fault of the oil itself, rather than a mechanical fault within the engine, or abuse, etc.. the cost to investigate and prove that would be far greater than most people will want to pay in the hope that maybe they'll get reimbursed later by the oil company. Most people know that's only just going to cost them more money and time in the end, as the oil company will of course fight any claim, with much more legal might than most people can compete with.

[Fullsize455]

Originally Posted by 68 461 Bird

What do you consider prolong high RPM? On a long trip (3-5 hours) at 65 to 70 mph, my engine is at 3200 RPMs.

That's fairly high for a diesel engine, but I wouldn't consider that high RPM. You can't ignore the context of my post, which was referencing race usage vs. street usage when talking about prolonged high RPM usage. 3200 RPM at a steady, low throttle cruise is not hard on an engine. Routinely giving it full throttle to redline is much, much harder on it, and diesel oil would not be approriate for that kind of abuse.

[Fullsize455]

Originally Posted by 68 461 Bird

I have heard this several times before and I am in agreement, but a lot of people seem to agree that the "lead substitute" is necessary if you are running an old engine that hasn't been upgraded with the hardened valve seats. What are your thoughts on this?

My experience is that it is totally unnecessary. I've run numerous non-hardened seat engines for many miles on modern fuels with no additives, and have disassembled many more, and have seen no conslusive evidence that there is anything to worry about on a street engine. I think it may be more of an issue on race engines, maybe on higher compression engines or engines that are regularly driven hard, but on my street engines with lots of miles I haven't seen it be an issue. Again, my '71 455 with 241k, never used any additives, and all but one of my valve seats looked pretty decent still. The one exhaust seat that was bad was on a cylinder that was running a little low on compression due to tired rings, and that cylinder was burning a good bit of oil. I suspect that contributed to the exhaust seat pitting, as the others all looked good.

I've taken apart a bunch of virgin, untouched engines that showed no sign of excessive valve seat wear either, despite running tens of thousands of miles on modern fuels. I think it's much ado about nothing, to be honest. I've seen too many engines run too many miles and have too little wear to think there's anything to it.

[Fullsize455]

Originally Posted by track73

I had some loud lifter noise on my 455 swapped into my 65 F250. Marvel Mystery Oil. Fixed it. I have used every brand of Oil From RPM Delo., Havoline. Q State ,McMillan,Sears, Wards,Pennzoil,Wolfs Head, Cam2, and 15 cent re refined oil back i n the 60's. I read one time that the government is the biggest single procurer of oil so all oils must pass their specs to be able to sell to it.

Yep. And how many of us have run a quart of Marvel or ATF mixed in with our oil to try to free up sticky lifters? How many of us have used a wide spectrum of viscosity oils in our engines to counteract excessive oil burning, try to bump up oil pressure on tired engines, and maybe even just because that's all we had left in the garage? How many of us have had old tired engines where the oil was heavily diluted with fuel due to blowby or excessive rich running, where the oil was broken down or old and thick or full of carbon, etc etc., and all these engines survived just fine? The idea that an oil of the recommended viscosity but with a slightly different additive package can destroy bearings quickly is just absurd.

[68 461 Bird]

Originally Posted by Fullsize455

That's fairly high for a diesel engine, but I wouldn't consider that high RPM. You can't ignore the context of my post, which was referencing race usage vs. street usage when talking about prolonged high RPM usage. 3200 RPM at a steady, low throttle cruise is not hard on an engine. Routinely giving it full throttle to redline is much, much harder on it, and diesel oil would not be approriate for that kind of abuse.

Thank you for your reply and was not ignoring the context of your post. I was mainly asking your opinion if you thought a steady 3200 RPM was considered too high for the diesel oil on a street driven classic. I have been using the ZR1 Vavoline 20W-50 in my street driven classics, wasnt sure if I should switch over to diesel oil or not.

[68 461 Bird]

Originally Posted by Fullsize455

My experience is that it is totally unnecessary. I've run numerous non-hardened seat engines for many miles on modern fuels with no additives, and have disassembled many more, and have seen no conslusive evidence that there is anything to worry about on a street engine. I think it may be more of an issue on race engines, maybe on higher compression engines or engines that are regularly driven hard, but on my street engines with lots of miles I haven't seen it be an issue. Again, my '71 455 with 241k, never used any additives, and all but one of my valve seats looked pretty decent still. The one exhaust seat that was bad was on a cylinder that was running a little low on compression due to tired rings, and that cylinder was burning a good bit of oil. I suspect that contributed to the exhaust seat pitting, as the others all looked good.

I've taken apart a bunch of virgin, untouched engines that showed no sign of excessive valve seat wear either, despite running tens of thousands of miles on modern fuels. I think it's much ado about nothing, to be honest. I've seen too many engines run too many miles and have too little wear to think there's anything to it.

