Oil Confusion - Older 73-87 Chevy 454 Engines

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I am so confused I don't know what to do anymore. I have spent hours and hours pouring over research, forums and documentation. I have several 80's Chevy full size trucks with 454 big block engines. They are all original and haven't been changed to modern roller cams. The more I read about new engine oils the more I am concerned about what to use. These trucks do not have catalytic converters, they never did from the factory as they were exempt since they are 9900 gvw 1 ton trucks. I have been running Rotella T5 10w/30 in them since they all sit a lot and don't get run for weeks or months at a time. I want to stay around a 10/30 weight as that seems to give me good oil pressure and no oil consumption. I am not sure if synthetic is doing these engines any favors, I don't have any leaks. I also have been reading the Rotella T5 still has the ZDDP I need but again unsure about that. Other folks say to use VR1 racing oil and still others say just regular Valvoline 10/30 or even 5/30 is just fine. I am so confused and want to make sure I am giving these engines the longest life possible. A big block rebuild costs about 4-5k nowadays and I hate pulling engines. Any suggestions?
 
I have a 77 GMC Jimmy with a 400 small block. I Run Mobil 1 high mileage 10w 30 with a Fram Ultra filter and change it out once a year.
 
Don't get too worried about oil, it really isn't THAT big of a deal.

Rotella T5 10w30 sounds fine to me, keep on with that.
 
If what you're doing is working, don't change it. Since your BBC's are well-broken-in and have the stock mild camshafts without radical lift, high lift rate, or 600 lb valve springs, you'd really be just fine with a modern passenger car oil with around 800 PPM of ZDDP. There's really no need for 1500 PPM ZDDP levels from racing oils unless you're breaking in a new cam/lifter set, or have a much more radical flat-tappet cam than a factory 80s BBC. Rotella's formulation has been changing to keep up with new regulations, but as far as I know, the 5w40 T6 still has around 1000 PPM of ZDDP. They removed the "official" gasoline engine ratings from it, but since there's no magical set of ingredients that gas engines just have to have which diesels don't, don't worry about it. They removed the gas engine approvals because to meet more modern gas engine approvals, it would *lower* some additive levels compared to what they can use with a diesel-only set of approvals. I personally am continuing to use RT6 5w40 in my 60's Chrysler 440 big-blocks, which have slightly more aggressive cams than your 80s BBCs use.
 
The BBC doesn't need a syn oil.The differences between syn oil and conventional base stocks these days are somewhat minimal. Compare the additive packages. Syn is a good idea for below freezing starts.
 
As stated above, the OEM cams, lifters and valve springs will all live long and happy lives with 800 PPM of ZDDP, once broken in. For you, that happened long ago. Plenty of oil out there with that.

Rotella T5 is a fine choice. Don't worry about HDEO w/o gas engine API rating. They did not change the formula that much, if any. They just dropped the rating because of API current requirements.

I would not run a straight synthetic oil in these older engines. No need to, and there is the chance of drain-off if they sit for long periods. That means there is maybe less film (not no film) on cold start. These engines like a nice thick residual oil film to keep wear to a minimum until pumped and sling oil get going. Your current oil is fine for that
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I've built a fair share of BBC's and they love good old dino oil. The thing is to change it when needed and run a decent filter. Since these are 9,000 GVW trucks, you have lots of room. I'd run the longer 2 qt filter for a bit more capacity. Any NAPA store can cross reference the filter.

You're in Penn, so it gets cold there. The bigger filter will have more media area. So when it's pumping cold thick'ish oil, it will have an easier time w/o the internal by-pass opening, and that's a good thing.

I'd do Napa Gold filters and once a year changes and be happy
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I think you are totally fine with what you are doing. I run 10w-40 in my older motors but really almost anything is fine and will work for you. Don't lose sleep over it Brother.
 
I've owned an '85 C3500, 454/TH400 with 4.10 gears, for 10 years and 50,000 miles (77K to its current 128K) and use Schaeffer's 7000 10w30, a dual-rated, SN syn blend. If your BBC's have close to stock cams in them have no fear of "low" ZDDP - your syn blend Rotella 10/30 is a good choice.

If anything, questions about "what oil" will get more variety of answers with these old engines than any new 0w20-spec Pilot or Chevy 5.3. My opinion, regarding pre-port-injected Chevy V8's and inline 6's, is that 5w30 is only for fresh, tight engines that don't see extensive truck-type use. 10w30 or '40 is good unless it's run long enough, or is of a type (conventional) that's going to shear down - hence why I use Schaeffer's that never shows any oil pressure drop even up to last year's 6,400 mile OCI. 5w40 sets about the same as 10/30, and 15w40 isn't necessary unless you're working it real hard most of the time, particularly in a warmer climate, or the engine has some wear that needs a little thicker oil to keep it quiet and oil pressure up. Anything thicker than 15w40 is only appropriate for stuff like racing engines, with the appropriate knowledge to know what to use and why, or as a last resort to get a few more miles out of an engine that's, basically, completely worn out.

The "10w30 is too thin" crowd, I think, is largely those that haven't moved past the days when all but the finest oils sheared substantially in even these engines that aren't overly hard on oil. Today's oil chemistry is light years ahead of what our engines survived hundreds of thousands of miles on back in their day and the viscosity of a 10w30 HDMO will take thousands of miles longer to shear down to the same point that a 1980's 10/30 would have in 3K. Synthetic, "low" zinc, 30 or 40 weight - have no fear.
 
