[smaman]

Its time to change the oil on my 71 TA with original unrebuilt motor and I was wondering what kind of oil people would suggest. I've used standard Valvoline 10w40 but have heard some people use Rotella. Comments or suggestions would be appreciated.

[74 SD455 Formula]

I use Royale Purple synthetic sae 10w-40 in my SD-Formula and my 72 HO 455 GTO. Fo the record this topic of discussion has been posted a couple of time before.

[contos20]

I have been using Royal Purple for many years in all my "special" cars. Just heard about this stuff. I will probably go to this when I get my engine from Butler pending more information about it.

http://www.z-alt.com/

[takid455]

I use 10W-30 w/ cam shield zinc additive. may switch to 10w 40 in the SD.

[Region Warrior]

Valvoline 30w in my 400hp 400 FB for 17yrs. Only drive during the warm months.

My street/strip FB, 5w30 Valvoline syn with a can of Pro Blend.

Been think'n bout use'n Mobil Delvac 1300 Super 15w40(GM's oil for Duramax diesels).
Costs me 4.60 a qt.

[SD73]

I use Redline's 5W-40 synthetic. Lots of zinc built in.

[Brewster]

Rotella has been my Oil of choice for many years now and recommend it for any second generation car.

[2manyT/A'S]

I've heard that it's NOT a good idea to put "plastic" oil into a motor with miles on it.

It tends to get past "seasoned" seals/gaskets & can/will cause leaks.

Should be OK for SD's as nobody really drives them.

[Harry71GTO]

Owner's Manual calls for either 30W or 10W-40. I used Valvoline 10W-40 for years but I just switched to Rotella 15W-40. I have 7000 miles on my rebuild.

[smaman]

Originally Posted by 2manyT/A'S

I've heard that it's NOT a good idea to put "plastic" oil into a motor with miles on it.

It tends to get past "seasoned" seals/gaskets & can/will cause leaks.

Should be OK for SD's as nobody really drives them.

I was wondering if anybody would bring that up. A few years ago I had my TA at the pure stock drags and one of the original GM engineers of the motor took an interest in the car and mentioned that synthetic oils were not the best for untouched HO engines.

[74 SD455 Formula]

Originally Posted by 2manyT/A'S

I've heard that it's NOT a good idea to put "plastic" oil into a motor with miles on it.

It tends to get past "seasoned" seals/gaskets & can/will cause leaks.

Should be OK for SD's as nobody really drives them.

It's OK for HO's as well as I drive it like I stole it as well as the SD. You must have me confussed with Brewster.I drive mine and he looks at his ( HA-HA ).

[guccieng]

swepco. full of the good stuff, especially for hyd flat tappet cams. http://swepco.net/lubesite/products/h306.htm

[Father&Son73T/A]

Originally Posted by 2manyT/A'S

I've heard that it's NOT a good idea to put "plastic" oil into a motor with miles on it.

It tends to get past "seasoned" seals/gaskets & can/will cause leaks.

Should be OK for SD's as nobody really drives them.

Been using Royal Purple 10w40 in the L-75 73 TA and in my 79 W72 with just turned 22k miles for a few years now.
The 73 drips about 2 drops every two months,which is what it did when we bought it in 04.
The 79 doesn't leak a drop,really,so I don't believe the old wives tail about synthetic in an older higher mileage engine,could be wrong,but I'm betting quite about on it I think

..........oh,and no need to add EOS or any other type of ZDDP additive,it's all in RP..
Give this man a call if you like,he told me to post it anywhere,nice guy.

As a corporate policy, we do not publish amounts or specific formulations in our products.
I'm curious as to what you consider to be an acceptable ppm of zinc and phosphorus and also curious as to where this level was determined / obtained?
What / who is publishing a specific percentage to determine that this is adequate for engine protection?
I am getting this question repeat times and I'm curious who is generating this so that I can address it on a global scale.
I'd appreciate your feed back on this.

I am a Mechanical Engineer and also a certified lubrication specialist with the STLE (Society of Tribologists and lubrication Engineers). I am not aware of a minimum amount as the different suppliers of the additives have different treat rates to obtain the similar wear protection performance.

I guess what I trying to say is this.
If Oil A has X ppm of zinc and Oil B has Z + 100 ppm of Zinc - it is a false conclusion that Oil B will have better wear protection. The additive packages just do not work that way.

For your older flat tappet engines in your TransAm's 455 and the 6.6L 400, we recommend our RP 10W40 or 15W40 Street API Engine Oils for stock engines.
These oils are still made to the older CI-4+ / SL API Service Rating - not the reduced CJ-4 rating for the new 07 and up diesels with the new restrictive DPF /. Catalytic Converters. so they have a very stout antiwear package that has excellent wear protection for your flat tappet cams.
RP does not recommend the addition of any additive to our oils and no break in additive is going to increase the wear protection of our Synerlec Additive Technology

The Royal Purple 10W40 and 15W40 has 1300 ppm of zinc and phosphorus but also contains our ashless Synerlec Technology which increases the oil film strength 4 times the oil film strength as compared to other diesel engine oils.

