Castrol GTX was so popular in the 80's through the early 90's everyone I knew used it in all oil weights.
Late 80s/early 90s oil tech
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I used it mostly in my 89 mazda 323 hatch and I got varnish sometime after 100k. now with the newer and syn oils I have nothing at 193k!
Since this sludging issue has come up, I'd like to address some of it. Those engines that sludged, ran pretty cool. 180* thermostats were common back then and a lot of guys put 165* (salt water marine) thermostats in their engines thinking they were saving themselves trouble down the road. Sludge is a common issue in over cooled marine engines. Hence teh TBN of 15 in MobilGuard marine lube ...
Somewhere in the 1980's the OEM's started going up in normal operating temps. 195* thermostats became the norm and a few started running 200* ... The sludge disappeared. It was a confluence of better oils and higher constant temps.
Even today, short tripper who drive a few miles and shut their engines off, then drive a few miles home can have sludge issues. It has to do with heat, not basic chemistry. You leave condensation in an engine and don't boil the water off, you will make sludge (water/oil emulsion baked on).
Pennzoil was not really any worse than anyone else. But they got a lot of flack for it anyway. I still hauled Pennzoil 10W30 and SAE30 to buss and truck yards all over the west from their facility in Alameda. None of those fleet operators had any issue with Pennz as fleet fills. No sludge anywhere - why - those engines ran all day, got hot and stayed that way ...
Somewhere in the 1980's the OEM's started going up in normal operating temps. 195* thermostats became the norm and a few started running 200* ... The sludge disappeared. It was a confluence of better oils and higher constant temps.
Even today, short tripper who drive a few miles and shut their engines off, then drive a few miles home can have sludge issues. It has to do with heat, not basic chemistry. You leave condensation in an engine and don't boil the water off, you will make sludge (water/oil emulsion baked on).
Pennzoil was not really any worse than anyone else. But they got a lot of flack for it anyway. I still hauled Pennzoil 10W30 and SAE30 to buss and truck yards all over the west from their facility in Alameda. None of those fleet operators had any issue with Pennz as fleet fills. No sludge anywhere - why - those engines ran all day, got hot and stayed that way ...
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Mobil 1 originally recommended a 25k mile OCI.
Then there's this 1976 Popular Science article
An engineer/consultant planned to do 5yr/100k OCIs.
Then there's this 1976 Popular Science article
An engineer/consultant planned to do 5yr/100k OCIs.
Back in the day, oil came in metal cans and you had to punch a metal spout through the top of the can.
A real pro could punch a hole in the can and pour the oil freehand without spilling a drop.
A lot of people had oily engines because they tried the pro technique and failed. The oil stains on the ground in parking lots were a lot bigger and darker back then too.
A real pro could punch a hole in the can and pour the oil freehand without spilling a drop.
A lot of people had oily engines because they tried the pro technique and failed. The oil stains on the ground in parking lots were a lot bigger and darker back then too.
Originally Posted By: Evili
Back in the day, oil came in metal cans and you had to punch a metal spout through the top of the can.
A real pro could punch a hole in the can and pour the oil freehand without spilling a drop.
A lot of people had oily engines because they tried the pro technique and failed. The oil stains on the ground in parking lots were a lot bigger and darker back then too.
Welcome to BITOG Evili, are you new here?
Back in the day, oil came in metal cans and you had to punch a metal spout through the top of the can.
A real pro could punch a hole in the can and pour the oil freehand without spilling a drop.
A lot of people had oily engines because they tried the pro technique and failed. The oil stains on the ground in parking lots were a lot bigger and darker back then too.
Welcome to BITOG Evili, are you new here?
I miss the oil cans that was stack up neatly in a rack at the "service station" between the regular leaded gas of 89 octane and 87 unleaded. The oil can started going away around 86 and we had a spout at the house that took some skill to push it in correctly. You couldn't use the spout on the HD SAE 30 lawnmower mower oil, because it would flow too fast and you needed a screwdriver for 2 holes so it would pour slowly, plus let air in at the top for a smooth flow.
Mobil One was the only Synthetic I knew of and we didn't understand why we should buy it at $4 a quart, when you could get a case of GTX or Havoline for less than $10. Castrol GTX was real popular and had a mystique about it, since it was kinda new to us and didn't have the name of a major oil company on it. Everyone used 10W 40 or 20W 50 in their cars that I knew of, even if the engine requested something else. I remember a Chevy 305 ci Caprice we had in the late 80's, it called for 5W 30 and there was no way we were going to put that thin GTX bottle with a white top in there, it was getting 10w 40! The turbos were starting to take off around the late 80's and most oil companies had "turbo approved" on the bottle. Recycling oil meant you returned the oil to where it came from and that was in the ground where you were changing it in, or in the ground behind the barn!
