0W-40 in 1970 Cadillac Eldorado

62,000 original miles.


> How many miles and years on the engine. *If it's a long time I would
> just switch to 5w30 non-synthetic. *Running synthetic in an old engine
> could cause it to start leaking. *For those cold northeast mornings
> just install a block heater and solve any cold start worries.

"John S." > wrote in message
...
On Feb 16, 9:34 am, The Derfer > wrote:
> I've got a great old 1970 Cadillac Eldorado.
> The 500 CI motor at its highest-rated-ever 400 HP.
>
> Living in the Northeast, it's cold here a lot of the year, especially
> in the morning. Though I hardly ever start it up on a cold morning,
> I wonder about the overall stress and strain to the engine when it's
> bone-cold out there and I'm using (typically) 10W-40 motor oil.
> I've used synthetic and conventional at times, and even 10W-30
> here and there. None of them have caused any noticeable problems.
>
> Would switching to something like Mobil-1 synthetic 0W-40 be a good
> idea to get the oil flowing quicker and more easily to the various
> engine
> parts in cold weather? I ask because the only cars which are ever
> recommended for usage of 0W-40 seem to be European luxury and
> sports sedans, not this classic road barge of old. Plus Mobil-1 in
> particular seems to be recommending the "0W" grade wherever the "5W"
> or "10W" would normally be used such as to promote better cold starts
> and increase fuel economy. This, especially with its "Advanced Fuel
> Economy"
> line of oils (e.g., use 0W-20 where you'd normally use 5W-20).
> Although since #W-40 oils aren't offered in that line, I'd consider
> regular
> Mobil-1 0W-40. Any advice on this? Good idea? Bad idea?

How many miles and years on the engine. If it's a long time I would
just switch to 5w30 non-synthetic. Running synthetic in an old engine
could cause it to start leaking. For those cold northeast mornings
just install a block heater and solve any cold start worries.
=========

Good advice.

"ray" > wrote in message
...
>>
>> I've used 15W-50 Mobil-1 synthetic and other grades of conventional
>> oil
>> (10W-30 up to 20W-50) before. None produced any ill effects that I
>> can
>> report. The engine does leak oil to a degree and none of those oils
>> made
>> it better (or worse). My real question is would 0W-40 make for easier
>> starts
>> in the cold? I want to make the engine last (never have to rebuild
>> or replace)
>> so synthetic is an option I'm thinking of returning to, and perhaps
>> 0W-40
>> is the right grade for every situation. But if people have other
>> ideas, I'm
>> always listening.
>>
>
>
> You may wish to investigate GM EOS or Shell Rotella - something high in
> zinc for your engine, especially if you want it to live forever.


Shell Rotella is a GREAT oil for that engine.

On Feb 18, 5:57*am, "KRP" > wrote:
> "ray" > wrote in message
>
> ...
>
>
>
>
>
>
>
> >> I've used 15W-50 Mobil-1 synthetic and other grades of conventional
> >> oil
> >> (10W-30 up to 20W-50) before. *None produced any ill effects that I
> >> can
> >> report. *The engine does leak oil to a degree and none of those oils
> >> made
> >> it better (or worse). *My real question is would 0W-40 make for easier
> >> starts
> >> in the cold? * I want to make the engine last (never have to rebuild
> >> or replace)
> >> so synthetic is an option I'm thinking of returning to, and perhaps
> >> 0W-40
> >> is the right grade for every situation. *But if people have other
> >> ideas, I'm
> >> always listening.
>
> > You may wish to investigate GM EOS or Shell Rotella - something high in
> > zinc for your engine, especially if you want it to live forever.
>
> * * Shell Rotella is a GREAT oil for that engine.

Again, I have tried the Rotella synthetic 5W40 in my Porsche 944 and
found the Mobil 1 of the same grade to hold higher oil pressure at
speed. just my experiences... have not experienced this with cooler-
running Studebaker V-8s however (those I've been running the regular
dino 15W40 though.)

nate

"N8N" > wrote in message
...

> >> I've used 15W-50 Mobil-1 synthetic and other grades of conventional
> >> oil
> >> (10W-30 up to 20W-50) before. None produced any ill effects that I
> >> can
> >> report. The engine does leak oil to a degree and none of those oils
> >> made
> >> it better (or worse). My real question is would 0W-40 make for easier
> >> starts
> >> in the cold? I want to make the engine last (never have to rebuild
> >> or replace)
> >> so synthetic is an option I'm thinking of returning to, and perhaps
> >> 0W-40
> >> is the right grade for every situation. But if people have other
> >> ideas, I'm
> >> always listening.
>
> > You may wish to investigate GM EOS or Shell Rotella - something high in
> > zinc for your engine, especially if you want it to live forever.
>
> Shell Rotella is a GREAT oil for that engine.

