What Oil to use 5.7 Engine

8

84EdH

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I bought an old stock, but new 5.7 longblock. This is a vortec engine with roller cam, cast iron high rise manifold and Edelbrock carb. I have used Royal Purple break in oil for the first 10-12 hours. I am ready to change oil and filter and start using a good synthetic.

Is there a consensus on what type of oil, straight, multi weight, etc.

Help appreciated!
 
H

HT32BSX115

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Re: What Oil to use 5.7 Engine

84EdH said:
I bought an old stock, but new 5.7 longblock. This is a vortec engine with roller cam, cast iron high rise manifold and Edelbrock carb. I have used Royal Purple break in oil for the first 10-12 hours. I am ready to change oil and filter and start using a good synthetic.

Is there a consensus on what type of oil, straight, multi weight, etc.

Help appreciated!
Click to expand...

Howdy,



You're going to get answers that include every type of oil made for internal combustion engines. (it's all been tried successfully)

Here's the official answer. If you don't want to use the oil suggested below. Use whatever you like.

What type of oil should I use? Can I use synthetic oil?

Engine Oil
For optimum engine performance and maximum protection, use the following oil:
ApplicationRecommended Oil
All MerCruiser enginesMercury MerCruiser Full-Synthetic Engine Oil, 20W-40, NMMC FC-W rated
IMPORTANT: Lubrication requirements for catalyzed engines differ from the requirements for non-catalyzed engines. Some marine-grade lubricants contain high levels of phosphorus, which can damage the catalyst system on MerCruiser engines. Although these high-phosphorus lubricants may allow acceptable engine performance, exposure over time will damage the catalyst. Catalysts damaged by lubricants containing high levels of phosphorus may not be covered by the MerCruiser Limited Warranty.
If Mercury MerCruiser Full-Synthetic, 20W-40 oils is unavailable, use the following lubricants, listed in order of recommendation. If you are servicing a catalyst engine, use these for short periods of time only.

  1. Mercury/Quicksilver 25W-40 Synthetic Blend, NMMA FC-W-rated 4-cycle MerCruiser oil
  2. Mercury/Quicksilver 25W-40, NMMA FC-W-rated 4-cycle MerCruiser oil
  3. Other recognized brands of NMMA FC-W-rated 4-cycle oils
  4. A good-grade, straight-weight detergent automotive oil according to the last row of the operating chart below.
NOTE: We do not recommend non-detergent oils, multi-viscosity oils (other than as specified), non-FC-W-rated synthetic oils, low-quality oils, or oils that contain solid additives.
oil%20chart.gif
This crankcase oil recommendation supersedes all previously printed crankcase oil recommendations for MerCruiser gasoline engines. The reason for this change is to include the newer engine oils that are now available in the recommendation.
Older Operation, Maintenance & Warranty manuals, Service manuals and other publications that are not regularly updated will not be revised to show this latest engine oil recommendation. Current Operation, Maintenance & Warranty manuals, Service manuals and other service publications that receive regular updates will receive this revised recommendation the next time they are updated.
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Cheers,



Rick
 
alldodge

alldodge

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Re: What Oil to use 5.7 Engine

I have a 454 in my shop with a spun bearing and it has used Merc 25W-40 Syn blend, and Merc filters. That being said I know of no late model engine which has failed to oil (jury still out on the 454). I "believe" that Syn oil is better then mineral oil so far as longevity and less wear. I also again have not seen an engine fail from oil. So with all this rambling I will say, use a good oil Syn or mineral and the engine will more then likely out last what you think the max hours could be.

I currently use straight 40W minerial oil in all my boat engines
 
8

84EdH

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Re: What Oil to use 5.7 Engine

I could not even find 20-40 wt syntheic at autozone. Just guessing merc price will be crazy
 
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84EdH

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Re: What Oil to use 5.7 Engine

thanks for the input all. Rick, I know many opinions on this kind of subject, I saw the Merc recco. but honestly, never thought of using 20-40 wt. I used to use straight 30wt in my marine engines years ago. 40wt was for the engines were high miles/hours. I will check the price of merc oil locally, I do use Mobil 1 in my car.
 
H

HT32BSX115

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Re: What Oil to use 5.7 Engine

84EdH said:
thanks for the input all. Rick, I know many opinions on this kind of subject, I saw the Merc recco. but honestly, never thought of using 20-40 wt. I used to use straight 30wt in my marine engines years ago. 40wt was for the engines were high miles/hours. I will check the price of merc oil locally, I do use Mobil 1 in my car.
Click to expand...

You can do a search here on other marine, auto, truck, motorcycle, leaf blower, law mower, tractor etc etc etc sites.

You'll get a LOT of opinions on what someone says their friend, uncle, dad, brother, sister, pet-mechanic, mercedes-mechanic, truck-mechanic, marine mechanic, army mechanic, USAF mechanic, leaf-blower mechanic, etc etc etc etc until you're blue in the face!


Bottom line, just use what the manufacturer suggests. obviously it doesn't have to be Merc 20W-40. Just about ANY SAE 30 or 40 will do. many people use 15W-40 etc. I use xxx oil and have never had a problem.:faint2:

I would suggest NOT using any brand of 10W-40 (unless it's a synthetic) because of the excessive viscosity improvers. No one has been able to prove that any brand of oil caused damage to any engine and no one can prove that any oil "caused" a spun bearing. Spun bearings happen all the time with all types of oil.