Relax! Your Rotella T5 10w/30 is perfect. It is a duel rated oil and is a better quality oil then the best oil that was available when those engines were new. The fact that they don't leak and don't use oil is a real plus these days. They will out live the chassis which will out live you.
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Thanks for all of the feedback, I feel good about my choice of Rotella T5 10/30. I like the synthetic blend for fast lubrication that synthetic offers on cold starts and also the long service life I can get out of it. I only change the oil once a year because of the low miles, about 1000 or less, I put on per year.
 
Originally Posted By: Alex_V
I've owned an '85 C3500, 454/TH400 with 4.10 gears, for 10 years and 50,000 miles (77K to its current 128K) and use Schaeffer's 7000 10w30, a dual-rated, SN syn blend. If your BBC's have close to stock cams in them have no fear of "low" ZDDP - your syn blend Rotella 10/30 is a good choice.

If anything, questions about "what oil" will get more variety of answers with these old engines than any new 0w20-spec Pilot or Chevy 5.3. My opinion, regarding pre-port-injected Chevy V8's and inline 6's, is that 5w30 is only for fresh, tight engines that don't see extensive truck-type use. 10w30 or '40 is good unless it's run long enough, or is of a type (conventional) that's going to shear down - hence why I use Schaeffer's that never shows any oil pressure drop even up to last year's 6,400 mile OCI. 5w40 sets about the same as 10/30, and 15w40 isn't necessary unless you're working it real hard most of the time, particularly in a warmer climate, or the engine has some wear that needs a little thicker oil to keep it quiet and oil pressure up. Anything thicker than 15w40 is only appropriate for stuff like racing engines, with the appropriate knowledge to know what to use and why, or as a last resort to get a few more miles out of an engine that's, basically, completely worn out.

The "10w30 is too thin" crowd, I think, is largely those that haven't moved past the days when all but the finest oils sheared substantially in even these engines that aren't overly hard on oil. Today's oil chemistry is light years ahead of what our engines survived hundreds of thousands of miles on back in their day and the viscosity of a 10w30 HDMO will take thousands of miles longer to shear down to the same point that a 1980's 10/30 would have in 3K. Synthetic, "low" zinc, 30 or 40 weight - have no fear.


It's not about shear, it's about BBCs being sort of unhappy engines with sustained high rpm. In the marine industry, the idea of loading up a 30 weight into a BBC is almost hilarious. The amount of metal they shed in a short period of time is actually kind of astonishing.

Universal average for 50 hour OCI is about 50-70 ppm depending on the lab. We've gotten that down to the 20's on 100+ hour OCI's using Schaeffer and VR1 20w50.

Best UOA we got using a sub-50 oil was using RT6, delivering high 40s on iron over a 100 hour OCI.

Volvo Penta had the bright idea to use SAE 30 synthetix diesel oil in big blocks (much stouter than any passenger 10-30), and had engine failures inside of the 2-year warranty period. They then modified the spec to 15-40 diesel oil. We have seen a lot of VP 7.4 and 8.1 engines with awful compression 300-400 hours into service with documentation of regular service intervals on VP SAE 30.

Mind you, all of the above concerns roller cam BBCS with broomstick truck cams.

Point is, if you're giving a BBC average duty, a 30 is fine. Millions of trucks did it for tons of miles. If you're beating on a BBC and want it to last, go thicker or you might pay the price.

Where shear is concerned, these engines will eat all but the best oils for breakfast under sustained high rpm.
 
If you want more zinc go with a 40 grade, they are allowed more. I'd run a 10 or 15-40. You're not running the oil much between changes so really almost any oil will do the job. I'd consider a 2 year oci unless you start driving them more.
 
I called shell regarding ZDDP and the rotella there was only one that had the recommend rating for a replacement of the quaker state defy I was using. It was 15w 40 and I did not want to run that. After reading this thread, I will look for a T5 10W30. I think a call to shell and one of their technicians will answer your questions regarding rotella.
 
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I called shell and was emailed the following with a technical document. The document did not state ZDDP content.

"Shell Rotella T5 10W-30 Motor Oil has 1200 ppm of zinc."

What do you think?
 
Originally Posted By: rdc0000
I called shell regarding ZDDP and the rotella there was only one that had the recommend rating for a replacement of the quaker state defy I was using. It was 15w 40 and I did not want to run that.


Why not 15W-40 ? Those old Chevy engines are loosely fitted iron. They need thick oil to fill in the gaps.
 
If they seem tight and quiet, they will be fine on 10W-30. If they are slow to build oil pressure and you can hear any noises, get to 15W-40 ASAP. If they rattle when warm, move to 20W50 VR-1, Chevron Supreme, or equal.

In a 9,000 GVW truck, you can drop the pan and swap in rod bearings in about 2~3 hours being careful. A little longer to roll in mains. If the journals are shiny and smooth, you get many more miles out of them.

Clean the pan well and epoxy a plate magnet into the bottom. It'll trap loose iron and steel and you'll live even longer
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I build mine as "droolers" with a groove in the base boss on the distributor shaft to over oil the cam gear, 0.030" holes in the front lifter gallery plugs to squirt the cam chain, and slight grooved lifter bores to over lube the cam lobes (or run Howards direct Lube lifters).

That loose an oiling system need a HV pump to keep up. But works very well
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They all last many miles and run hard. They click and clack on cold start since there is little retained lube in the lifter galleries. But pressure comes up fast and they quiet right down. Then they start working or running hard (truck or car).

Last one out the door got plenty compliments from the new owner. Even under carb'd and with mild "truck" cam, it "has the nut" as he says
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Only part that is not stock BBC was cam stuff and the Weiand intake
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My cousin who bought my 1969 Camaro RS used Castrol GTX 20W-50. I see Castrol has an Edge Synthetic in 10W-60.
 
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The older version of this Castrol product was their RS 10W-60 (good race oil, when you need it that thick at op temp). It worked well in sump running close to 300*
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