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Rust in the 70's

5203 Views 15 Replies 10 Participants Last post by  SDCaddyLacky
From about 1973 until the early 80's Cadillac and even Oldsmobiles were suffering from major rust issues in their bodies.
I recall my '75 Eldorado developing rust blisters when it was only 3 years old.
My mom's '73 Cutlass Supreme coupe had a hole big enough in the right quarter to chuck a cat through.
My dad's 76 Sedan de Ville had blisters behind the side moldings in under 4 years.
It was a serious mess all over GM.
I think Buick and maybe Pontiac suffered with it too.
Was GM sued?
What was the cause? Dissimilar metals causing electrolysis? Poor assembly procedure? Crummy materials?
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What about rust in the early Vegas.
I went into a Massachusetts Chevrolet dealership in the summer of 1972 to lookover a fleet of 50 used Vegas they had shipped from Florida. These were all '71's with 15,000 miles or less.
Over half of them already were displaying rust behind the front and rear window moldings.
They must have been parked near the ocean or in a very humid climate.
Some even showed small rust blister popping out on the top of the front fenders near the windshield area.
These GM beauties were only a year old!
In 1977 back at the same Chevrolet dealership a salesman who I was friendly with showed me a craem colored '75 Cadillac SDV 4 door. The right side was so badly rusted thru that my buddy told me they were going to replace the 2 right doors and probably patch the front fender and right quarter before they could resell it.
The Cadillac was traded from a fisherman from Plymouth who parked it every day on the docks in the harbor. The passenger side always faced the ocean in his assigned spot.
You could see the entire window mechanisms through the gaping holes in those doors. The left side was perfect as you'd expect a 2 year old car to be.
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I had a 72 Montego. It had such a huge hole in the rear quarter that when I went around a corner, cans of oil (which I had to carry because it used so much) would roll around in the trunk and fall out on the road. Remember oil cans?
Grandparents had a 77 CDV. The frame rusted thru and the whole back of the car was sagging. I didn't see it, but my grandmother drove it in to the dealer to trade it with a big rope going from the front to the back, over the roof.
Things sure have changed.
Jeff
It had to do with poorly galvanized and treated metal, plus lots of areas that trapped water. From 1977, Cadillac at least started using better anti rust methods so they were less prone to rust then they had been. However, if the car was in a high salt environment like the northeast or near the ocean, rust was still a problem.
My 68 tells me that some components had to have been inferior metal, or poorly treated in some way. The other big problem is the areas that collected water, mud, snow very easily, such as the trunk area,
fender bottoms, drainage holes in frame, etc. Its funny how they made such a great drivetrain but couldnt figure out basic sheet metal 101. I'm from the newer generation so I'm used to cars being disposable,
but I feel like the 50s,60s,70s people were used to replacing cars every 5 years as if they were worn out. Is that the way it really was? If I was GM, Ford, Dodge I would have been thinking I had a license
to print money because people just keep buying the stuff so often.
My '65 Chevelle and a companion '65 Pontiac LeMans had serious rust problems at the lower corners of the rear window channel. Even a '72 Volvo wagon was a real corrosion turd.

Many older - 30s, 40s, 50s- cars had recurring rust and corrosion problems. Today, with better corrosion control, metallurgy and paint application technique we see nothing like "the old days"........... BUT, some rust belt cars fall apart in 5 years even now.

Unless you were a dedicated fanatic gearhead most 60s cars were toast by 75,000 - 90,000 miles, engines included. Rear ends ran forever (if you were easy on the clutch and rpm !)
It had to do with poorly galvanized and treated metal, plus lots of areas that trapped water. From 1977, Cadillac at least started using better anti rust methods so they were less prone to rust then they had been. However, if the car was in a high salt environment like the northeast or near the ocean, rust was still a problem.
^^^ Are you kidding? They didn't galvanize car body sections until the 1990's, the only kind of rust inhibitor offered was the dealer installed (sometimes manufacturer installed) bitumin based under body sealer. "Winter" underbody sealing was big business back in those days, not that it was very effective in keeping a car rust free.

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My 68 tells me that some components had to have been inferior metal, or poorly treated in some way. The other big problem is the areas that collected water, mud, snow very easily, such as the trunk area,
fender bottoms, drainage holes in frame, etc. Its funny how they made such a great drivetrain but couldnt figure out basic sheet metal 101. I'm from the newer generation so I'm used to cars being disposable,
but I feel like the 50s,60s,70s people were used to replacing cars every 5 years as if they were worn out. Is that the way it really was? If I was GM, Ford, Dodge I would have been thinking I had a license
to print money because people just keep buying the stuff so often.
As I have said many times, cars began to deteriorate after a year's use and rattle traps by the end of the second year. Poor build quality and even worse assembly of the fifties and sixties cars made for their rapid turnover by their original owners. The first American car that I owned that still felt new after two years was mu '76 Seville. Cadillac's quality improved greatly in the late seventies. But rust was still a big problem in states that used salt on their roads.

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My '65 Chevelle and a companion '65 Pontiac LeMans had serious rust problems at the lower corners of the rear window channel. Even a '72 Volvo wagon was a real corrosion turd.

Many older - 30s, 40s, 50s- cars had recurring rust and corrosion problems. Today, with better corrosion control, metallurgy and paint application technique we see nothing like "the old days"........... BUT, some rust belt cars fall apart in 5 years even now.

