What oil would you use?

Daplumma · Post by **Daplumma** » October 7, 2011, 6:47 am

1965 250.390,yes I measured the stroke,holly double pumper with headers and a mild cam.Motor does not smoke exept when choked on start up.I dont know how many miles are on the motor.The truck gets driven 2 or 3 times a month for a twenty to thirty mile round trip ride to the dump and an occasional trek to the lumber yard.Almost never more than 30 miles.What weight-brand would you use?

slick4x4 · Post by **slick4x4** » October 7, 2011, 6:54 am

whats the oil pressure run ?
if its 25 psi 0r above at idle hot , i would go 10-30
lower than , probably run a 15-40

my

cooter · Post by **cooter** » October 7, 2011, 8:04 am

no synthetic if motor has higher milage, valvoline 15/40 if your driving in weather above freezing

charliemccraney · Post by **charliemccraney** » October 7, 2011, 8:32 am

cooter wrote:no synthetic if motor has higher milage

Why not?

Bill W · Post by **Bill W** » October 7, 2011, 10:55 am

nothin but Valvoline in my trucks

i tend to stay away from multi viscosity oils
30 weight in the winter 40 in the summer

Uncle Skip · Post by **Uncle Skip** » October 7, 2011, 11:30 am

I'm with BillW.
Single WT HD oil with a zinc additive. Synthetic oil is for new motors with very close tolerances. Our old motors with loose tolerances will burn it up in a hurry.
Don't forget the zinc additive or you could wipe out a bearing or cam lobe.
If it doesn't come in the oil like Shell Rotella-T, buy a bottle and use about half for every oil change. You don't need the entire bottle unless you're breaking in a new motor.
U@ss

charliemccraney · Post by **charliemccraney** » October 7, 2011, 12:07 pm

Uncle Skip wrote:Synthetic oil is for new motors with very close tolerances. Our old motors with loose tolerances will burn it up in a hurry.

So viscosity has nothing to do with it? Simply if it's synthetic, it can't be used in a "loose tolerance" engine?

I must have been very lucky, twice, or there is a lot of misinformation out there. I've run synthetic in my Y for several thousand miles in the past. It was fine and when I had it apart for upgrades, there was no indication of premature wear due to oil or anything else. I have the crankshaft on the shelf and it's still std/std and the same cam is currently in use in the engine and doing great.
I've run synthetic in my '88 Firebird since I bought it at 90,300 miles. I've put 53000 trouble free miles on it since. While the Firebird is give or take 24 years newer, the engine is in principle the exact same as the Y, other than the roller cam, which is stock.

So have I been extremely lucky or is there more to it? I think there is more to it.

Obsa · Post by **Obsa** » October 7, 2011, 1:04 pm

Charlie, IMHO opinion the latter is correct. Skip has without contest more knowledge about petroleum products than I but in you own experience you have seen different results.

Relating back to my own experience when I was still a productive member of society I had a saying when in a production enviroment about when parts were fubared Once is an anomaly, twice is a coincidence, three times denotes a pattern.

Bill W · Post by **Bill W** » October 7, 2011, 1:25 pm

there is only one reason (IMO) for not using synthetic oil in a old truck engine and that is COST. now if i had a brandy new rebuild on a engine after the brake-in peroid i would use a synthetic oil....
my wifes toyota tacoma only gets Moible 1 full synthetic since its first oil change.

Gatkpartz6179 · Post by **Gatkpartz6179** » October 7, 2011, 2:41 pm

southern style for older motors. 10w40 up north 20w 50 down south,conventional only,,change every 3000.brand is irrelevant save for your choice of already infused additives,all motor oil sold is astm/whatever approved for internal combustion engines.straight weight other than N D 30 is fine for tropical climates...simple,imo....Am stuck back in hospital agin 10/5 til? foot /leg infection and possible graft surgery,!@#$#@!

