: What Oil For Northstar Cams and Flat Tappets?

07-06-09, 01:43 PM
I've been researching what oil I should be using in my Northstar to prevent camshaft and tappet wear. API specs have reduced the levels of ZDDP in most of the new formulations and many people have started to experience problems with their cams and flat tappets in many different engines. It seems from my research that high levels of ZDDP (around 1200ppm+) combined with an that has a sheer rating of at least 3.5 should give the most protection. I've decided, as have many others, to begin using Rotella 15-40.

Here is an excellent thread loaded with info:


Also, a terrific site for researching different oils including VOA's (virgin oil analysis) and UOA (used oil analysis):


I've also found an aftermarket ZDDP additive that looks promising for those interested:




07-06-09, 03:17 PM
...........or you can spend no more money than a good name brand dino oil and shift to one of the major oil brands in 10W-30 designated as "Fleet" or "Long Life" use. (BB engines, not a 280 c.i. Northstar, are happy with the 10W-40 and 15W-40 equivalents) These oils are also rated for diesel use and so carry a higher ZDDP load, soot detergents, and anti-foam additives for HD use. They do not carry the usual starburst "gasoline engine" logo because the dear ol' EPA doesn't want us using high ZDDP oils after they mandated its decrease a few years back.

15W-40 IS NOT a good oil for a Northstar with its tight tolerances. Stick with a fleet or marine 10W-30, particularly if you live North of South Texas. 15W-40 is NOT "slipperier" than 10W-30. 10W-40 if you do a lot of trailer towing.

2000+ Northstars went to 5W-30 due to the shift to roller cam followers. DO NOT run truck oil in a 2000+ Northstar.

07-06-09, 05:42 PM
Hi Submariner409 -

Yes, it seems there is a lot of debate about the oil for flat tappets, hence the reason for my post. I would bet there are some very good oils called "long life" that would work well in the Northstar. If you know of one specifically, would you please share which one that is? The issue as I see it is that API certified oils available right now do not match the anti-wear properties/additives of oils available in the early 1990's when the Northstar was developed. From what I can tell, the forces acting on the tappets are relatively high (compared to a roller lifter) in our engines and we therefore need to be very careful to take necessary precautions. I've seen images posted on this site of worn cams and tappets so I know for sure this can be an issue for our engines.

As described in-depth in the first link I posted, the brand name of the oil is actually far less important than the standards and ratings the oil meets. It is quite confusing since there are many different standards out there, some are manufacturer specific and there are different standards available in the US versus Europe . . . However, some standards are much more specific in what they test for. The API standards appear to be fairly generic and the testing relatively loose . . . In that same link, the expert discussing the available oils did make this general statement "However, the best short rule of thumb (at least as I see it) is a sheer rating of at least 3.5 and meets A3/B3, A3/B4 or C3 . . ."

From what I can tell, the Heavy Duty oils, like Rotella are designed for extreme operating conditions of Diesel engines, but that does not automatically preclude their use in gasoline engines, if anything that should be more of a reason to use these types of oils. Their higher levels of ZDDP necessarily exclude them from the latest API ratings and the Energy Starburst, none of which matters to me since the Northstar was designed for oils with those higher levels of anti-wear additives not readily found today. Extra detergents and additives a problem? No, actually this sounds very good to me since those additives will help keep my rings clean thereby preventing blow by/oil burning and keep my compression where it should be . . . This is an issue faced by those big diesel engines too.

There are a number of folks on this site running Rotella with very good results. Also, this oil is being recommended for more and more engines as the benefits of Rotella (and similar HD engine oils) is becoming more well known. As an example, I have come to learn that quite a few people running high boost Subaru Boxer engines have started to run this oil with excellent results.

It seems to me that there is actually a very wide range of quality in motor oils, and that brand name alone says very little about an oil's performance. Those guys running big Diesel engines are careful to run only the really good stuff because they can't afford the down-time for repair of a failed engine. If an oil can withstand the stresses encountered in a big turbo diesel, it can certainly handle our V8's, and I think that is exactly the point!

From what I can tell, the worst thing the slightly heavier weight oil will cause is a very slight drop in fuel economy . . . For those concerned, the Rotella 5W-40 claims to improve fuel economy over earlier products.

What I found is that it is extremely difficult to find an oil with the needed high levels of ZDDP content - around +/-1200ppm minimum and also a minimum HTHS shear rating over 3.5. From my research, it seems that the Rotella 5W-40, Rotella 15W-40, Delvac 15W-40 and the Delo 15W-40 all meet these two criteria. Unfortunately, most manufacturers do not openly provide details regarding their anti-wear additive packs. Having said that, there is a very active message board called BITOG (www.bobistheoilguy.com) where it is possible to research oils and where many people are sending oil samples to labs like Blackstone for testing. These tests, although imperfect, can help us to get some indication of how an oil is constructed and what additives are being used in each.

