IMHO for an older American car you can't go wrong with a "fleet" oil
like Shell Rotella 15W40 or similar. If you want a synthetic, Mobil 1
Truck and SUV is a similar 5W40. I'd start with a change with Rotella
and see if your friend has any issues with that. Upside: Rotella is
cheap! but full of detergents to keep the engine's insides nice and
Indeed. Motor oils have a letter following the weight. Every so often they
increase the letter to match oils to advances in engines. I remember
having to get rid of my 10W30 F oil and start using 10W30 G. Makes you
wonder what they have done to oil since the 1960's and why.
William R Watt National Capital FreeNet Ottawa's free community network
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A "standard" oil back then was a straight 30 weight, so a 15W40 should
Once the 15W40 is in there, the owner of the car can monitor
temperature, pressure etc. and see if a different viscosity should be
used for the next change.
In the heat of So. Carolina, I like Castrol 20W50. Has been good to us
for older, higher mileage engines, like the older 68-75 Pontiac
350's/400's/455's and similar years Buick 350's & 455's. Using 10W30, oil
lites begin to flicker at idle; switching to Cas. 20W50 would stop both that
AND oil seeming to lose viscosity and letting the oil lite come on when the
engine heated up completely & lifters began to clack. HTH & good luck. s
As you might imagine, this can provoke a lively discussion and a groan
or two on the T-Bird mailing lists (see http://www.tbird.org ).
In my interpretation, house-brand 10W40 is the modern equivalent of
what the owner's manual suggests. Change it about every 3K and use a
quality filter (the Motorcraft FL-1A is readily available and
competitively priced). The five-quart jug is, intentionally, the
right amount for a complete change with new filter.
I run 5W40 or 5W50 synthetic in my '66. The incremental cost of using
synthetic is about ten dollars an oil change, a small fraction of the
cost of operating such a car.
However, I know the history of my car since overhaul. There is much
debate over whether to use synthetics in a "survivor" or older resto
whose past use and maintenance are unknown to you. Some people really
like the new generation of "high mileage" motor oils in a somewhat worn
older car that has the odd leak here and there; cost is about a buck
fifty a quart.
That might be a good choice for the extra bottle you keep in the trunk
(like most cars of the era, they'll consume more oil than we're used to
nowadays -- a quart or so during the change interval is nothing to be
alarmed about if the engine seems healthy otherwise).
I would not try to squeeze out the 6,000 miles between changes that
Ford suggested was possible, unless I was doing highway driving
exclusively. Somewhere in the neighborhood of every 3-4k should be
Have fun with your Bird,
The synthetics have some good points and bad points. Many of them have
very good solvent properties, and will remove huge amounts of gum and
varnish from older engines. This means sticky lifter problems sometimes
go away, but it also means that sometimes you get a lot more oil leakage
The leakage issue is made worse by the fact that the synthetics flow a
lot better than most petroleum oils, so pinhole leaks that were non-issues
turn into big problems.
Personally I have been using Castrol 5W-50 and the Royal Purple 20W-40
synthetics in a variety of older engines and have basically been quite
happy with it. The Castrol seems to have more blowby than the Royal
Purple stuff, which may just be due to the viscosity.
I did have a problem with a stationary engine that seemed to be held
together completely with gum and tar. I tried the Castrol stuff in it,
and the oil filter clogged up after five hours of running time, from
all the junk that was going into solution. That was a horribly-abused
engine before I got it, though.
I'm still trying for 2,500 miles between changes. 480,000 miles on
a crappy Chrysler Laser is a good sign I must be doing something right.
"C'est un Nagra. C'est suisse, et tres, tres precis."
Joe, I usually agree with your advice, but in this case I'm going to
have to respectfully disagree with you. Traditionally, a 10W40
conventional oil has a lot of VI improvers which break down with heat
and mileage, thinning out the oil, which is less than ideal. I'd stick
with either a 10W30 or a 15W40 depending on the requirements of the
engine (if it holds sufficient oil pressure with 10W30 that will
provide better flow and incrementally better mileage, so its use is
preferable IF the engine is "tight" enough to use it.) I basically
mistrust any non-synthetic that has a viscosity spread that large (i.e.
the numbers before and after the "W" are that different.)
Not a bad plan, IF the engine isn't a leak-monster. Since you say it's
been overhauled below, that's probably the best plan for you. One of
the big advantages of synthetic is that it doesn't need as many VI
improvers to have a large viscosity spread, i.e. a 10W40 conventional
oil is iffy but a 5W40 synthetic is probably just fine. This makes
life easier on your starter in cold weather without the need to switch
between a "summer" (e.g. 15W40 or straight 30 weight) and "winter"
(e.g. 10W30 or lighter) oil.