Uncle Skip · Post by **Uncle Skip** » October 7, 2011, 3:38 pm

Obsa, et al.
My reluctance for Synthetic is twofold in old engines.
One, in an old used engine, because its so slick, it seems to leak in places that don't normally leak. Ring and valve seal blow by also seem to be a problem when the motor is worn. And it does not have the protective zinc for bearings I talk about.
The other is the cost of the full synthetic.
I did change to Mobil 1 in my '94 300-6 that had 86,000 miles on it when I bought it and sold it at 217,000 with no problems. But two things here also; the '94 is what I call a new generation production of an old design and it had much better sealing surfaces, and two, it had been very well maintained and I used the Mobil 1 exclusively and never changed my routine. I also put the zinc additive in it at every oil change.
However, having said all that, I would be happy to use Mobi1 or the like in any new motor I built AFTER break in with Rotella-T and the zinc. Especially a flat tappet cam motor. I do use the additive with the synthetic oil just because.
My 03 Ranger and Mamma's Expedition get Mobil 1 exclusively and have since new.
But I still say, if you have an old motor that leaks or burns the slightest bit of oil, I'd stay with the old standare 30-40 wt.
Sorry for the confusion.
FYI, one of the EXXON engineers I know who worked in the Lubrication section at Baytown Refining told me how the mulit-viscosity oils actually work. He says there are microscopic rubber molecules suspended in the oil that expand when they get hot and increase the viscosity. Who knew?

charliemccraney · Post by **charliemccraney** » October 7, 2011, 4:22 pm

Uncle Skip wrote:
One, in an old used engine, because its so slick, it seems to leak in places that don't normally leak. Ring and valve seal blow by also seem to be a problem when the motor is worn.

RE the valve seals, that definitely seems true. Mine always makes a cloud when first started on hot summer days. One year I was tracking down an oil leak and switched to regular stuff while I was trying to locate it. I didn't want expensive stuff pretty well poring back out. With the regular stuff, the smoke cloud is less dense. Other than that there are no other leaks. It uses less than a quart between oil changes. The engine is clean for 143k miles. I can work on it without getting greasy. The person I got it from took good care of it. Too bad it met me

cooter · Post by **cooter** » October 7, 2011, 9:01 pm

as previosly stated, Synthetic leaks easier and burns easier so old engines (half worn out) will leak more and burn more

azjake · Post by **azjake** » October 7, 2011, 11:08 pm

Bill W wrote:nothin but Valvoline in my trucks

i tend to stay away from multi viscosity oils
30 weight in the winter 40 in the summer

Me too, Bill, since the mid '70s...

Jake

Daplumma · Post by **Daplumma** » October 8, 2011, 7:27 am

The oil presure is low on the truck,not sure if its the gauge or the motor.I use Rotilla in my diesal with good results.It gets below freezing here.Rotilla 15/40 sound OK?

BarnieTrk · Post by **BarnieTrk** » October 8, 2011, 8:21 am

Daplumma,
Yes, I'd suggest you run the 15W-40 diesel-grade motor oil - I do in mine & I'm happy with it.

Of course, when you want to run it on those cold mornings, make sure you've got a good battery (to turn the engine over in good fashion) and then once started, let it idle at ~1000rpms for a 3-5 minutes (to allow the oil and everything else warm up some) before raising the rpms & slipping the trans into gear.

Here is my short 'soapbox say' on this subject:

For these old trucks/engines, even if they are rebuilt, the tolerances are very loose compared to engines built in the last 20 years. Nowadays, I don't run my older iron every day, which means I am looking for oils that have some 'cling' to it - in an effort to reduce a 'dry start up' condition.

Now, for my 2-cents worth of experience collected over the past 3.5 decades, I've tried many different oil additives, Mobil 1 and lots of different dino oils in my 60's vehicles.