I suppose I could have opted for any base oil meeting the recommended standards shearing standards and then added the aftermarket ZDDP additive product to it. Instead, I chose a known good, highly regarded/high performing oil with the appropriate additive pack already included from the factory. This is both less costly and easier to deal with from my point of view. Rotella is not an expensive or exotic oil and is readily available almost everywhere.

I would submit that anyone simply running a generic or "branded" newer API spec oil in a pre-2000 Northstar, and thinking they are doing all that's necessary to maintain this engine, would be well advised to do his/her own investigation into these questions of wear additives and how oil standards have changed over the last 15 years to draw their own conclusions about what is good for this engine vs. not.



07-07-09, 10:24 AM
As you opine, people should do some research into what they use to protect their engine: All this thread has been posted so many times over the years that we risk starting another "CF OIL WAR", but.........

I build Olds 455 and GM BB 454 engines for boats - racing, cruising, and heavy duty work. In those we run Pennzoil Long Life 15W-40 on various Engle flat tappet hydraulic cams and have never wiped a lobe or lifter. ("Never" = 23 years.) We also run (horrors) Fram HP-2 filters - big racing filters and MILODON 8-quart pans.

All well and good, but 15W-40 oil is too heavy for a temperate climate 280 c.i. engine built to tight tolerances. The pre-2000 flat cam follower N* engines call for 10W-30, and Pennzoil makes a fleet Long Life oil in that grade. The 2000 and later engines call for a 5W-30, but they have roller cam followers adjusted by static hydraulic adjusters. I run a WIX 51522 filter there. I will admit that, when I learned that GM was deleting the old black-bottle EOS due to EPA pressure, I bought 3 cases. At 1/2 pint per oil change, that will last a very long time.

07-07-09, 12:48 PM
Hi Submariner409 -

Thanks for sharing some of your experience and real world knowledge! I can see you have much more experience than I will ever have in tearing down and building engines. I have been trying to find the specs on the Pennzoil Long Life 10W-30 you mentioned but I haven't been able to find that product on the Pennzoil web site. I did find a link to the Long Life product line, but that grade is not shown - perhaps I'm just missing it somewhere? I would like to know more about this Pennzoil product. I did a quick search on BITOG didn't turn up much either. I do know that Rotella can be had in the 10W-30 as well, but is hard to find and I think it has less ZDDP than the 15W-40.


Also, from what I can tell from my quick review, the Long Life Pennzoil products do conform to many of the same Diesel ratings as the Rotella . . .

I've read about GM's EOS and others have said it was good stuff - not sure if it is still available or discontinued at this point.

From your point of view, what is the risk of using the heavier oil? For a cold start I don't think there's "much" difference between a 10W and 15W (judging by the API charts). Is the concern that at operating temps the oil will be too thick and not provide sufficient flow to the bearings?

Thanks again for sharing.


07-07-09, 06:27 PM
WooooHooooo!!! You got me on this one - that's the first time I've seen that new site, and 2 revelations: You're correct - no more 10W-30 Long Life and it also appears that 5W-30 Platinum has been replaced by 5W-40 Euro.

I'm going to Western Auto tomorrow and will see if there's any of either still on the shelves in quarts or gallons. Need to rethink my car oils.

There's still tons of the other stuff out there - Google for fleet and marine lubricant distributors. We get the 15W-40 in 55 gallon drums, but that's a bit much for your garage.........Find the Rotella 10W-30, or try the 15W-40 (but I'll stick to my guns: 15W-40 is not necessary in normal automotive use.)

The original GM EOS has been "reformulated" (watered down) to conform to EPA requirements.

EDIT: Just went back to your Pennzoil site. Looks to me like they changed everything. BTW, Shell/Pennzoil/Quaker State are all one and the same company now.

07-07-09, 07:34 PM
Something has changed radically in the Quaker State - Pennzoil - Shell websites. Very unfriendly and impossible to get to the commercial or heavy diesel lubricants pages. You are forced to stay within the U.S. passenger car lubricant offerings, and it won't let you get to the European spec 5W-40's and other HD Euro oils. I get the feeling that Big Brother is extending his watchfulness. It appears the EPA is now telling you, as an individual, what you can run in your car. They did it with Ethanol, now they're into motor oils.

Maybe I'm being quick on the trigger, but something has changed - a lot.

07-07-09, 11:32 PM
This is very interesting. I had noticed on the Shell site that, although I could find the HDEO section, there was very little detail or specs available regarding the oil itself. Not to get into politics or conspiracies, but at face value, since the US government now has a huge stake in GM, it would not surprise me if there was a desire to accelerate the burn-out of older engines to increase the rate/need for replacement vehicles . . .

