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Jenniflow · 08-28-2016, 10:30 AM

Hey Folks,
I apologize for asking this for what may be the 30th time, but I did a few searches and did not find the answer. Can someone direct me to the discussion of which weight oil to use in a Chevy 454 with 80,000 miles on it? Or just answer the questions below, please?

The last garage that worked on the coach used 10-30, so I'm asking three questions:

1) Is that bad? If so, why?
2) what should I use?
3) can I mix these particular oils as I top it up?

Or maybe just direct me to a thread where this is hashed out?

Thanks again!
Jenniflow

ALANSD · 08-28-2016, 10:45 AM

nothing wrong with 10-30. I would use Valvoline High mileage, but that is just a personal thing. 10-40 in the warm weather and 10-30 in the cooler.
More important is changing it regularly and an occasional bottle of Sea Foam or other good oil treatment works well too. When i had my 280 with the 454 it had 100,000+ miles and performed just fine.

bkahler · 08-28-2016, 10:54 AM

Jenni,

For years and years GM recommended 10w30 oil for the 454. I've always used 10w30 in my 454 powered vehicles and never had issues.

YMMV

Brad

Jenniflow · 08-28-2016, 11:24 AM

Hi, yes, that's great to hear, thanks. At least that wasn't one of my mistakes.

On the other hand, we are headed into the desert where the highs will be low 90s if we're lucky. Could easily get to be 100.

1) If I started adding 10-40 would that be bad? I burn about 1 quart every 300-400 miles

2) And if I also use the oil treatment? Or is that gilding the lily and/or causing precipitates that I don't want precipitating?

3) And reading the ongoing 454 thread (http://www.airforums.com/forums/f159...mh-151534.html), My engine is running at 220, which suggests that if I were smart I'd do a radiator backflush like Bkahler and Grosspoluter did. I wonder if I were to use Redlines (in the cooling system, right?) That would help keep the engine on an even keel until I have time to do that? Or do I have to do the flush first?

Jenniflow

68 TWind · 08-28-2016, 11:40 AM

The 10W-40 might help reduce the consumption a little. If your oil consumption gets worse you might try Lucas Oil Treatment. I have had excellent results reducing oil consumption in several very high milage vehicles and in lawn equipment engines. My son had a V-6 4-Runner that was using a quart every 200 miles. With Lucas he would go several thousand. I don't want to start an argument on oil additives. Most all the oils from the majors now have very good additive packages and are fine. But, for older high milage engines that were using a lot of oil, it worked for me in reducing excessive oil consumption.

Jenniflow · 08-28-2016, 10:39 PM

Thanks 68 TWind, I'm going to switch to 10-40 and look into the Lucas Oil tx. Sounds promising.

slowmover · 08-29-2016, 04:36 AM

Lucas not so great. I'd today use Rotella T6 5W-40. Read over on Bob Is The Oil Guy for what to use with gasser big blocks for more depth.

TomKirk · 08-29-2016, 11:57 AM

10W-30 is what your motor had in it from the factory.

As your big block ages, graduate to 10W-40; and then as big block ages further, graduate to 20W-50.

As your big block ages, you must be the judge on what weight oil to use. Always use premium oil.

Here's the deal: Once you graduate to a heavier oil, you must never go back to that lighter oil. Once done, it's done.

Q: Before this last oil change, what weight oil did you have in your big block??

Above all, with the exception of operating in really frigid climate, you must never graduate down to 5W-30 - or a 5W anything.

Tom

Grosspoluter · 08-29-2016, 03:07 PM

I would NEVER use 10/40 it breaks down way to quickly
I used 10/40 in a ford 390 v8 and when the weather would get hot and the engine would get warm I could see a noticeable drop in oil pressure.
Now oil pressure is going to drop when the oil gets warm.
I had a "friend of a friend" who used to race cars at the Rockford Speedway and he said 10/40 motor oil is garbage.
I believe him, he told me to use 10/30 and oil pressure Would drop a bit when things were good and hot.
it never went down as low as it did with the 10/40 in it
When I bought my 345 the previous owner used 5/30 I thought that was WAY to thin but I didn't want to change the engines oil diet
That was a BIG mistake! See some of my recent posts
I would stick with the 10/30 in your case
Me I went to Mobil 15/50 because I beleieve I did some damage when my 454 overheated because of a failed fan belt.

ROBERT CROSS · 08-29-2016, 03:45 PM

I'm an Amsoil retailer.....I'm biased.

10-30 Synthetic....no need for additives.

I ran Pennzoil & Mobil One 10-30 in our 95' 454 Burb for 170k with no problems.(pre Amsoil sales)

Regular O/F changes are more important than Brands, any top tier brand is fine,(did I really say that).

Bob

Jenniflow · 08-29-2016, 04:07 PM

Well. That's interesting. When I'm reunited with the vehicle I'll check to see what was in there when I bought her and see what I can learn.

SpletKay06 · 08-29-2016, 05:20 PM

The best oil for your application is Amsoils 10W-30 z-rod oil. As long as your oil pressure is in spec there's no reason to use a heavier weight oil.

Boxite · 08-29-2016, 05:41 PM

Jenni, ..... if you want to start an argument bigger than current politics.... go to WalMart to the motor oil aisle and wait for Bubbas to show up and pick up their favorite oil...then say to them... Ya know...that's not the best oil to use...
Then stand back and watch the sparks and fists fly.

I suggest you use what the mfr'r of your vehicle recommends. The owner manual will stipulate that. 10W30 is a common recommendation for all climates and service.
GM was expecially adamant on some of their vehicles, cancelling warranty coverages in some vehicles for using 10W40 oils, so be careful even if you are out of warranty. (Why do what the mfr'r specifically warns against? They should know what their product needs.)