Ask on any forum and you'll get as many answers as as you get answers..................
 
achris

achris

More fish than mountain goat
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Re: What Oil to use 5.7 Engine

Oh, I might as well, as everybody else has....

I have a V8 turbo diesel tow vehicle. I had a 4.3LX. I wanted to run the same oil in both engines... So, was it to be 'petrol engine' oil in the diesel, or 'diesel engine 'oil in the boat?

I did a LOT of reading and research... My conclusion... (Just putting it out there, not saying you should do this....) My conclusion was that the diesel engine oil should have better shear qualities and is designed to operate under harder working conditions than petrol engine oil.... So, the 'diesel engine' oil gets used in the boat....

I buy in 20 litre drums, 15W-40.... Was using BP C6 Global (till they stopped making it :confused: :mad:), then used Castrol something, now using Mobil Delvac.

Been using those since about 2001, that engine (4.3LX, 1200 hours) is now in a friends' boat, still going strong. My current engine (4.3MPI) has 350 hours and I look inside the crankcase regularly, :facepalm: and it looks as good as the day it came out the factory.... The Landcruiser (GM 6.5l V8 Turbo :D) still good....

0.02c

Chris......
 
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alldodge

alldodge

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Re: What Oil to use 5.7 Engine

HT32BSX115 said:
No one has been able to prove that any brand of oil caused damage to any engine and no one can prove that any oil "caused" a spun bearing. Spun bearings happen all the time with all types of oil.
Click to expand...

Totally agree, still trying to figure out what caused the failure with only 200 hours, so it won't happen again. A third engine would be a real bummer
 
achris

achris

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Re: What Oil to use 5.7 Engine

AllDodge said:
Totally agree, still trying to figure out what caused the failure with only 200 hours, so it won't happen again. A third engine would be a real bummer
Click to expand...

Agree...

I've seen bearing shells out of the box with that little locating tab not pushed out. Put one of those in and the other shell is doing all the work to stop the pair spinning... Maybe??

Chris.....
 
8

84EdH

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Re: What Oil to use 5.7 Engine

So if one were to use Delvac do normal gasoline engine oil filters work with diesel oil?
 
achris

achris

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Re: What Oil to use 5.7 Engine

O goodie, a filter thread in an oil thread.....

:popcorn:

You can use any filter you like.... I've used OEM, Ryco, Baldwin, Fram, Wix, Cooper, Fleetguard... All basically the same, they trap crap in the oil and let oil passed... (I hope ;))
 
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Scott Danforth

Scott Danforth

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Re: What Oil to use 5.7 Engine

since there are three (yes that is 3) plants in the fricking world that make oil filters. use one, it will filter oil.

Chris, I too run 15W40 Diesel oil (currently running Rotela T) in most everything the wife and I own. especially anything with a flat tappet. and I mean everything from the boat, the Audi, to the Blazer to the riding lawn mower to the blowers to the weed wackers. will soon be running it in her PT cruiser. I have run every synthetic and dino oil, and everything in between. The boat gets changed once per year (about 100 hours), the car gets changed every 3 months (about 10,000 miles). in case your wondering, I usually sell my vehicles with between 250 and 300k on the clock. everything is run hard.

to the OP. since your running a roller cam, if you have roller rockers, you could even run 5w20, or even straight 10 weight. since you did the break in with royal purple. why not continue with RP? I myself am an Amsoil fan. in reality, to bashtardize a line from Bond-o Any Oil is better than no oil. So, in summary use what you want. IT WILL ALL WORK.

ok, now pass the popcorn.
 
achris

achris

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Re: What Oil to use 5.7 Engine

HT32BSX115 said:
Yeah. And Mercruiser engines are better than Volvo engines!:eek:
Click to expand...

Yeah, well... They are..... :argue:

Here's the bit I like.... Volvo spares (for exactly the same engine) are twice the price of the Merc spares... (That's what it is in Australia... :facepalm:)
 
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Lou C

Lou C

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Re: What Oil to use 5.7 Engine

I think its interesting to note not only what they do recommend, but what they did NOT recommend. As in, most have not recommended a 10w/30/40 or a 5w anything. But over the years, Merc OMC and Volvo have recommended straight 30, 40, 20w/50 (Volvo at one time) and Syn 30 (Volvo also) and now Merc with their own 25/40 in regular, semi syn and syn flavors. Volvo changed from straight 30 syn, to a syn 10w40 oddly. I do recall also that Crusader or PCM recommended the diesel/gas rated 15w/40.
My thought is, if you use what the Manufacturer considers good enough to keep the warrantee in effect you can't go too far wrong. I'd love to see good (and I mean GOOD) independent tests of these oils in marine engines (ie the ones that Merc and Volvo recommend vs, the 15w/40 diesel/gas alternative). It would be nice to know if one is better or if there is really no difference......

At the end of the day, a good test is, what is your hot slow idle oil pressure? Mine using straight 30, 40 and more recently the Merc 25/40 has always been at least 20 psi at slow hot idle. 40-60 at running speeds. So maybe there really is not much difference......
 
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