What motor oil do you use?

[69L88clone]

Looking for recommendations as to the best motor oil to use in my big block. What do you guys use?
Thanks in advance.

 

[Tom73]

I use Moble 1 in my '73 454.

 

[bill81vette]

I use Castrol GTX 10w-30 in mine


bill.........

 

[Vettehead Mikey]

You'll get answers all over the clock on this one. It really doesn't make much difference what type you use for engine durability, just use the grade recommended in your owners manual and observe a reasonable change interval.

Synthetics have no advantage over dino except for the potential for longer change interval.

 

[Grizzly]

You'll get answers all over the clock on this one. It really doesn't make much difference what type you use for engine durability, just use the grade recommended in your owners manual and observe a reasonable change interval.

Synthetics have no advantage over dino except for the potential for longer change interval.

I beg to differ on that last point. As far as I am concerned the real advantage to synthetics is their resistance to heat breakdown. That's why I use it in everything right down to the lawn mowers. The vast majority of us change oil based on time, because we just don't drive them enought to do it based on milage.

For an engine that I hear has overheating problems, heat resistance may be the real issue.......................Griz

 

[gmjunkie]

I beg to differ on that last point. As far as I am concerned the real advantage to synthetics is their resistance to heat breakdown. That's why I use it in everything right down to the lawn mowers. The vast majority of us change oil based on time, because we just don't drive them enought to do it based on milage.

For an engine that I hear has overheating problems, heat resistance may be the real issue.......................Griz

I second THAT!!!!!!!!!!!!!!!!!!!!! ps.I use Castrol SynTec in my LS6 in my Haul'n Truck!!

 

[69L88clone]

I thought about using Mobil 1 with a supplement of ValvolineSynPower Oil Treatment. But I posted a question to the mobil1 techs about this & this is the reply I got:
Mobil does not recommend the use of any oil additives with Mobil motor
oils. Theses products are not licensed and alter the chemical balance
and formulation of the motor oil.

So, I'm still not sure what to use.
Jim

 

[Vettehead Mikey]

I beg to differ on that last point. As far as I am concerned the real advantage to synthetics is their resistance to heat breakdown.

Proof, please. I've heard that argument a thousand times and followed it up many times more in my professional career dating back to the late 1970s, but no one can ever come up with proof, just theory that's derived from marketing BS.

I oversee a fleet of approx. 1000 aircraft engines that are supposed to use synthetic oils- when we tear them down at overhaul we see no difference from one oil type to another.

Piston engines in our C3s and your lawn mower cannot run hot enough to take advantage of the thermal properties of synthetics. They seize long before the oil breaks down.

 

[Evolution1980]

Looking for recommendations as to the best motor oil to use in my big block. What do you guys use?
Thanks in advance.

Aww geeze, now you've gone and done it! :L
I already read all the responses above this. here's my 2 cents...

If your engine is original, or fixed with OEM parts, stick with regular 10W-30 in warmer climates. 5W-30 if you are in slightly colder climates.

If the engine is new, or has new piston sleeves, seals, and whatnot, use a Synthetic. But if you had non-synth oil in it all this time, just stick with that. But use a namebrand like Mobil-1 or Valvoline.

In the grand scheme of things, my opinion is that changing the oil at regular intervals and using a good oil filter such as K&N or Mobil-1 will benefit you the most. I don't know that any of us regular car people will ever see a greatly noticeable difference between using dino -vs- synth.

 

[Daryllawman]

I use Pennzoil 10-W-40 in all my cars and trucks. I use an AC Delco filter. I use Castrol 30 weight in my mowers..I have been using this for a long time now.....works for me.!

 

[Norseman]

Why would an engine seize if there is oil in it? Unless the oil has turned to sludge.
If you use Mobil one you will get better mileage. The C6 comes with Mobil 1 in it and the car reminds you when to change your oil. Yes the intervals are longer. It's a win win situation.
I've used Mobil 1 for years in my motorcycles and cars and have never had a problem. I've had mechanics tell me that cars that use Mobil 1 show almost zero engine wear no matter how many miles they have on them.

 

[JJS]

I use Mobil-1.