I appreciate you sharing your experience on this as well. It seemed like I was wasting my money but no one was ever able to tell me they tore their engine down and saw anything from using it or not, especially with the amount of miles you have run. Thanks for the advice!!

[geeteeohguy]

Originally Posted by GT182

I don't understand why anyone uses diesel oil on their gas engines. It's for diesel engines not gas. I used it at one time in my 79 Formula and it ruined the engine bearings. That's one of the reasons I only use Valvoline. You might think your doing your engine a big favor but it the long run you aren't. And I've heard that from a number of retailers and those that have used it.

Sorry for the rant but I hojnestly found out the hard way.

All due respect, as an automotive master tech with over 40 years of experience, this is not the truth. Look it up....do the research. The worst oil you can run in a street driven flat tappet engine today is RACING OIL, which lacks the additive packages needed to fight corrosion, acid build up, dilution, etc. Plenty of failed bearings on the street using that stuff. Been running Rotella and Delo for 12 years or more, and thousands of miles. When I tore down my '67 GTO in 2011 for a reseal at 90,000 miles on the rebuild, the bearings looked like new, as did the rest of the engine.

[TedRamAirII]

I have a hard time with Rotella 15w40. Nowhere in their literature is Diesel Motor OIL rated for Gasoline Engines. They do list T6 5w30 Multi Use for gas engines. Oil companies stand behind their product. If you have a gas engine and have a lubrication failure, that turns out to be CJ or CK rated oil that you used, they are not going to help you. If Shell tells you not to use it, do you believe them, or the guy that says they don't know what they are talking about.

[Sirrotica]

You can go too far with adding ZDDP, and it's been proven that more, isn't better. When there is too much ZDDP in oil it will have an adverse effect and actually cause scuffing components (flat tappet cams and lifters) to fail prematurely than the same base stock oil with less ZDDP in it.

I doubt that running diesel oil is going to cause flat tappet cam or lifter failure by itself, but I won't say it couldn't happen, cause I really don't know myself. Now ramp up the levels of ZDDP more than what the oil company puts in it when it's formulated (additives) and you can be running into problems that too much ZDDP causes.

Diesel oil has to deal with many times the amount of soot caused by a higher volume of blowby due to compression ratios near 18-22.5 to 1. and a fuel that doesn't burn as clean. Gas engines have soot too, but not anywhere near the volume in diesels. Stands to reason that the soot element alone is going to cause a different formulation of oil. Can the oil be interchanged on a gas engine? better to ask the experts from the oil manufacturer, than the experts on the internet

Most brand name oils made today have started using other friction modifiers because the feds wanted ZDDP cut back. If you do some due diligence you'll find that there are other chemicals that oil manufacturers can use to supplement the oil in a flat tappet application.

FWIW, if you really want to know what works for your application, don't ask on forums. When I have a lubrication question I simply call the oil companies tech lines. They know much more than anyone on the internet knows about their own products.

I had a problem in an air cooled application that kept seizing the pistons on a parking lot blower, causing it to break the connecting rod at high RPM. I called Pennzoil, gave them the rundown of the problem and the application. They recommended their 10W30 synthetic and the engine never tossed a rod after switching. BTW this was when synthetics weren't common place, and they were very pricey.

I know that no one wants to hear this, but one of the biggest enemies of engine oil and engine longevity is the junk filter system Detroit engineered. Just installing a better filter system is going to at the very least double the longevity of your oil and engine, likely 3-4 times over a standard filter system.

When you start removing solids from the oil 20-40 times smaller than the regular oil filter is designed to catch, it makes a huge difference. I didn't believe it until I switched on my own stuff, it flat out works exactly as advertised. The under 10 micron stuff is invisible to the human eye, but your engine knows it's there, silently wearing the internally oiled parts prematurely.

[68 461 Bird]

Originally Posted by Sirrotica

Can the oil be interchanged on a gas engine? better to ask the experts from the oil manufacturer, than the experts on the internet

FWIW, if you really want to know what works for your application, don't ask on forums. When I have a lubrication question I simply call the oil companies tech lines. They know much more than anyone on the internet knows about their own products.:

So then why should we listen to you?

There's a lot of inteligent people on this Pontiac forum with a lot of experience on what has worked for them and what has not. I would trust that information before I trust a large corporation that is only interested in making a buck.

[Chief of the 60's]

Because he was a mechanic at a stealership.

[68 461 Bird]

Originally Posted by Chief of the 60's

Because he was a mechanic at a stealership.

Hahahahaha

[Fullsize455]

Originally Posted by TedRamAirII

I have a hard time with Rotella 15w40. Nowhere in their literature is Diesel Motor OIL rated for Gasoline Engines. They do list T6 5w30 Multi Use for gas engines. Oil companies stand behind their product. If you have a gas engine and have a lubrication failure, that turns out to be CJ or CK rated oil that you used, they are not going to help you. If Shell tells you not to use it, do you believe them, or the guy that says they don't know what they are talking about.