Unless you were a dedicated fanatic gearhead most 60s cars were toast by 75,000 - 90,000 miles, engines included. Rear ends ran forever (if you were easy on the clutch and rpm !)
^^^ Actually, we thought 50,000 miles was about it for cars of that era.
As I read this, I am watching an old episode of Emergency. I love looking at all those brand new "old" rustfree cars.
Jeff
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Yeah, I love that too! CHiPs is great for that too.

Especially love seeing the "unloved" old 4 doors and wagons that are missing at most classic car events.
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drewsdeville said:
I recall Ford Galaxies using galvanized panels in 1967 and Mercury Comets having galvanized panels in the early to mid 60's.
All or most 70's cars had major rust issues. My 72 Cadillac Deville had rust chunks forming from the vinyl top. My 78 Lincoln Continental had rust holes going thru into the trunk near the trunk lid that I had to fix with new sheetmetal and paint,


I think the only true luxury cars that galvanized their bodies were the 60's Lincoln Continentals for rust superior rust protection. Which is maybe whey they have held up for so long.

Also heard that Fords constructed better bodies and used better materials over anything GM was making back then,
Unless you were a dedicated fanatic gearhead most 60s cars were toast by 75,000 - 90,000 miles, engines included. Rear ends ran forever (if you were easy on the clutch and rpm !)
Quite a few '60s cars ran up to and over 100,000 miles with the original engines and drivetrain. My former '66 Dodge Dart GT V-8 already had 109,000 miles when I took ownership. The engine was rebuilt in 1990 at about 170,000 miles and I did not baby that car... numerous burnouts and winding out 1st gear to 40 mph and second to 70 mph. It was still running fine and had plenty of power, but was burning too much oil. The first radiator trouble/leaks did not happen until 1984 (at about 145,000 miles) when a pinhole leak appeared at the top of the radiator. My mom's '70 Coupe de Ville passed the 200,000 mile mark with the original transmission and engine (engine did have a valve job shortly before she took ownership in 1988).

My brother's '66 Plymouth Fury III (318 V-8 engine) also lasted a long time.

If I went into a time machine back to the mid-'60s and bought a Cadillac or Mopar, I would be very confident it would last 100,000+ miles and 20 years with no major problems.
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I had much the same experience with the 71 Monte Carlo.
Bought new by dad, raced nightly by me from the time I was 15:shhh: until I bought my van at 18.
When we sold it in 1984 with 134,000 miles on it the only thing my dad had ever done other than routine maintenance was a timing chain at about 90,000.
I beat the snot out of that poor car and it was a trooper.
I had much the same experience with the 71 Monte Carlo.
Bought new by dad, raced nightly by me from the time I was 15:shhh: until I bought my van at 18.
When we sold it in 1984 with 134,000 miles on it the only thing my dad had ever done other than routine maintenance was a timing chain at about 90,000.
I beat the snot out of that poor car and it was a trooper.
Yes, quite a few '60s engines were very rugged and lasted a long time. A few examples would be the 390 and 472 (and '70s 500) Cadillac, Mopar slant six (170- and 225- cu in), the Mopar 273, 318 and 340 and the Mopar 383 and 440. Also the 283, 327 and 350 Chevy. The 390 Ford engine seemed to be well-built. Also the Buick 401 and Olds & Pontiac 400-cu-in V-8. I know I am leaving some out!
It's funny because I just watched a bunch of youtube video's on older cars from the 30's all the way up to the 70's. One video that I am sure some of you here have seen is the one regarding the 62 Cadillac promitional video and how it explains it's quality, value and performance.

Some of the old vids I saw spoke about rust proofing and how it was done. Bodies being fully dipped in electrostatic primer so that every nook and cranny was protected from rusting. I mean the engineers knew about rust prevention forever it seems, but yet nobody can explain the ferocity of rusty cars from the 30's all the way up to 70's. Even the best efforts in those days just wasn't enough it seemed. It's crazy to think it's taken so long up until the last 10-20 years where automakers have finally been able to prevent and even stop rust in it's tracks.

I also feel that in the 70's, the metal quality probably did get worse in terms of corrosion resistance even quality compared to the cars built in the 50's and 60's. Poor drainage, and styling choices for many cars during this time made it pretty much impossible to build a completely rust proof vehicle.

It's very obvious that today, you really don't have to worry about rust anymore, beside for the people that live in the mid west and east coasts where the underbodies are still prone to severe corrosion. The modern car lacks unique shapes to trap water, plus cars today are designed with drainage in mind and zero places for water to be trapped in.

Climate matters a lot here, many people think that cars from California are rust free and perfect, this is far from the truth. My 64 Cadillac is an original CA car purchased from an L.A. area Cad dealership back in the day, but the owner lived in Huntington Beach where the salt in the air has cause surface rust, and rust blistering over many sections of the car including the underbody parts. Even where I live in CA, we still get humidity at night, so the dew point moisture that sits on top of the car from the late evening hours to early mornings can cause rusting as well.

The only CA cars that are truly not affected by rust is if they were located more inland or further east towards the mountains and desert regions of the state. Even being 10 miles away from the ocean in CA can still cause damage or further increase rusting problems on a classic.

I knew a guy that lived in Pacific Beach in San Diego, he owned a 60 Mercury Meteor. That car had so much rust all over the body that it looked like it had been from Chicago went to Detroit, and headed back to California, that is how much rust there was on the Merc and his car was also a original CA car.

Rust sucks.
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