Cheers,

David

Royal Purple Inc
David Canitz
Mgr - Tech Services
1 Royal Purple Lane
Porter, TX 77365
281.354.8600
281.354.7600 fax
713.725,7207 cell
dcanitz@royalpurple.com

[Mirk]

I read a list somewhere that had a line up of all oils on the market that contain zinc molly and phosphorous. On the list I saw all oils posted here. The only discernible difference I could make out between all these oils that was published (I think maybe HotRodder or Car and Driver magazine or something. I was waiting in the mechanic shop) was the PRICE.
I repeat the only visible difference was the price. They all had the same additives and claim of protection but one oil was significantly cheaper than all the others.
VALVOLINE VR1 IS MUCH MUCH CHEAPER with the same Zinc molly and phosphorous additives.

I use Valvoline VR1 in my 67 Ford, 60 Bel Air, 72 Firebird (Before I sold it) and now my 72 Trans Am.

Perhaps Royal Purple is a better oil in some regard, but I change my oil every 3,000 miles religiously myself, in all my cars, so I really do not think the oil gets used enough for any difference to be noticeable.

What do you guys think?

[njsteve]

I use the Rotella 15w40 in all the old cars I have ('72 455HO, '70 426 Hemi, '75 350 Pontiac) and I add the CamShield zinc additive in. I like the CamShield additive as it comes highly recommended and can be mixed for various purposes (high concentration for break-in, or regular concentration for already run-in engines). Also, its made by a local chemist here in New Jersey, and I like to support the local businesses here.

http://www.cam-shield.com/

I have stopped using synthetics in my old cars after I had the original 350/300 hp Chevy in my Z11 Camaro start leaking from the rear galley screw-in plugs after I switched to Mobil 1. The car ran drip free for over a year on 15w40 Rotella, I changed the oil one day to Mobil 1 10w40 and within 2 days I had drips under the car that resembled a bad rear main seal. Pulled the inspection cover from the trans and saw the oil weap pattern from all of the rear oil plugs (which had been nice and tightly sealed previously). I can't tell you how much fun it was to have to remove the trans three times to get the back of the engine finally sealed up. We had to fully remove all traces of oil from the threads and then epoxy the plugs in place and then let it cure for 2 days, before it finally worked. It was as if the synthetic oil molecules were so small that they infiltrated the cast iron and kept giving an escape route to the oil.

By the way, that was the same engine that I lost a cam on during break in while using the newer reformulated (less zinc) oils back in 2003. In 30 years I had never lost a cam, especially on something as simple as a stock Chevy smallblock. I hadn't known about the oil chemistry change at the time, as it wasn't widely publicized back then and I paid the price for it.

From now on I'll stick with the good old dinosaur oil for the good old dinosaur cars.
:-)

[guccieng]

not to change the subject, but just as folks started having cam problems due to the change in oil additives, now we are having problems with rubber parts in the fuel system with increased methanol. another situation like njsteve said: "it wasn't widely publicized back then and I paid the price for it".

[Father&Son73T/A]

I run M1 XP(extended performance) in my cars with roller cams,ie my 99 TA 48k mi.,96 Regal 146k mi.,92 Escort 221k mi.with M1 filters,no need to change for 15000 miles,no oil burn or for years now,total cost per V8 near 50.00 at Walmart changing my self......once,for 15k miles.
Multiply the cost per oil change/time every 3000 miles,I come out ahead price and protection.
The RP get's changed every two years in the second gens,I only put 1500 miles a year if that on them,the price difference is worth the protection and not haviing to add ZDDP additives,works for me.
By the way no Mobil 1 product has had sufficient ZDDP for flat tappets since 2004...

[smaman]

I dug through my old magazines, and found the Feb 08 edition of Muscle Car
Enthusiast had an oil article. In regard to synthetic in old cars it said:

"The most asked question about engine oil for musclecars is the compatibility with the new synthetic grades. A fully synthetic, or a combination of a mineral/synthetic blend, can be used in any engine. The early synthetics that were introduced approximately 15 years ago had a slightly different swell rate for rubber seals, and became known for creating leaks in an engine that had the seals swelled to mineral oil. But that problem has been long corrected, and swell rates are nearly the same for mineral and synthetic oils."

[guccieng]

it mentions "can be used", but makes no comparison to performance, which is what most of us are looking for.

[Mirk]

Good find Smaman. That clears up that question.

As far as comparison on performance, do minute differences really matter or create cause for notice when oil is changed so frequently? I mean every 3,000 miles.
I dont know about you guys, but when I change my oil, it is still pretty clean and usable. I figure as long as the oil has a zinc molly and phosphorous blend and is changed often that it should preserve the engine. Thats my thinking on it anyways.