: Questions about pre 00 Northstar oil change and use of additives



blooddragon78
01-07-14, 09:42 AM
I'm about to do the first oil change in the next few weeks on my 98 Seville since I got it. I was going to go Valvoline, and I know 10w-30 only in a pre 00.
I know oil brand comes down to a personal preference, but I've seen information about the newer oil service designations don't have the amount of zddp in them
that the old ones did.
Being that the N* is a flat tappet cam I know the zddp can play a role in the cams life. Was thinking Valvoline VR-1 as I've read it has 1300 ppm zddp, but can not locate it in 10w-30.
Is there an additive I can use along with conventional Valvoline to up the zddp content a little? I've never been an additive in my oil kind of person, and I dont want to put any thing in this motor that may have the potential of damaging it.

Ranger
01-07-14, 09:55 AM
There are several additives (just google ZDDP), but you'd be better off finding an oil with higher ZDDP levels (there are several of those as well) if that is what you want, though I think the lower rates are still safe.

JoeTahoe
01-07-14, 10:06 AM
I use Shell Rotella T 10w-30 in mine and recomend useing a diesel oil in any thing with a flat tappet cam. Its your flavor on oil. but the diesel oils are higher in zddp. Brad Penn has oils higher in zddp also

Submariner409
01-07-14, 10:46 AM
Most of the so-called "high mileage" oils carry a higher ZDDP load, and all of the HD fleet and marine oils do. Shell Rotella, Pennzoil Long Life, Chevron DELO marine oils, Quaker State Defy, .......... lots of options. Google each refiner of interest and dig deep for the spec sheets on their oils.

Or, if you like blending your own potions, maybe 5 quarts of a good 10W-30 and 2.5 quarts of a HD 10W-30 synthetic from Joe Gibbs Racing or AMSOIL.

"Sub, mix conventional and synthetic ???" Sure - on any oil brand label, what is the percentage of the oils contained in a "synthetic blend" ? It could be anywhere from 1:99 to 99:1 conventional:synthetic and still be called a blend.

Take a look at the chart and figure out the API service rating of the latest oil in use BEFORE the model year of your car. That's what oils were originally recommended by GM. In the OP's case, it's SG/SH.

EDIT: Something to consider . . . . Uncontrolled use of ZDDP additives WILL kill a catalytic converter.

blooddragon78
01-07-14, 12:48 PM
Take a look at the chart and figure out the API service rating of the latest oil in use BEFORE the model year of your car. That's what oils were originally recommended by GM. In the OP's case, it's SG/SH.

EDIT: Something to consider . . . . Uncontrolled use of ZDDP additives WILL kill a catalytic converter.

To much zddp is one reason why I'm leery of just throwing any ol additive into it. I'd rather just find a well known trusted oil that has what these engines need, or a trusted additive.
I'll have to look but I think we only carry 15w-40 Rotella at work.

Valvoline's site recommends full synthetic high mileage for my car when using there oil selector, but again not available where I live, same as there VR-1 line(over the counter grey bottle, not the black non street use stuff) which from what I've read would be ideal for these engines.
May have to break down and order online lol.

stoveguyy
01-07-14, 04:29 PM
Is it true 10-30 is better for flat tappet cam wear issues vs 5-30? I prefer 5-30 for winter use but many have said 10-30 is ok if u park in garage. Some say 10-30 is fine even if u park outside. But folks here with 94-97 era cars are dwindling down.

Submariner409
01-07-14, 04:51 PM
The advertised viscosity range of an engine oil makes very little difference in flat tappet lifter/cam wear.It's the additive package.

BUT - Viscosity ranges are recommended for specific engine design and use. I would never run a 15W-40 oil in my Northstar, but that's all I run in a big cube boat engine. Different engines, different duty.

10W-30 worked perfectly fine for me in Southern Maine in January in a Chevy 327. Your 1996 Northstar would be fine also.

