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1971 Cadillac and Unleaded Gas

The person who called in today questioning the use unleaded gasoline in his 1971 Cadillac has nothing to worry about. It should state in his owner’s manual that all 1971 General Motors cars are designed to operate on unleaded gasoline but the use of a higher octane than the regular grade unleaded used today should be used. I used the mid grade for years in, yes, a 1971 model year GM vehicle, and had no problems.

So I understand Tom & Ray are quitting us. Dang! I hate it when stuff like that happens. Wish you would stay.

Will miss you much. All these years, lot of water over the dame and under the bridge. Great call-ins. Interesting stuff. Great advice. Good laughs. Most of all, not so common these days, great community spirit! Thanks. That would be genuine 100% natural, organic, and Kosher for Passover thanks. Like man, cross my heart and hope to die THANKS.

I’ve a suggestion for you though: Go out with bang. Much grace. Great dignity. Present an award, something great like maybe a tank of gas, to best-of-all-time call-inner. I nominate David of MO [Caller #7 Jun 30, 2012] the paper boy lusting for the 71 Cadillac Seville. The old rich man’s car that he had to place the newspaper inside each a.m. Boy longing for that car. Grows up. Buys that car. Way to go, Paper Boy! Amazing grace. Life does have its moments of splendor!

Sure wish you luck with your car, Paper Boy (Scuse me, please, I guess that now would be Paper Man, or maybe something like Mr. Dr. General Captain Chief David of Missouri. Either way, I’m sure glad you got your car. Drive it in joyous good health!

Also, I wish the Brothers Tom and Ray lots of luck in retirement. Many thanks for all those wonderful stories, so many of which the Missouri Paper Man with his 71 Cadillac Seville is only one bright shining example!

Caio now. mox in sc

any good auto parts store should have a lead additive on the shelf i know i do at work(south jersey)not a bad idea every 3rd or 4th tank .

I have an early 70’s Ford truck and have been using unleaded 87 octane (regular) as long as I can remember, ever since unleaded became the only option, and never had any problem with the valves. I’ve never done much in the way of high-speed multiple-hours freeway driving w/that truck though since unleaded became the only option. It could be that some types of intense operating conditions might be harder on the valves than others w/ engines designed originally for leaded gasoline. All I can say is my early 70’s Ford truck hasn’t developed and valve symptoms using unleaded for years.

Most of those old vehicles will run forever on unleaded with no problems at all. Many of them, especially Cadillacs, have a high nickle content in the cast iron and it’s really not a big issue at all.

A local farmer who passed away just a couple of years ago still drove his '65 Chevy Bel Air and his mid 50s GMC pickup on a daily basis for decades on unleaded gas with no problems.
He had purchased those vehicles new back in the day and was content with them all of those years. To look at him in the old overalls and those bottom of the line vehicles one would think he didn’t have a dollar to his name but he was loaded.

After his passing his relatives sold the Bel Air I think and kept the GMC truck which is still being used regularly.

Amoco ‘White’ was the highest priced fuel on the market in the 1960s and Cadillac recommended using it. ‘White’ meant unleaded. I believe it was 100 octane. It was obvious when a well maintained car was using unleaded 50 years ago because the tail pipe would not have the “chalk dust” appearance on the tail pipe caused by lead salts. Car lots would brag when a car had “chalked pipes.”