Someone else should e-mail Shell and ask the same question (zinc ppm in rotella in general, not a specific weight/type) and see if they get the same answer I got
12 bux for the Rotella and about $2.50 for the STP with ZDDP in it is good enough for me. Picked it up yesterday-wont lose any sleep over it...-rick
I see a lot of back and forth information on this subject, not only on this thread but everytime the subject of zinc in oil comes up, so maybe this will help clear up some of the questions about Rotella. At my job we are a Rotella distributor and today I called my contact who put me in touch with one of the head chemists. Here is what he told me: 1) NO Rotella oil has enough zinc in it today to support a flat tappet cam motor. It used to, but they pulled it out to meet current regulations. He said "No matter what anyone tells you, we do not put enough zinc in there to protect the older, flat tappet motors." 2) He said the reason is that there isn't a big enough market these days for them to invest money in making a separate product just for the older motors. 3) He suggests the VERY BEST way to protect one of these motors is to buy their 15-40 Triple Protection oil and then add Lucas Zinc Additive. I told him that is what I have always done and he said that is why I have never had a cam failure. I told him I thought the diesel rated oils would have enough in there to work and he said "Not any more !" So, I hope this helps all of you with older motors out. I am building a flat tappet cam 350 Chevy right now and it will get my usual Rotella and Lucas cocktail, especially now that I know the straight scoop from someone who knows. Don
Don's Hot Rod - Thanks for sharing correct current information. For correct Zinc content Lucas Hot Rod & Classic Car Motor Oil is available too.
Very good info straight from the source, confirming what we talked about. So, for low spring pressure flat tappet cam engines like a stock or mild 216/235/261, the OP asked about, the current Rotella T formulation has more than required amount of ZDDP/zinc/phosporus of 1100 ppm. Even off the shelf current motor oils with lower levels (700-800 ppm) are OK for these engines, especially with a properly broken in engine after 15K miles. That's the same level as was in the oil from the 1950s. Only for hotter motors with higher spring loads, you need to add ZDDP to bring the level up around 1200ppm. However watch out not to exceed 1400 ppm as it harms the cam over time. I have used Rotella T with the 2007 formulation (1200 ppm) since it was introduced in my 30+ year old 235 with stock cam. Never added more ZDDP. The newest formulation has only 100 ppm less and I still don't add ZDDP. For my 2008 rebuilt 261 with stock springs but higher lift cam, I have used Rotella T with no added ZDDP for the first 10K and then switched to standard off the shelf motor oil and bring the ZDDP level up to 1000 ppm to be on the safe side.
1) NO Rotella oil has enough zinc in it today to support a flat tappet cam motor. It used to, but they pulled it out to meet current regulations. He said "No matter what anyone tells you, we do not put enough zinc in there to protect the older, flat tappet motors." This mean's you must ADD zinc.
I'm in Don's camp, except I use VR1. I quit using She'll when they changed it. Just the fact that there is so much conflicting opinion should cause all of you concern. The most critical time is at break in, obviously. After that, you may get by with reduced zinc but why risk it?
At one time I'm sure the diesel oils were OK to use but as with the conventional motor oils the zddp ppm levels have been significantly reduced by government mandates over time.
Despite Don's information he got directly from the horses mouth (Rotella Chemist) I'm not surprised that some posters will argue the point on the amount of zinc in Rotella. BTW Valvoline VR-1 has 1400 PPM of zinc and 1300 PPM of Phosphorous.
Have a look here for lots of talk about oils: http://blog.speedtalk.com/2014/02/can-you-always-count-on-high-zinc-motor.html
what Don's connect said is just a repeat of what i said here days ago and in other threads here many moons ago. again aircooled guys have beat this topic to death for many years. Rotella used to be the go to. it was great oil at a reasonable price. when they reformulated i literally went around town buying up what i could of the old formula and had good stock for a coupla years. after that i switched to VR1 for a short while even though i wanted to use Brad Penn. Penn was just hard to get here and my local napa had vr1 and i got a decent price on it for a bit. now that Penn is available at a coupla local spots it's what goes in my flat tappet stuff....
