[GT182]

A.W. go with 20w-50 Valvoline that has zinc in it. A Pontiac engine builder, and his dad who's also an engine builder, said to use in in my 66 GTO's 400 he built. I've been using it faithfully, along with a Purolator L30005 filter. No problems at all.

No 10w-40 Valvoline here either. Only High Mileage 10w-30 semi synthetic. I've stocked up with 5 5 quart jugs just in case that disappears too. I refuse to use any other brand because of all the paraffin in them. Yes, that's where the sludge comes from. Which is probably why synthetic oil was born.

[Formulabruce]

I recall my Tractor using 15-40 . I don't think its going away, But, I can see the price going up.

[Joe's Garage]

Originally Posted by burd

Walmart has oil, plus I pick up a few trailerpark girls while I’m there.
No more pf24’s either.

Say hello to Patty if you see her..........

[JimFB400HO]

I suppose I need to research what synthetic oil is. I've used nothing but Pennzoil conventional in every vehicle and other engine I've ever owned for many decades. I think the lawnmower is the only 10-40 I use but the straight 30W required by GM for my '68 Firebird seems to be getting more difficult to find.

[Formulabruce]

O'rielys has plenty of Rotella 10-40
The "straight 30W" oil you buy for your '68 is not even close to what it once was as its loaded with cleaners etc.
I do not believe I have seen that spec in a 68 owners manual, but if so, Im sure it doesnt agree with the service manual.
At the dealership, we served '68's and always put in 10-30.

[Sirrotica]

Jim, since I operated a Pennzoil service station in the late 70s, early 80s I also use nothing but Pennzoil. About 15 years ago I switched to using their 10W30 platinum synthetic in all the gasoline engines, it's been just fine for everything I use it in this includes my air cooled lawnmowers.

On the Bob is the oil guy forum, Pennzoil synthetic is among the highest rated oils produced by a major oil producer, Amsoil may be better, but Pennzoil is plenty adequate for most everything with a gasoline engine.

Again, the oil is nowhere as important as keeping it filtered to a very high standard. I use by pass filters to accomplish that task. Oil that is properly filtered has a 3-4 time extension of it's life, just because you don't have to keep dumping it to get rid of the fine solids that pass right through a conventional oil filter. You do change oil because it's dirty and contaminated, not because it's no longer capable of lubricating any longer. Keeping oil clean also extends the additive package life, no downside to a better oil filter than OEM issue gives us.

The by pass oil filters not only extend the life of the oil, it cuts engine wear by 7-8 times over what a conventional oil filter can remove from the oil.

I now worry about my oil filter, and what it is capable of removing more so than what brand oil I use, and how it will hold up under adverse conditions. most of the major brands of oil are of good quality at this point in time.

I hope this helps you with a decision on your oil, and perhaps considering a more efficient oil filter.

[JimFB400HO]

Formulabruce, I think I would probably be fine with 10-30 like you mention and may have to go with it some day.

I do add ZDDPlus to the 30W to get the zinc and phosphorus back to the old levels. My '68's engine has never been rebuilt so I have to adjust the oil and gas to make up for the old cam and tappets and the original valves , seats and compression.

The straight 30W comes with a story: When I took my '68 (with the 400HO) into a dealer for warranty service in 1969, I mentioned the engine slightly "tapping" The service manager asked me what weight oil I was using. I told him 10w30. We got my owner's manual out and he pointed out a footnote to the recommended oils. I can't remember if the Service Manager underlined that in my book 52 years ago or if I did. Ever since then, (now with 183k on the odometer) I've used straight 30W in the summer. And, yes you are correct, the '68 Service Manual does not have that note.

[JimFB400HO]

Sirrotica, Thanks for the good info. I suspect a zinc additive also be needed on the Pennzoil synthetic? Hopefully ZDDP would be compatible with it.

I have always been obsessed with clean oil, changing it every 2,500 on the '68 and 3,000 on every other vehicle I've owned. (That's a lot of changes on my GMC Van with 353k miles.)

[unruhjonny]

Originally Posted by Sirrotica

Back in the mid eighties GM issued a bulletin that the additive package used in 10W40 could cause sticking of the oil rings on the piston, resulting in oil consumption problems. I never had used it before then, and never recommended it to my customers, or used it myself.

This stuck with me overnight (I read it yesterday);
I wonder if that was just a possible issue with the additive being used at that time.

I thought I had a small quantity of Castrol GTX 10W-40 just for my Firebird... and now you guys have me thinking I should maybe keep an eyey out to always have a small supply.