Again, I have tried the Rotella synthetic 5W40 in my Porsche 944 and
found the Mobil 1 of the same grade to hold higher oil pressure at
speed. just my experiences... have not experienced this with cooler-
running Studebaker V-8s however (those I've been running the regular
dino 15W40 though.)

There are two Shell Rotella oils. One is a high quality conventional motor
oil. That was the one he was referring to. It is an extreme duty oil used
lots in trucks.As far as synthetics, until Castrol came out with "EDGE"
Mobil 1 ruled the roost. There are several GOOD standard motor oils. The
problem with the Eldo 500CID is that in the 70's it was burdened with lots
of Ralph Nader imposed gee-gaws that really screwed the motor. Get all the
crap off it, set it up right from a fresh build and it's a great motor.
Well, at least a good one. I had one, they regularly ate valves among other
things. Plus the Eldo was a bloated turkey 900 tons and really junk front
wheel drive. It was a nice riding car, but NOT a pleasure to own. The paint
on the 70's Cadillacs was also awful. Mine was medium metallic blue. it
cracked all over like a cheap egg. Nothing you could do but strip it to bare
metal and work your way back up. GM repainted mine several times. The last
time they authorized taking it to bare metal. Both the primer and paint were
crap, so I bought some BASF primer and used FORD paint. It didn't crack
again. Oh and the CV joints. MAYBE 10,000 miles before they started playing
loose marbles in a can. It really wasn't the best car Caddy ever built.

Try Castrol Edge in your pound puppy, you'll like it.

> There are several GOOD standard motor oils. The
> problem with the Eldo 500CID is that in the 70's it was burdened with lots
> of Ralph Nader imposed gee-gaws that really screwed the motor. Get all the
> crap off it, set it up right from a fresh build and it's a great motor.

But the regulations and devices you speak of are
all post-1970, right? Cat converters etc came out
later in the 1970s (so I thought). Am I right?
This car took regular gas. I add lead substitute
once every few tankfulls. (Should I add it more
often?)

On 2009-02-18, The Derfer > wrote:
>
>> There are several GOOD standard motor oils. The
>> problem with the Eldo 500CID is that in the 70's it was burdened with lots
>> of Ralph Nader imposed gee-gaws that really screwed the motor. Get all the
>> crap off it, set it up right from a fresh build and it's a great motor.
>
> But the regulations and devices you speak of are
> all post-1970, right? Cat converters etc came out
> later in the 1970s (so I thought). Am I right?
> This car took regular gas. I add lead substitute
> once every few tankfulls. (Should I add it more
> often?)

Unless the car was originally sold in CA all it would have on it would
be a PCV valve (which only cycles the crankcase vapors back into the
intake with no/insignificant performance loss). Maybe EGR, but I think
EGR was later than '70.

49 state emissions didn't get air pumps and the rest of the add on's
until the mid 70s. They got really bad for '75 up models.

"The Derfer" > wrote in message
...
>
>> There are several GOOD standard motor oils. The
>> problem with the Eldo 500CID is that in the 70's it was burdened with
>> lots
>> of Ralph Nader imposed gee-gaws that really screwed the motor. Get all
>> the
>> crap off it, set it up right from a fresh build and it's a great motor.

> But the regulations and devices you speak of are
> all post-1970, right? Cat converters etc came out
> later in the 1970s (so I thought). Am I right?
> This car took regular gas. I add lead substitute
> once every few tankfulls. (Should I add it more
> often?)

My Eldo was a 74 it had so much CRAP under the hood you barely could see
the engine. PCV and all that crap. I am not sure of 1970. But by 74 the
engine compartment was filled with junk.
Mine took Premium. Regular would knock like a diesel. I thought Tony
Orlando was under the hood. (Knock 3 times.) Could NOT keep CV joints on the
car. Today it makes little difference, you have to add a lead substitute or
the valve stems burn up. Lead was a lubricant. All in all it was NOT
Caddy's best effort.

"Brent" > wrote in message
...
> On 2009-02-18, The Derfer > wrote:
>>
>>> There are several GOOD standard motor oils. The
>>> problem with the Eldo 500CID is that in the 70's it was burdened with
>>> lots
>>> of Ralph Nader imposed gee-gaws that really screwed the motor. Get all
>>> the
>>> crap off it, set it up right from a fresh build and it's a great motor.
>>
>> But the regulations and devices you speak of are
>> all post-1970, right? Cat converters etc came out
>> later in the 1970s (so I thought). Am I right?
>> This car took regular gas. I add lead substitute
>> once every few tankfulls. (Should I add it more
>> often?)
>
> Unless the car was originally sold in CA all it would have on it would
> be a PCV valve (which only cycles the crankcase vapors back into the
> intake with no/insignificant performance loss). Maybe EGR, but I think
> EGR was later than '70.

My 74 had all that crap on it.

Why is Mobil-1 0W-40 referred to as a "Eurpoean Car formula"?