I remember this was previously posted on the HAMB last year. Here is the complete extended blog from the same author with new update from 8 days ago.... http://540ratblog.wordpress.com/ According to this data, the new Rotella formulation has actually around 1400 ppm zinc hahaha Interesting how adding the popular ZDDPlus additive also lowers vital psi values, degrading the oil. I guess somebody has to pay the $20 or so that Blackstone oil labs requires for an independent oil analysis. So who's the hero putting us out of our misery and this puppy to rest? It sure ain't me and my low performance engines - Yawn. But all the best, going with anybody's advice without actual oil analysis data matching your application and actual use, if you want to be 100% sure.
My info (the first post) was straight from the source as well so who knows. Don't worry guys, I put the rotella 15/40 in the motor today so we'll know soon enough huh? On another but somewhat similar note, whats everyone's oil pressure at idle, once the motor's warmed up? Mine is directly in the middle of the first dot and the second dot (15 psi.?) and at speed it's between the middle and third (45 psi.?). Is that normal for the 235?
Also if it has not already been mentioned you can use Chevron Delo oil. For diesels has fairly high zinc content.
Oil pressure specs for a 1954 235 (stock block/head/rocker arms) : Normal oil pressure ... 45 PSI @ 1170-1200 Engine RPM and SAE 20 straight grade That's about 26 mph with stock 3.70 rear, stock tires and calibrated speedo. Source ... http://chevy.oldcarmanualproject.com/chevyresto/5436.htm Oil pressure at idle can be pretty low with an older engine, but still OK, as long as its up to spec at speed.
What is odd to me is that in the past we never had to worry about cam problems, and we bought whatever oil was on sale. Hell, I used to buy bulk oil at 10 cents a quart and I can't ever remember having a cam fail. Some people blame it on the metal today's cams are made out of, but, if anything, I would think we have gotten better in that regard in the past 50 years. I never even broke a cam in at 2000 rpms back then, I would put it in, fire up the motor, and sit there listening to the cammed up idle for a while. Now, we immediately get the rpms up and keep it there for a half hour, and we hold our breath, hoping we didn't wipe out a lobe or two. Very confusing , what has changed ? Don
Most of this started after some Chevys with really stiff springs wiped some cams. At the time, and since, there's been speculation as to weather it was a batch of bad cams from one big name, but unnamed, cam company, bad Chinese lifters, lack of zinc, or all of the above. Higher valve spring pressure, Chinese lifers have received scrutiny as has the zinc content. No definative answer yet.
The cars, engines, oil and emission requirements have changed ... and along with it ... available motor oils. About 10 years ago when a few reports of failed high-performance cams started to show up, on the fancy 'new' internet, it was predictable there would be Zinc/ZDDP additives available for vintage and classic cars, eventually. So today, we just have to do the math and guess work to suit our needs or simply trust experts that are on our side, unless you want to send an oil sample to your favorite oil analysis lab every time the formulation changes. Last change was around 2011, so we can expect the next one pretty soon...
How long does it usually take for the cam lobes to be shot? I drove around all day yestarday and I've been driving all day today and so far so good. My oil psi is at about 30 with the motor at 1200 rpm by the way
So I guess only time will tell. I'll keep posting on condition for a while and if the motor craps out on me I'll be sure to tell everyone.
Alright guys...it's been 10 days since I started using the Rotella T. Is it too early to call the zinc myth busted?
All you have to do to get your zinc answer is look up the MSDS sheet of the oil you want to know about. Here's the sheet on Rotella T: http://www.prairielandelectric.com/msds/inbookmsds/ROTELLAT.pdf
Way too early. Some have reported failures with up to 1,500 miles, though we don't know for sure if it was zinc involved or not. The only thing we know for sure is roller cams don't need zinc, & the OEMs got the oil companies to eliminate it to help the car companies reduce pollution numbers. Some aftermarket spring are 2-3 times higher spring pressure than stock engines from back in the day had & that might be the whole problem. There are certainly plenty of pre-roller cam cars on the road that are using SM & SN oil w/o problems.
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