Pennzoil oil doesn't get much discussion here, becasue quite frankly, I don't really see it all too often. I had tried a bunch of brands, and noticed that Castrol (in the white containers) seemed the best for my Firebird and high strung Quad4 HO.

[Sirrotica]

Originally Posted by JimFB400HO

Sirrotica, Thanks for the good info. I suspect a zinc additive also be needed on the Pennzoil synthetic? Hopefully ZDDP would be compatible with it.

I have always been obsessed with clean oil, changing it every 2,500 on the '68 and 3,000 on every other vehicle I've owned. (That's a lot of changes on my GMC Van with 353k miles.)

Jim, there are 2 ways to keep oil clean, and you choose to keep replacing it as oil gets contaminated. I used to do it that way too, but have since found out that a by pass oil filter that takes all the contaminants out down to 5 microns actually saves money over the long run, especially if you keep a vehicle well over 100,000 miles as you seem to, it's totally your choice on how you keep your oil maintained.

The low mileage vehicle in my fleet is 120,000 miles 99 GP 3.1, next is LS2 05 GTO at 145.000, 1988 212,000 mile 7.3 IH diesel S1600, 1995 chevy 3500HD 6.5 turbo diesel at 250,000 miles, 1993 K3500 6.5 turbo diesel at 272,000, and finally a 08 Vibe at 325,000 miles. I keep my stuff a long time and the by pass filters make it a whole lot easier, and cheaper to keep the oil as clean as possible, for as long as is possible. Typical oil changes 35-40,000 miles every 3-4 years. IMO filters are more important than what brand of oil you choose to use. The synthetic is always more stable at higher temps than conventional oil.

As far as ZDDP, that isn't the only additive that works with flat tappet cams, but it is the least expensive. If I were you, I'd call Pennzoil tech line, and ask them what one of their oils they recommend for flat tappet cams. I've called them in the past and have gotten good advice from their staff.

[The Champ]

Originally Posted by JimFB400HO

Sirrotica, Thanks for the good info. I suspect a zinc additive also be needed on the Pennzoil synthetic? Hopefully ZDDP would be compatible with it.

Mobil 1 has multiple oils that already have satisfactory levels of ZDDP in them.

They specifically recommend their 15W50 for flat tappet cams. Here is a link to this oil:

https://www.mobil.com/en/lubricants/...obil-1-15w-50/

If you go to the link, on the right hand side, there are some quick links. One of them titled "Zinc and Phosporous Levels" will take you to a chart that lists every Mobil 1 oil and has the levels listed.

Other street use oils with over 1000 PPM Zinc and Phosphorous are:

0W40 FS, 5W50 FS X2, 5W40 Formula M, 5W40 Turbo Diesel

[Old Goat Racer]

At 77 YO I have Old School ways . I change oil and AC filter in my 2017 Silverado w/6.2 (gas) every 3000 miles. But after 4 1/2 years it only has 9000 miles on it.
So my question is, does AGE play a part in an oil change ? My last oil change had 1 year and 9 months on it.
NO, the truck is NOT for sale ! OGR

[jhein]

So would the best thing to do be to use a full synthetic oil in the weight of your choice and just use a zinc plus additive?

[Vid]

Originally Posted by jhein

What about Lucas with the zinc, moly phosphorus additives?

https://www.summitracing.com/parts/luc-10683-1

Lucas “Hot Rod” oil is the 10-30 I use in my current 350 Pontiac and plan to continue using in the hydraulic flat tappet 455 I’m building. No complaints.


Sent from my iPhone using Tapatalk

[Sirrotica]

Originally Posted by Old Goat Racer

At 77 YO I have Old School ways . I change oil and AC filter in my 2017 Silverado w/6.2 (gas) every 3000 miles. But after 4 1/2 years it only has 9000 miles on it.
So my question is, does AGE play a part in an oil change ? My last oil change had 1 year and 9 months on it.
NO, the truck is NOT for sale ! OGR

First of all I'm 68 YO, so I had to go against every thing I did for many years making my living wrenching on cars and trucks when I switched to by pass oil filters on my own vehicles. Running oil for years and 35-40,000 miles is a tough thing to do when you've done the OEM oil and filter changes all your life.

That said, the only way to be certain of what the oil is like is to pull a sample and have analysis run.

My experience is changing oil in my vehicles runs over 3 years many times because of using a by pass filter. I've never had any adverse experiences because of oil aging.