 

[srs244]

Why would an engine seize if there is oil in it? Unless the oil has turned to sludge.
If you use Mobil one you will get better mileage. The C6 comes with Mobil 1 in it and the car reminds you when to change your oil. Yes the intervals are longer. It's a win win situation.
I've used Mobil 1 for years in my motorcycles and cars and have never had a problem. I've had mechanics tell me that cars that use Mobil 1 show almost zero engine wear no matter how many miles they have on them.

if your assumptions above are correct, tell me why my 93 corvette came with mobil 1 and the requirement that it be changed at 3000 mile increments. i contend that it is all marketing BS and is determined by who is going to be paying. strange how now that maintenence is included in a lot of new cars, that the oil change intervals have gone from a recommended 3000 miles to 7500 or more. i will give some ground on the fact that technology from the 60's to now has improved, but give me a break if you want me to buy into that logic from pre maintenence included cars to the period when maintenence started to be included. technology didn't improve that much in the one year between buyer pays out of pocket to buyer pays through the nose, but cost is buried in the increased cost of the vehicle.

BTW, for what it's worth, i use castol GTX 20-50 in all of my cars from my 92 toyota paseo (37 miles to the gallon and my daily beater) to my 01 pt cruiser, to my 78 L48 pace car (12 miles to the gallon), to my 454 71 el camino (10 miles to the gallon, lol). trust me it's hot down here in the tropics in the summer, and i've never had a heat related engine failure yet, but that is all just one man's opinion.

 

[Grizzly]

if your assumptions above are correct, tell me why my 93 corvette came with mobil 1 and the requirement that it be changed at 3000 mile increments. i contend that it is all marketing BS and is determined by who is going to be paying. strange how now that maintenence is included in a lot of new cars, that the oil change intervals have gone from a recommended 3000 miles to 7500 or more. i will give some ground on the fact that technology from the 60's to now has improved, but give me a break if you want me to buy into that logic from pre maintenence included cars to the period when maintenence started to be included. technology didn't improve that much in the one year between buyer pays out of pocket to buyer pays through the nose, but cost is buried in the increased cost of the vehicle.

BTW, for what it's worth, i use castol GTX 20-50 in all of my cars from my 92 toyota paseo (37 miles to the gallon and my daily beater) to my 01 pt cruiser, to my 78 L48 pace car (12 miles to the gallon), to my 454 71 el camino (10 miles to the gallon, lol). trust me it's hot down here in the tropics in the summer, and i've never had a heat related engine failure yet, but that is all just one man's opinion.

Actually your oil requirements are less restrictive than those of us up here in Yankee Land. I can't imagine starting an engine at -10 degrees with 20-50 in the crankcase. With 5w-30 I have almost instaneous oil presssure at any temperature. At my home over the course of a year we will have 110-120 degree range of temperatures. You only have hot and hotter!

I think the real issue here is how much are you saving by not using the best? $10-$15 maybe. Doesn't make any sense. For my money, GM had the liability issue all worked out when they replaced an oil cooler with synthetic oil. They weren't going to replacing any engines from oil breakdown due to heat.

That's good enough for me..................

PS
My '92 has 7500 mile change intervals for the normal service. Did they cange it in '93?

 

[srs244]

Actually your oil requirements are less restrictive than those of us up here in Yankee Land. I can't imagine starting an engine at -10 degrees with 20-50 in the crankcase. With 5w-30 I have almost instaneous oil presssure at any temperature. At my home over the course of a year we will have 110-120 degree range of temperatures. You only have hot and hotter!

I think the real issue here is how much are you saving by not using the best? $10-$15 maybe. Doesn't make any sense. For my money, GM had the liability issue all worked out when they replaced an oil cooler with synthetic oil. They weren't going to replacing any engines from oil breakdown due to heat.

That's good enough for me..................

PS
My '92 has 7500 mile change intervals for the normal service. Did they cange it in '93?

grizz

the 93 called for 3000 and of course the dealer was pleased to see me at about $35.00/change. as for "using the best", i guess that depends on what you read, and who you believe (no disrespect intended, by the way). i've seen everything from "synthetics are the greatest thing since sliced bread" to "synthetics are ok, but under normal circumstances aren't needed or necessary". like they always say, opinions are like butt holes, we all have them, lol. please don't misunderstand my comments, i am not attempting to slam the product, just questioning the validity of it as a generalized statement. as i guess was pointed out in the second post in this thread, the questions would evoke a myriad of opinions.


btw, as you pointed out, we suffer from the hot and hotter syndrome down here, and many mechanics swear by straight weight oil (30 weight) for most applications. i don't buy it, but.........................just some more opinions, lol!!