Delo 400 meets the current SN standard for gasoline engines, so it is absolutely usable. I believe Rotella used to meet the old SF standard, which is absolutely acceptable for any old flat tappet engine. It doesn't meet the current SN standard, most likely due to zinc content, but they couldn't care less about testing it to meet an obsolete standard. Do you think Rotella is really that different from Delo oil? Do you think they've gone backwards with the new variants of it?

You have to understand, oils have not gone backwards in terms of their engine protection capabilities. They have advanced significantly over the years. However, they have also had to comply with ever more stringent emissions requirements, and in the case of diesel rated oils specifically, if you look at the different classifications, most of the changes are related to emissions. Consequently, the same has happened with gasoline engine oils. The oils with higher zinc content are not going to meet the current SN standard, and there is no point in testing or classifying new oils by old obsolete standards, and I suspect that is why Rotella is not gasoline engine rated any more. But if you look into all of this and what the ratings mean, you see pretty clearly that, just because an oil is not rated by the API for certain engine use to emissions requirements, that does not necessarily mean it is not perfectly acceptable for use in an old flat tappet engine.

And to address 68 461, I agree in some part about not blindly trusting what anyone has to say while they stand to gain from selling you a product. At the same time, they obviously have a wealth of knowledge, so getting info from them is certainly valuable, but you have to consider the source and seek out info elsewhere as well if you want to figure out what is definitively the truth.

Keep in mind that the oil companies will NOT ever tell you to use something that violates emissions requirements, nor will they ever tell you to use an oil that is not rated for gasoline engine use in a gasoline engine. However, as many of us here know firsthand from extensive personal experience, many diesel engine oils are perfectly acceptable to use in many gasoline engines. The oil company may not necessarily lie to you, but they also will never tell you to use something that is not appropriate based on the API certs, and thus you are not at all being told the whole story. Hence, research. Simply calling Pennzoil for a recommendation is foolish, just as simply asking in this one forum would also be foolish. If you really want to know, you have to expand your research to every source you can reasonably find.

[Fullsize455]

Originally Posted by Sirrotica

You can go too far with adding ZDDP, and it's been proven that more, isn't better. When there is too much ZDDP in oil it will have an adverse effect and actually cause scuffing components (flat tappet cams and lifters) to fail prematurely than the same base stock oil with less ZDDP in it.

I doubt that running diesel oil is going to cause flat tappet cam or lifter failure by itself, but I won't say it couldn't happen, cause I really don't know myself. Now ramp up the levels of ZDDP more than what the oil company puts in it when it's formulated (additives) and you can be running into problems that too much ZDDP causes.

Diesel oil has to deal with many times the amount of soot caused by a higher volume of blowby due to compression ratios near 18-22.5 to 1. and a fuel that doesn't burn as clean. Gas engines have soot too, but not anywhere near the volume in diesels. Stands to reason that the soot element alone is going to cause a different formulation of oil. Can the oil be interchanged on a gas engine? better to ask the experts from the oil manufacturer, than the experts on the internet

Most brand name oils made today have started using other friction modifiers because the feds wanted ZDDP cut back. If you do some due diligence you'll find that there are other chemicals that oil manufacturers can use to supplement the oil in a flat tappet application.

FWIW, if you really want to know what works for your application, don't ask on forums. When I have a lubrication question I simply call the oil companies tech lines. They know much more than anyone on the internet knows about their own products.

I had a problem in an air cooled application that kept seizing the pistons on a parking lot blower, causing it to break the connecting rod at high RPM. I called Pennzoil, gave them the rundown of the problem and the application. They recommended their 10W30 synthetic and the engine never tossed a rod after switching. BTW this was when synthetics weren't common place, and they were very pricey.

I know that no one wants to hear this, but one of the biggest enemies of engine oil and engine longevity is the junk filter system Detroit engineered. Just installing a better filter system is going to at the very least double the longevity of your oil and engine, likely 3-4 times over a standard filter system.

When you start removing solids from the oil 20-40 times smaller than the regular oil filter is designed to catch, it makes a huge difference. I didn't believe it until I switched on my own stuff, it flat out works exactly as advertised. The under 10 micron stuff is invisible to the human eye, but your engine knows it's there, silently wearing the internally oiled parts prematurely.

I'm curious about this far more advanced filtration system you seem to have found.. more details?

Also, do you have anything to back up your claims on other friction modifiers that effectively replace zddp in flat tappet cam engines? I've never heard of that.

Also, it's not so much the feds that demanded the reduction of zddp usage, it's the fact that it destroys catalytic converters. Yes, the feds mandated it as a result, but the damage to catalytic converters is the reason.

[tom s]

I used Baldwin by pass oil filters on my boats for years and swore by them,I just don't like the look of them in my classic car engine compartment,for me changing filters and oil is my choice.I have never had any oil related issues on any of my cars.Tom