1966 and all that - THe Growler
Here's one for the armchair experts, (real, imagined and wannabe) from the days when they made proper engines.

One of my '66 Mustangs has covered a known 139,000 miles from new on the original Ford V-8. It is used regularly, consumes virtually no oil between 5,000 km changes, (oil remains cleanish) runs quietly and is still good for over 100 mph. Waterworks are reasonably clean, flushed now and then, although she does get up to the top of the gauge in heavy traffic (but then we don't get many days in Manila less than 30 degrees C.) and traffic is always heavy. The transmission fluid was changed last year for the first time when the pan gasket sprang a leak and the rear axle oil has never been changed (the Ford manual states this is unnecessary). The car has never had any kind of mechanical attention other than normal servicing beyond one new alternator, brakes, hoses and belts from time to time.

My mechanically-minded friends are split between the aviation breed (pull things down at specified intervals regardless) who prophesy the engine's innards (valve springs, head gasket, t/chain) are tiring and should be overhauled before something goes wrong, and the "I used to have one of them" crowd who say leave well alone, "my old man did 350 thou in one of them and never put a wrench on it etc".

Personally I think the original Ford V-8's are fabulous motors and over-engineered in the best of older US auto traditions. Since even a flatout expressway storm seldom pushes it above 3000 rpm it never feels like it's working hard. In fact my current F150 truck's V-8 is similar -- today its engine was turning over at only about 1500 rpm during a 100 kph run, so smooth you couldn't feel or hear it.

Since this has become a regular topic round the bar I said I would seek second, third, fourth &c opinions. By definition I guess these will come from the ..er...more mature contributors. The team who gets the least votes will shout the drinks, needless to say.

Over to the forum........
1966 and all that - jc
It's called "breakdown-maintenance" or "if it ain't broke,don't fix it!!
1966 and all that - David Davies
By the sound of it your Mustang is mechanically very good and certainly does not need an engine overhaul.I would suggest taking time to check for any body corrosion and carry out rustproofing.I have heard that rust in the boot floor can cause the petrol tank to drop out!On the other hand perhaps you do not have these problems in the Phillipines.
One further thought:as your car runs hot in traffic you could try having the radiator recored or renewed and fit a supplementary electric fan.
David Davies (Tune-Up Raglan)
1966 and all that - Richard Hall
Just keep up the servicing, and use the car regularly. I would consider changing the axle oil though - I don't think that whoever wrote the original handbook imagined the car lasting 35 years plus....

Richard Hall
bangernomics.tripod.com
1966 and all that - THe Growler
Thanks, yes. We did replace the rear frame rails and springs about 3 years back, along with the exhaust. No significant rot anywhere else.
1966 and all that - John S
Growler

I'm always impressed how mechanically quiet these big V8's are and any problems with wear, for example timing chain or valve lifters will be audible very early on. Taking the engine apart to change something that isn't faulty will risk introducing dirt that won't be there otherwise. Keep changing the oil and coolant regularly, and only worry when you hear problems. My friends in the US seem to consider 100,000 miles as nicely run in.

Aviation maintenance is governed by rules and regulations on overhaul periods, and the consequences of failure could be more significant.

I'd certainly agree with the advice to change that axle oil though!

Regards

John S