Remember - that left hand number is the theoretical cold start viscosity. It's all the same viscosity at over 180 degrees oil temp. One of the main reasons makers went to 5W- and 0W- is the tiny, tiny fraction of less power required to roll over the engine and run it at low oil temperatures - ANY decrease in reciprocating parts drag is a theoretical fuel mileage increase - CAFE.

stoveguyy
01-07-14, 04:52 PM
Thought I read the base stock in 10-30 is different than 5-30. Something about shear stability and so on? I changed rear VC gasket 2 yrs ago and inspected my lobes closely. I thought they were ok but my dad said they looked slightly scuffed on the high point

Submariner409
01-07-14, 05:01 PM
Put the base stock thing in an envelope and hide it. Cam lobe tip wear/lifter bucket scuffing in a 1996 DOHC engine with XXX,XXX miles ? No engine, no cam, no part is forever - oil be damned. (Your 140,000 miles was a pipe dream 40/50 years ago - the engine would actually be nearing its second major overhaul back then.)

EDIT: For lengthy discussions on shear, viscosity change, additives, 4 ball wear tests and the like, get into the AMSOIL website and read up on what they subject oils to during testing.

blooddragon, If you really want to get into oil quality, use, opinion, innuendo, flaming, truth, lies and flights of fancy - log into www.bobistheoilguy.com and put on a suit of armor.

Ranger
01-07-14, 09:37 PM
Is it true 10-30 is better for flat tappet cam wear issues vs 5-30? I prefer 5-30 for winter use but many have said 10-30 is ok if u park in garage. Some say 10-30 is fine even if u park outside. But folks here with 94-97 era cars are dwindling down.
Consider this. GM didn't even spec the Northstar for 5W30 until 2000, when it got roller followers.

For what it's worth, I have always used 10W30 (and still do). Ran it in a flat tappet engine back in '81 after sitting overnight at ORD while I worked the night shift at -27. It started (reluctantly) and ran fine without any problems. Still run it in all 3 cars, 2 Northstars and a 3800, even in the latest -20 degree weather.

blooddragon78
01-07-14, 09:54 PM
blooddragon, If you really want to get into oil quality, use, opinion, innuendo, flaming, truth, lies and flights of fancy - log into www.bobistheoilguy.com and put on a suit of armor.

LOL I've ran across that site a couple times in the last few days. So as a general consensus do most just not worry about the fact newer oils don't have the amount of zddp in them that older oils did?
Honestly, I prefer Valvoline for good ol dino, Mobile 1 for synthetic. At 257,000 miles should I really care how much zddp is in the oil if I'm doing changes when the car says I need to?

I really do appreciate all the info you guys are loaded with on here. Hope to one day know the N* as well as I do my ol SBC's! :cheers:

Ranger
01-08-14, 10:24 AM
I have to believe that they would not lower the ZDDP levels low enough to cause damage to every car in America with flat tappets. My supply of SL oil is almost depleted. Once it's gone I'll be using the current grade and won't be loosing any sleep over it.

drewsdeville
01-08-14, 11:13 AM
Personally, in my experience, engines with flattened cam lobes are extremely rare. Zillions of flat tappet cam engines (most of which are pretty old and high mileage, mind you) still roaming the country. When I do see a worn cam, it's the result of an actual problem, such as a coolant leak into the crankcase. I'm not sure I have ever witnessed a camshaft severely worn under normal conditions.

I think the real world data (number of actual failures) tells us the lab data on this topic grossly exaggerates it - tells us there is a problem that doesn't exist (the same over analysis our government likes to do in many other areas, which we resent, yet somehow it influences us it when it comes to oil wars). The units of data are so small, it makes the differences seem bigger than they are. A 30% change of a fractional value is still a fractional value. We have seen the terrible lab data over and over. If it's the doom and gloom they say, where are the real world results to support it?

blooddragon78
01-11-14, 12:15 AM
Not trying to beat a dead horse here, but I think I found my oil of choice for my Cadi. :horse:
I've always preferred Mobile 1 for a synthetic, and happens to be there High Millage oil is SL rated with 1100 ppm of Zinc.
Normally I wouldn't use synthetic in an engine with this many miles on it, but since I've only had to add one quart to it since acquiring it in November I''l give it a go and see how she does. :thumbsup:

Submariner409
01-11-14, 10:32 AM
Mobil and Mobil 1 product is good oil. Several very respected automakers recommend it. Good choice.