Two things that do affect oil is contamination of water/coolant, or fuel. Any oil that has fuel or coolant in it is not useable. If it's free of both of those contaminants, and clean your oil should last a long time and still be adequate to lubricate the internals of your engine.

With OEM filters the oil becomes contaminated with solids that the filter cannot remove, it then has to be drained to stop abrasion of internal components by the solids. Remove the solids with a better filter and you extend the life of the oil, and engine.

I have oil in my 05 GTO that is 5 years old, and my 6.5 diesel truck is 4 years old. The GTO is going to Norwalk on Friday pulling a trailer with the pit vehicle on it, with the same oil in it, and I'm not the least concerned. The oil has over 30,000 miles on it also, the car has 145,000 on it and I'm the original owner.

People that run by pass filters commonly run oil over 3 years, with no adverse consequences.

[unruhjonny]

Originally Posted by jhein

So would the best thing to do be to use a full synthetic oil in the weight of your choice and just use a zinc plus additive?

I think that 'the champ's last post suggested the additive wasn't required if the correct synthetic was used to begin with.

I have understood in the past that synthetics like tighter tolerances;
Maybe that's pure bunk, but that's what I've heard.

I have also seen synthetic blends that are labelled for "higher mileage" engines... maybe that's worth looking into as well.

[Sirrotica]

Originally Posted by jhein

So would the best thing to do be to use a full synthetic oil in the weight of your choice and just use a zinc plus additive?

There is such a thing as too much ZDDP in oil, I would consult with the manufacturer to see what their recommendation are for your application with flat tappet cams.

[Vid]

I usually run 10-30 synthetic in my Dakota pickup that I use primarily to tow my boat with. It has the small 4.7 V8 and really has to work hard to get the job done since we go from Reno up to Lake Tahoe where there’s 4000’ elevation change. Doesn’t overheat but the temp gauge gets it’s exercise, and I hit 5800rpm+ more than I care to on each trip.

Couple of weeks ago I thought it’s time to change the oil and with these 100 degree temperatures we’ve been seeing, maybe going to 10-40 isn’t a bad idea. Autozone and O’Reilly’s didn’t have any, I don’t shop at Walmart so I went on Amazon and ordered some Pennzoil 10-40 and a WIX filter. So yep maybe 10-40 is being phased out. Most new cars like the really thin stuff so it makes sense. Now, what viscosity do those Tesla’s use, hmmm…

Years ago I never thought motor oil would be something I’d have to worry about getting worse in quality, in fact I thought it would only improve with technology. However when I saw some 5 quart jug on the Autozone shelf boasting on it’s label that it’s “NOW MADE FROM 100% NATURAL GAS” that certainly convinced me otherwise. Funny that it didn’t mention one reason why that might be a good thing. If you didn’t know any better, a colorful label for Chinese food stating “TWICE THE MSG AS THE LEADING BRAND” might sound like a good thing.


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[Sirrotica]

Originally Posted by Vid

I usually run 10-30 synthetic in my Dakota pickup that I use primarily to tow my boat with. It has the small 4.7 V8 and really has to work hard to get the job done since we go from Reno up to Lake Tahoe where there’s 4000’ elevation change. Doesn’t overheat but the temp gauge gets it’s exercise, and I hit 5800rpm+ more than I care to on each trip.

Couple of weeks ago I thought it’s time to change the oil and with these 100 degree temperatures we’ve been seeing, maybe going to 10-40 isn’t a bad idea. Autozone and O’Reilly’s didn’t have any, I don’t shop at Walmart so I went on Amazon and ordered some Pennzoil 10-40 and a WIX filter. So yep maybe 10-40 is being phased out. Most new cars like the really thin stuff so it makes sense. Now, what viscosity do those Tesla’s use, hmmm…

Years ago I never thought motor oil would be something I’d have to worry about getting worse in quality, in fact I thought it would only improve with technology. However when I saw some 5 quart jug on the Autozone shelf boasting on it’s label that it’s “NOW MADE FROM 100% NATURAL GAS” that certainly convinced me otherwise. Funny that it didn’t mention one reason why that might be a good thing. If you didn’t know any better, a colorful label for Chinese food stating “TWICE THE MSG AS THE LEADING BRAND” might sound like a good thing.


Sent from my iPhone using Tapatalk

The reason natural gas is used is simply it's cleaner when extracted from the ground, it doesn't already have soil mixed in when it's extracted as crude oil does.

[Old Goat Racer]

OK "Sir" What oil filter would you recommend for my 6.2