Next, ... take folks advice about which BRAND to use with a grain of salt. A BIG grain.
Back in the Pre-70's the best oil was "Pennsylvania-Grade crude" based oils. This was because the oil from that state was known for a molecular structure resistant to break-down.

Modern chemistry has changed all that, coupled with the fact that these days most major brands are produced at the same refinery and then bottled into whatever color/brand is being specified.... but the fact is that these days crude oil comes from W. Texas, and Bahrain, and Saudi, and Argentina, and...the list goes on... it is shipped via pipeline and ocean tanker to Pasadena, TX where it goes into the same tank at the Shell refinery and is all produced to the same EPA-regulated standard, then labelled according to brand...and PRICED according to brand... but if it's got that little "starburst" API/ILSAC seal on the bottle...it ALL meets the warranty and performance standards regardless of which brand/price.
You are simply wasting your money if you pay for high priced oil because of some brand-name. WalMart SuperTEch is every bit as good as Quaker State, or BP or whatever....but you'll save a bunch of money over the years, especially if you have an oil-burner like you seem to state.

(BTW, you should find out why that car burns so much oil in so short miles. There's something wrong, and it may be a very simple matter like a dirty PVC valve..costing almost $3 to fix.)

Avoid all SNAKE OILS like Lucas, or STP or any other "additives". Here's why:
The refinery was very careful to put the right amount of oil versus additives in their recipie to meet that API/ILSAC standard. If you add more snakeoil additive you will upset that balance and do more harm than good, and drain your wallet more as well. DON'T. (IF snake oil additives were good for your car then the mfr'r would have specified them as necessary to maintain their warranty. They didn't, in fact, they probably warned against it. So YOU don't.)

Change your oil and oil filter regularly (3K miles is often recommended but I think that's excessive, I use 4K) ...but again, your owner manual will specify.
Change your engine AIR filter at least annually, because your engine sucks 7 times more air than gasoline and that's where most of your engine is vulnerable. (I change mine every 12K miles.)

Hope this helps.
George (Retired auto, aircraft mechanic and maintenance instructor)

BigButtUgly · 08-29-2016, 06:52 PM

I did a complete rebuild of a 454 with racing parts in a 74 Suburban and am a firm believer anytime you go over 400 HP or 450 Ft Lbs torque or any engine which is turbocharged, use full synthetic oil. Is the radiator original and do you have an auxiliary oil cooler? If no to both, go with ROYAL PURPLE -NON CALIFORNIA - EXTREME PERFORMANCE & RACING MOTOR OIL. It's a full synthetic with superlative credentials. Expensive @ $17.99 per quart. I'd run 20 W 50. Make sure oil pressure at idol stays above 20 psi and down the road at over 50 psi. You will not shell your engine with a failed oil pump, water pump, serpentine belt, blown hose. split radiator if you act quickly. My 454 ran 25 miles with a bone dry radiator (blown serpentine) and no engine damage. I Run ROYAL PURPLE in my Cadillac Escalade EXT

Jenniflow · 08-29-2016, 09:59 PM

Well, there are certainly some differing opinions here. I do think the argument about manufacturers' recommendations make sense but I also wonder about the difference between the condition of the vehicle they're selling and the same vehicle 80k miles down the road and how that might influence oil choices later.

My impression of what was said above about never going back to a lighter weight oil was that the change of oil actually changes the seals? Or something about the set-up so that you keep having to fill some gaps that have been created? Is that a well known thing? A hunch? An inference?

It makes sense to me that an older engine has somewhat different characteristics.

I don't mind adding extra 10-30 but I'd like to know a lot more about what's actually going on in this engine and cooling system. I just don't have time to find out right now.

i also have the cost/benefits to consider. I have to pay someone to do this work. I'm not a hobbyist.

Jenniflow

Smartstream · 08-29-2016, 10:21 PM

Give these guys a call. http://www.blackstone-labs.com/what-is-oil-analysis.php They actually test oil and can tell you exactly what's in it. Send them a sample of your oil and for less than $20 they will tell you a lot about the condition of your engine, fuel in oil, antifreeze in oil and wear patterns by the amount of bearing, cast iron and other metals in your oil. Several samples over many miles will give you a very accurate account of the condition of your engine. They are a small outfit and are very good about explaining things over the phone.

Jenniflow · 08-29-2016, 11:11 PM

Great idea, Dan, I love it. I'll do that. Thanks.

Jenniflow

Grosspoluter · 08-30-2016, 04:31 PM

I agree with EVERYTHING Boxite had to say
Like Smartsteram I did use blackstone labs and I'll be using them again
I admit I use Amzoil full synthetic in my 2001 Honba C-RV and my 2006 Mazda Miata
I like word of mouth and I use the Amzoil in the two daily drivers, I personally beleieve synthetics are a better (but more expensive) alternative
( that's just my opinion you can take it for what it's worth)
I be decided to go with the Mobil oil because it seems to be the popular choice here and on other RV forums
One more thing... I learned here is that the temperature sending unit on the 454 is on the head it (the tempature) is always hotter on the head I have two gauges the original one on the head and another on the upper radiator hose they read about 15° - 20° difference head is Always hotter!

Jenniflow · 08-30-2016, 04:44 PM

Very interesting, Grosspolluter, about the temps!

Jenniflow · 09-09-2016, 12:48 PM

For the time being, I've decided to stick with the 10-30. We're not burning all that much, maybe a cup every 5-6 hours of driving. If it gets much worse, I'll revisit the question.

And the whole thing seems to be running a lot better since we got the new transmission and are actually, Heavens!, driving it.

more reasons to use the Ole Gal! She gets lonely sitting in storage.