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Personally, in my experience, engines with flattened cam lobes are extremely rare.

I'm recommending the earlier SH/SJ/SL rated oils based on the posted pictures in here, over the years, of dished cam followers and worn cam lobes in the pre-2000 Northstars - our primary engine in question.

I have built about 83 various marine engines of Olds 455 and GM 454 derivation, all using flat tappet cams, and all using some form of HD Fleet/Marine multigrade oils. To date I am unaware of any lifter or cam failures in those engines, and some are approaching 16 years of murderous use under some of the worst conditions imaginable. (You think we baby our car engines - to a waterman his boat engine(s) is his life blood - these workhorses receive the best in care and maintenance.)

drewsdeville
01-11-14, 12:31 PM
I have built about 83 various marine engines of Olds 455 and GM 454 derivation, all using flat tappet cams, and all using some form of HD Fleet/Marine multigrade oils. To date I am unaware of any lifter or cam failures in those engines, and some are approaching 16 years of murderous use under some of the worst conditions imaginable. (You think we baby our car engines - to a waterman his boat engine(s) is his life blood - these workhorses receive the best in care and maintenance.)

That's fine 'n dandy, but that this doesn't mean a daily driven automobile engine won't survive it's very different conditions without those specific fluids. I'm not sure what marine engines have to do with it.

In the scope of most forum threads, it's really, really hard to justify alternative fluids, filters, and other maintenance gear to an individual who has an well used engine that operates perfectly. "Don't fix what's not broken". This is exactly why oil wars exist. If there is no problem, what are you analyzing? If these problems actually existed, there'd be nothing to debate!

As far as the pictures posted here 'over the years', the frequency is so very small that we can't even suspect maintenance methods. Those examples are obviously very rare, and very isolated, and since most of the examples happened many years ago - they were also relatively young engines - which should raise a flag. We can't be sure of the conditions that have caused that - that's not a sufficient sample size to draw any kind of conclusion. NOW, if a significant number of members running SN grade were wiping out their cams, then we'd have something to talk about. But still, even at the current super-mega-terrible SN spec, and even at the age and mileage these flat tappets are approaching, these engines are still outlasting the cars in which they reside.

blooddragon78
01-11-14, 10:42 PM
I'm going to throw my $0.02 in since I started this thread. First let me say this is/was not to start an oil war, it came from my own research about my recently acquired N*, which I've learned is my first flat-tappet cam engine. I've always owned GM, and SBC's and BBC's up to this point. All of which were roller cam, even my BBC I built for my 79' short bed Chevy.
I don't think cam ware as a whole is a major issue because almost all car's since the 80's have been roller cam,General Motors and Ford both switched from flat-tappet to roller cams in the mid-'80s, imports have been doing it for how long? Very few engines I know of have been flat-tappet, N* being one up to the 2000 model year.

At the time for the few flat-tappet engines that were being produced still the oil had what was needed to provide proper friction reduction, and honestly who knows for sure with out long term research, current oil may be ok, but I'm personally a man of I'd rather use the closest thing to what the engine required when built to maintain it than throw what ever at it and hope for the best. Which brings us to the fact the oil has had a gradual reduction in friction agents these engines needed. It didn't happen over night, and the problems that may or may not arise from it are not going to happen over night.
If there is any thing I can do that may help extend the life of my engine, then I'm the kind of person that wants to figure it out and do it.

Get into the old Hotrod's and the niche group that has these old engines with the shall we call special needs any more and they all that I've met in my life use racing oil and lead additives to run there engine the way it was meant to be ran.

I'm at the elementary school level when it comes to learning about my Cadillac, and its to me amazing engine. I'm Thank full for any input I get to my questions, and to me as an ol SBC guy that's only dealt with roller cam set ups that don't have the cam ware issues that can be prone to flat-tappet I'm grate full for Submariner's input and experience with building engines and sticking with the old API service ratings and what he has observed in doing so.

mavric240
03-06-14, 11:03 AM
If anyone is looking for the Rotella T 10w30 I carry it at my work.