So we still have the challenge. I did just install Rotella 15W-40 in my car and it feels very nice at speed, however, I've noticed the idle from a cold start is a little uneven compared to how it had been. I wonder if this has to do with the 15 weight? I found a couple of online places that will ship the 10W-30 in 1 Gallon containers here:



The first link is interesting, they carry a wide range of MIL spec oils, many of which I have never heard of . . .

I may just order up a few gallons of the Rotella 10W-30 and see how that does. Unfortunately, I think the 10W-30 may have lower levels of zinc.

Some folks on BITOG are recommending Mobil 1 High Mileage 10W-30 for our Northstars.


07-09-09, 10:53 AM
Went to Western Auto (my toy store) this AM.....Looked at all the Pennzoil containers and it appears that the oil bottles with the new logo and oil viscosities are dated as being filled in and after 3 February '09. So something has definitely changed and there is no more 10W-30 Long Life. Now there's 15W-40 Long Life and 15W-40 Long Life GOLD. Go figure. They still package a 5W-30 Platinum synthetic, however.

You can also look at 10W-40 Marine. It has a heavy ZDDP load for all the GM BB engines. If Rotella still packages a 10W-30 in fleet or marine specs that's worth a look also.

I can't see how the Rotella 15W-40 could have anything to do with a cold (cool) idle problem, but I still consider it to be too heavy for a Northstar.

07-12-09, 10:52 PM
Some folks over on BITOG seem to recommend the Pennzoil Platinum Full Synthetic oil. I'm not sure how good that oil really is though. My brother just ran some for a few thousand miles in his Subaru STi and he's going to send a sample out for testing at Blackstone Labs. When he does that, I'll try to post the results of his UOA here for reference. I still have a little bit of an uneven idle, definitely started after the oil change, but not severe. I have new plugs, ignition wires and fuel pressure regulator, so I know those things are not the cause. For my next oil change I'm going to use the Rotella 10W-30 which is available at my local NAPA store. Thanks for the help and recommendations.


07-13-09, 09:32 AM
I run the Pennzoil Platinum 5W-30 and a WIX 51522 in my STS and am quite satisfied. One quart in 3,500 - 4,000 miles, no leaks, quick and quiet. BUT that's in a roller cam engine. My Blackstone reports, for 3 years, show essentially no wear. I also run the same brand but 5W-20 in the truck 4.6 and all's well there, too. (The truck, at 64,000 miles, uses 1/2 quart in 6,500 miles !!)

For flat tappet or flat follower cams I'd stick with your Rotella or the 10-30 Long Life if you can find any. CHEVRON is also a heavy hitter in the marine and industrial lubricant area.

07-15-09, 04:06 PM
Some folks over on BITOG seem to recommend the Pennzoil Platinum Full Synthetic oil. I'm not sure how good that oil really is though.
I have gotten outstanding UOA's in my Fords with it. Better UOA's than I had with Mobil 1 and it costs less.
The Wally-Mart near me has been carrying a lot of Rotella 10w-30 lately.
Some high-mileage oils have more ZDDP than regular oils. Check the MSDS to be sure.

07-31-09, 12:32 AM
I tell all my customers to use Rotella 15w40.

07-31-09, 08:22 PM
I've been running the 15W-40 Rotella for a few thousand miles in one of my Devilles. I just put 10W-30 Rotella (found at NAPA) in my second Northstar vehicle. They both smoothed out the engine significantly and I like them both very much. The 10W-30 seems to have less drag on the engine (as expected). So this is my new favorite! Feels great in the car, has excellent specs, is considered HDEO and has the ZDDP these cars need. Case closed for me.


07-31-09, 09:08 PM
Looks like I'll be paying Napa a visit. Thanks.

07-31-09, 10:29 PM
Hi Ranger -

Just a quick FYI, there is a local chain with about 6 auto supply stores local to where I live and I noticed they carried Rotella products but not the 10W-30. I asked if it would be possible to order some up and they said "Yes", they typically place orders 1x/month and could add a special request for a particular Shell product without any issues . . . Just thought I'd share that in the event that your local NAPA does not carry the 10W-30.

Good luck!


08-01-09, 10:22 AM
Thanks Andrew. I might check with Walmart on that as I am sure it would probably be cheaper than Napa.

08-01-09, 02:08 PM
Great idea. I've seen some posts that specific Wal-Marts to carry the 10W-30. Unfortunately, my local Wal-Mart does not :crying: . . . Also, my recollection is that the prices at NAPA were not outragous. Good luck!