What I currently run and I am happy with is 4qts of diesel service 15w-40 motor oil (I believe it contains an adequate amount of zinc, for lifter wear protection) and 1qt of LUCAS heavy duty oil stabilizer. My oil consumption has noticeably been reduced, the oil pressure increased slightly and no additional leakages and it "starts quieter".
With this combination, my maintenance costs have not been increased dramatically.

Now back to your regularly-scheduled programing....

BarnieTrk

oldtrucks · Post by **oldtrucks** » October 8, 2011, 5:31 pm

Good soapbox say BarnieTrk. Anyone using that formula with a decent engine of that vintage will never have an oil related problem.

I on the other hand use Mobile 1 15/50 in my 429 / 460 work engines and my 1984 1200 Gold Wing and have never had an oil related failure. By the way, when my engines are running down the highway I like to be between 3000 and 3600 RPM I find they pull the best and get the best fuel mileage at that RPM range.

ICEMAN6166 · Post by **ICEMAN6166** » October 8, 2011, 6:43 pm

BarnieTrk wrote:Daplumma,
Yes, I'd suggest you run the 15W-40 diesel-grade motor oil - I do in mine & I'm happy with it.

Of course, when you want to run it on those cold mornings, make sure you've got a good battery (to turn the engine over in good fashion) and then once started, let it idle at ~1000rpms for a 3-5 minutes (to allow the oil and everything else warm up some) before raising the rpms & slipping the trans into gear.

Here is my short 'soapbox say' on this subject:

For these old trucks/engines, even if they are rebuilt, the tolerances are very loose compared to engines built in the last 20 years. Nowadays, I don't run my older iron every day, which means I am looking for oils that have some 'cling' to it - in an effort to reduce a 'dry start up' condition.

Now, for my 2-cents worth of experience collected over the past 3.5 decades, I've tried many different oil additives, Mobil 1 and lots of different dino oils in my 60's vehicles.

What I currently run and I am happy with is 4qts of diesel service 15w-40 motor oil (I believe it contains an adequate amount of zinc, for lifter wear protection) and 1qt of LUCAS heavy duty oil stabilizer. My oil consumption has noticeably been reduced, the oil pressure increased slightly and no additional leakages and it "starts quieter".
With this combination, my maintenance costs have not been increased dramatically.

Now back to your regularly-scheduled programing....

BarnieTrk

using delo 400 15w40 myself.

only additives i use anymore are marvel mystery oil, lead sub and the occasional bottle of dry gas.

got sucked into extra $ for the fram high mileage oil filters as the Wallys were out or dont carry the standard one anymore.

64 f100 · Post by **64 f100** » October 9, 2011, 10:11 am

Something said here that makes good sence, that is oil that stays in the engine where it belongs. Startup is the hardest time for the engine. As to otherwise, even water will lubricate under certain circumstances, but I would not try it. As to additives, I like slick 50, but not saying it's good for all engines or any of ours. I have not used it in a long time, as I don't feel like it's needed. Bear in mind that oil is oil and the other products in multiviscosity oils may or may not do what is advertised, and no telling if it actually works. I run all of it and frankly it doesn't matter as long as it's getting between the metal parts where it belongs. If, your engine should be running 40 pounds of pressure and it's running 15, it doesn't matter as long as you don't push it hard. When you start punching a worn motor you run the risk of pushing oil out from between the bearings and not having this cushion of oil for these to ride on. Baby a worn engine and it will last a long long time, if not get ready for an overhaul. I personally like to drive things like I stole it. If I have a weak motor it shows up fairly soon after I start driving it.

Rich

ICEMAN6166 · Post by **ICEMAN6166** » October 9, 2011, 10:23 am

64 f100 wrote: As to additives, I like slick 50, but not saying it's good for all engines or any of ours. I have not used it in a long time, as I don't feel like it's needed.

I personally like to drive things like I stole it. If I have a weak motor it shows up fairly soon after I start driving it.

Rich

i used to use that slick 50 every oil change years ago.cant say 100% but i do believe it kept my 390 from seizing when it ran out of oil pressure. it did not save the engine, just got me home.