How bad were oils in the 1980’s?
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My dad got 140k out of a 74 beetle before he wrecked it. My 1978 Toyota pickup dropped a valve @ 312k running Valvoline 10w40 back then. It was spotlessly clean under the valve cover
They can't have been that bad. My 1986 Volvo 740 Turbo had an oil cooled turbo (they were also water cooled from 1987 on). I changed the oil every 3 months and drove it for 18 1/2 years and 285,000 Km (180,000 miles). So 2500 mile changes on average.
We lived for that entire time in cities that were very cold in the winter, and we drove the car fast in hot and mountainous areas in the summer.
I did take some precautions like not getting on the throttle after a really cold start until the indicator was off the pin, letting the turbo cool down as I came into our neighbourhood, and letting the engine idle for a few minutes before shutting it off after driving at highway speeds. And the turbo (and the engine) were still fine when I sold it.
PS I used Pennzoil PZL Turbo oil for some part of those 18 1/2 years. So "wax" must be good for turbos too.
We lived for that entire time in cities that were very cold in the winter, and we drove the car fast in hot and mountainous areas in the summer.
I did take some precautions like not getting on the throttle after a really cold start until the indicator was off the pin, letting the turbo cool down as I came into our neighbourhood, and letting the engine idle for a few minutes before shutting it off after driving at highway speeds. And the turbo (and the engine) were still fine when I sold it.
PS I used Pennzoil PZL Turbo oil for some part of those 18 1/2 years. So "wax" must be good for turbos too.
Unleaded gas and electronic ignition brought us this OCI and the 30k spark plug/ tuneup interval. Longer maintenance intervals were about all the 70s had to brag about.
I remember the 70 and 80s oil quality. Pennzoil had the best magazine commercials in the form of a written forum, about how good there oil was. There favorite response was that the new oil turning black was a good sign, as it's cleaning the engine. Where did the engine get the dirt/sludge in the first place?
For my usage, which was most short trips, the oil would stay clean up to 2000 miles, then turn dark at 2500 miles followed by adding sludge to the valve covers with continued use. Havoline and Caster Oil performed about the same. Pennzoil would also place about 1/4" of carbon on the intake valves of my 442 Olds within 1000 miles. I found this while I was pulling the intake manifold to replace a severely bent pushrod.
Valvoline was the good stuff to use back then with Rotella being better. Since then, I've found that Rotella and Shaffers 5w-40 works really good in gas engines. I rebuilt a 2002 BMW engine in the mid 80's that saw 3000 mile Caster OIl changes. It had 1/8" of asphalt coating the inside of the motor. At 80,000 miles all of the rocker arms, pistons and the rest were worn out.
For my usage, which was most short trips, the oil would stay clean up to 2000 miles, then turn dark at 2500 miles followed by adding sludge to the valve covers with continued use. Havoline and Caster Oil performed about the same. Pennzoil would also place about 1/4" of carbon on the intake valves of my 442 Olds within 1000 miles. I found this while I was pulling the intake manifold to replace a severely bent pushrod.
Valvoline was the good stuff to use back then with Rotella being better. Since then, I've found that Rotella and Shaffers 5w-40 works really good in gas engines. I rebuilt a 2002 BMW engine in the mid 80's that saw 3000 mile Caster OIl changes. It had 1/8" of asphalt coating the inside of the motor. At 80,000 miles all of the rocker arms, pistons and the rest were worn out.
+1
Mobil even took a BMW e30 to 1 million miles with their syn oil and the engine was still within manufacturer specs.
ftfy
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Yeah, 5W-30 had a lot of VII, and more importantly, HTHS hadn't been introduced into SAE J300 yet. After HTHS was introduced into SAE J300 in the 1990s, 5W-30 became more similar to 10W-30. Even today, a 10W-30 will typically be thicker in the valvetrain because shear rates far exceed 1,000,000 s⁻¹ there (HTHS shear rate), but it is a lot less of a concern now. A synthetic 5W-30 may even be stouter than a conventional 10W-30 these days as far as the base-oil viscosity (what I call HTFS, which is extrapolated to infinite shear rate) is concerned. See my table for how 5W-30 and 10W-30 HTFS values compare.
Gokhan's estimated base-oil viscosity (HTFS) and VII content table
I do recall a particularly odd oil situation in the mid to late 80’s that would imply that oils were not very well formulated and/or quality controlled. Was doing an oil change on my dad’s Oldsmobile. It was a very cold day (probably between 5-15F) and as i recall it was Exxon Superflo 10W-30 that was going to be poured into the engine. The oil would not pour. It looked like amber colored tapioca pudding. Being young and not so bright, i squeezed the oil into the crankcase. Definitely very odd. Had never seen anything like it before or after. I think the engine was warm enough to melt the jellied oil, and the weather following the oil change must have been warmer, otherwise i don’t think the engine would crank too well. I am guessing that this oil was a not within normal specs.
GM used to strongly recommend against using 10W-40
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We had open loop control, carburetors, vacuum timing advance, and electric chokes that stuck partway on forever when it was cold. Its amazing we got 3000 miles out of any oil with those conditions.
The eighties where when Group II base stocks were starting to be commonly produced and refiners started bringing hydrotreating processes on line to replace the old solvent refining.
The cars were getting better.
The quart oil cans and pouring spouts sucked. Leaks and another thing to have to clean up.
Castrol was the household favorite, along with Pennzoil. ARCO Graphite was tried once, but not again.
Still have some leftover Pennzoil oil filters from that time somewhere in the garage.
It's funny how parental suggestions persist throughout our lives! My dad insisted that I always use Pennzoil. To this day, I still remember those words when i enter the oil aisle, and I look for Pennzoil first. Fortunately I have at least enough common sense to realize that certifications are better determinants of oil quality than brand; sale prices or rebates (among major brands) determine what I actually buy.
Wear wasn’t the problem and hasn’t been for many years prior to the 80s. It was deposit control, oxidation resistance and ring sticking prevention. Extended drains exacerbated the problems.
Do you or anybody else remember what the oil would have looked like for the boutique brands like red line, amsoil or neo? Or they also in metal like cans or had they already converted over to plastic? All I remember when I was real little was that you changed oil every 2 or 3,000 miles religiously.