Better yet IMHO than the "high mileage" oils are the "fleet" oils, also
known as HDEO's (Heavy Duty Engine Oils) or "dual rated" (will have an
API Sx/Cx rating for Spark/Compression, or Gasoline/Diesel) oils.
They're cheap, have TONS of detergents and anti-wear additives, and are
often available in gallon jugs for less than a regular 10W30. Most
common weight is 15W40. Two common brands are Shell Rotella and Mobil
Agreed yet again. If the engine is super sludgy inside, you might want
to consider using a fleet oil and changing a couple times at even
shorter intervals, such as 1000 miles or even less if the oil is
getting noticeably dirty before then. A few cycles of this will start
to gently clean the insides of your engine, if you periodically have
the valve covers off you will actually notice the old varnish deposits
softening up and becoming easier to remove.
I should be a bit more specific: I had the overhaul done, and other
people probably haven't driven the car a total of ten feet since then.
(Broke it in on Rotella 15W40 and switched to their 5W40 synthetic,
with an interlude of Castrol 5W50 synthetic when it was cheap for a
while. Great minds think alike.)
Giving advice to people who've bought a used one (or in this case whose
friend has one) is of course rather a lot iffier. Maybe it has a
drive-anywhere engine rebuilt with modern technology, maybe a
well-preserved original that needs and deserves gentle care; maybe a
sabertoothed tiger and a wooly mammoth are slowly sinking into the
So what's the story on 10W40 these days? I know it fell into bad
repute several years ago (after a long period of being more or less the
default substance that people put in their cars), but now it seems to
be all over the place again. Better formulations or just short
We'll take it in for an oil change and find out what's best, it's just
that it was acting funny, like it was going to die, so I thought maybe
it was the oil. It's an original engine I think, a '64 actually. The
oil has not been changed or put in for about 2 years, but it's been
driven very very little, and there is some oil in it still. We just
thought maybe it needed some to even drive to a station. Thanks for all
the advice, I may come back and look this all over again after the oil
change and figure out where to go from there.
Hmmmm. While it could probably stand an oil change, that's not going
to be the problem. You're looking at the need for a tune-up (new
plugs, cap, rotor, points -- I recommend the solid state Pertronix
replacement for them, but I digress), maybe wires);, fuel filter
(probably a succession of several of them a few months apart, given the
amount of rust often in the gas tanks of these old cars -- easiest to
replace with the oil filter off); replacement/enhancement of very aged
gasoline from which all the higher volatiles have evaporated; carb
adjustment; carb rebuild;, or some "hard parts" engine problems
(hopefully THAT one's at the bottom of the list for a reason).
What your friend really needs is a trustworthy mechanic or talented pal
who understands systematic troubleshooting of the oldie-but-goodies.
Again, the appropriate T-Bird mailing list can help there, a lot.
Best of luck,
Oh, and I forgot "vacuum leaks." They call 'em Tee-birds because of
all the golf tees inserted in the vacuum hoses leading to one
dysfunctional accessory or another.
"But seriously, folks": It takes quite a leak to interfere with a 390
or 428 cubic inch vacuum pump. But it is one of the things to look
for (often an older car that has fallen into a state of neglect has
several problems going at the same time).
I'm guessing that a '65 does not have Exhaust Gas Recirculation and the
balky controls thereof, though California-spec cars might have (they
did in model year 1966). It probably does have Positive Crankcase
Ventilation, a far less troublesome system but also one that can cause
(easily rectified) vacuum leaks of larger size than you get from the
interior accessories. A third big-inch vacuum hose serves the power
brakes, as it does in most cars.
(Which reminds me that the brakes will become a big part of your
friend's life; that can be the next topic, after they get 'er running
well enough to consider actually using the car. There are some
model-specific concerns there, over and above the general desirability
of taking a *real* close look at the system. While they home in on the
state-of-tune/driveability problems, I'll dig up an old posting about
T-bird brakes specifically, and some related issues.)
What is the story on the engine? Is it an original un-opened engine? Low
miles? High miles? Does it consume oil?
If its a tight, non-leaking, non-oil burning engine and you want the
very best protection for it, go with a synthetic 10w30 or thereabouts.
If its a bit of an oil burner, go with a cheaper non-synthetic, but I'd
still recommend 10w30 or maybe 15w50.
Forget those "high mileage" oils- they're just regular oil with some
spoo in them to make the seals swell. They'll ultimately shorten the
life of the seals though.
If its a fresh rebuild, DEFINITELY go with the best (synthetic) oil you
can buy, at least after the intial break-in. Tolerances and clearances
in engines from the 60s are almost identical to modern engines anyway-
in fact the ONLY real difference is modern engines with hypereutectic
pistons (and people frequently rebuild 60s engines with HE pistons now
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