 

[Grizzly]

grizz

the 93 called for 3000 and of course the dealer was pleased to see me at about $35.00/change. as for "using the best", i guess that depends on what you read, and who you believe (no disrespect intended, by the way). i've seen everything from "synthetics are the greatest thing since sliced bread" to "synthetics are ok, but under normal circumstances aren't needed or necessary". like they always say, opinions are like butt holes, we all have them, lol. please don't misunderstand my comments, i am not attempting to slam the product, just questioning the validity of it as a generalized statement. as i guess was pointed out in the second post in this thread, the questions would evoke a myriad of opinions.


btw, as you pointed out, we suffer from the hot and hotter syndrome down here, and many mechanics swear by straight weight oil (30 weight) for most applications. i don't buy it, but.........................just some more opinions, lol!!

I'm not offended at all by a differing opinion, I'd like to settle this in my own mind. I would appreciate additional comments from Vettehead Mikey. He obviously has more real experience than the rest of us, but I wonder if requirements of aircraft maintence are comparable to auto maintence. Hopefully they are a great deal stricter.

On the other hand if you are like me the oil in my collector cars seldom even gets that dark because I change oil by time rather than mileage.

Any more details Mikey?

 

[RedVetteMan]

I use Mobile1

 

[Vettehead Mikey]

Any more details Mikey?

It's best not to get me on my soapbox regarding certain issues, but here's something short. Nobody mention pertr*nix please.

Maintenance of aircraft engines is not much different than on any other machine- it's just very tightly controlled and regulated. A side benefit of all of this control is there's lots of data available for reliability and durability analysis. This was part of my job function for many years before I moved into the fleet management position where I am today.

First off, synthetic oils were NOT developed for a need for superior lubrication, but to deal with a quirk of turbine engines where the bearing compartments (not the bearing itself!) and drain passages get hot enough to 'coke' the oil and eventually plug up. Aside from that, regular dino oil would work just fine, and better in some circumstance (long term storage).

I became curious about the application of synthetic oils to piston engines in the late 70s when I joined the aviation community and soon found that the Mobil 1 that was sold for cars was a direct derivative of the same Mobil product developed for gas turbine engines. I was into high performance motorcycles at the time and was looking for a magic elixir.

After several years, no evidence surfaced that use of synthetic oils benefitted any bike engine I had a chance to work on or see. We're talking evidence that the oil would have avoided a failure or reduced it's impact, not 'it looked pretty when I took it apart' claims. 'Pretty' doesn't win races. Some of the bikes I worked on raced at Daytona during bike week, we're not talking Dunkin' Donut burnout contests.

The reliabilty trend analysis techniques which are part of my former job can be used on our Corvette engines-

-when do they fail
-what caused them to fail
-was it avoidable

If you study a large enough sample, you'll see trends. If you study Corvette engines (C1, C2,C3) you'll see that they typically need overhaul (not quite failed, but worn out) at around 125K miles and up. Earlier than that is usually due to abuse/race.

What's common with the mature failures (over 125K) and premature (under 125K) is that it's extemely rare to see a lubrication related event.

Overheating
Burnt valve
Cracked ring
Burnt piston
burnt/cracked head gasket
and a 1000 others

are not related to lubrication.

Possibly:
worn rings
worn bearings
worn cam chain

could be considered lubrication related, and in theory (and marketing BS)superior oils could maybe delay/prevent engine overhauls accordingly.

The problem is that the engine will need a shop visit anyway for other non-lubrication related causes as listed above, so what have you really gained by using synthetics? It's similar to paying extra to get a 1000 year guarantee on a muffler, there's no car left to hang the muffler on. :L

In spite of the above, I have challenged people to prove that an engine was less 'worn' in a manner that would be of direct benefit- i.e. avoided a failure or delayed it.

So far, after years of challenging- no serious takers, just more anecdotes...........

 

[srs244]

mikey
thanks for taking the time to provide your input. i for one found it very interesting.

steve

 

[Grizzly]

I too want to thank Mikey for taking the time to write all that........Griz