Every Ford used a FL1A filter and had been doing so for at least 30 years. We had a 72 F250 360ci and a 88 F250 351 using the same filter. It also fit my 302 Mustang GT and an old 1960 something Ford tractor, I still use the Fl1a on my 96 Ram 1500.
There were some odd weights of oil back then. Pennzoil had a 20w 20 and Motorcraft had the 20W 40 in the cool looking white bottle with red label, unlike the uncool brown Motorcraft bottles. I think Motorcraft even had a 10W 50 back then.
The first non Mobil One synthetic I used was Castrol Syntec in 1993. The only place I could find it was at Pep Boys which was a big deal back then, because all the other parts store we knew of were mom and pops, or mom and pop with a Napa or Western Auto sign. The only option I had at Pep Boys in Syntec was an odd weight of 15W 40, which is normal in the trucking world, but not in passenger cars.
The jugs of oil started coming out in the mid 90's and they were gallons at first. So you bought a gallon plus 1 quart, because nothing used 4 quarts then that you would be caught driving, then they wised up and made the 5 quart bottle. The 5qt bottle hit the spot, unless you had a Ford that wanted 6 plus quarts.
Mobil One was the only Synthetic I knew of and we didn't understand why we should buy it at $4 a quart, when you could get a case of GTX or Havoline for less than $10. Castrol GTX was real popular and had a mystique about it, since it was kinda new to us and didn't have the name of a major oil company on it. Everyone used 10W 40 or 20W 50 in their cars that I knew of, even if the engine requested something else. I remember a Chevy 305 ci Caprice we had in the late 80's, it called for 5W 30 and there was no way we were going to put that thin GTX bottle with a white top in there, it was getting 10w 40! The turbos were starting to take off around the late 80's and most oil companies had "turbo approved" on the bottle. Recycling oil meant you returned the oil to where it came from and that was in the ground where you were changing it in, or in the ground behind the barn!
Every Ford used a FL1A filter and had been doing so for at least 30 years. We had a 72 F250 360ci and a 88 F250 351 using the same filter. It also fit my 302 Mustang GT and an old 1960 something Ford tractor, I still use the Fl1a on my 96 Ram 1500.
There were some odd weights of oil back then. Pennzoil had a 20w 20 and Motorcraft had the 20W 40 in the cool looking white bottle with red label, unlike the uncool brown Motorcraft bottles. I think Motorcraft even had a 10W 50 back then.
The first non Mobil One synthetic I used was Castrol Syntec in 1993. The only place I could find it was at Pep Boys which was a big deal back then, because all the other parts store we knew of were mom and pops, or mom and pop with a Napa or Western Auto sign. The only option I had at Pep Boys in Syntec was an odd weight of 15W 40, which is normal in the trucking world, but not in passenger cars.
The jugs of oil started coming out in the mid 90's and they were gallons at first. So you bought a gallon plus 1 quart, because nothing used 4 quarts then that you would be caught driving, then they wised up and made the 5 quart bottle. The 5qt bottle hit the spot, unless you had a Ford that wanted 6 plus quarts.
I started driving in the mid 80's, no idea what oil was used by my older brother and dad that did the oil changes. I want to say Castrol, but not positive.
I still remember in the late 80's buying Bel-Ray oil for my motorcycle (Honda VFR 500) that was recommended by my motorcycle mechanic.
I also remember in the mid 90's paying Jiffy Lube (yes, I know, I know
) like $50 for a synthetic oil change (I think Mobil 1) in my wifes S-10 Blazer (and still doing 3000 mile oil changes with it
).
When I started doing my own oil changes, I started with Pennzoil dino oil, but since coming to this site (in 2004) I use whatever is on sale.
I still remember in the late 80's buying Bel-Ray oil for my motorcycle (Honda VFR 500) that was recommended by my motorcycle mechanic.
I also remember in the mid 90's paying Jiffy Lube (yes, I know, I know
When I started doing my own oil changes, I started with Pennzoil dino oil, but since coming to this site (in 2004) I use whatever is on sale.
I remember my dad pouring Pennzoil Multi-Vis 10-40 into a old Cressida, and Castrol 20-50 into a Mercedes 420SEL. Now that I maintain their cars for the exception of Chevron/Mobil/Valvoline, I use PP/PYB. The apple doesn't fall far from the tree.
Originally Posted By: tig1
In 1965 I bought a 64 Plymouth Valiant slant 6 with 13000K. I used QS and changed oil every 2K.
At 50K I pulled the valve cover to adjust the tappets(solid lifters). Sludge was so bad I had to scoop it out. I then changed to Valvoline and never had that problem again. Penz and QS was well known at that time for sludgeing problems. With that said, both companies improved their oils, and produce a fine product today.
That's consistent with my experience in the 80s in my 1981 Mazda, although I didn't use the QS 10W-40 long enough for sludge to get that deep. I was warned, didn't believe the warning ...
In 1965 I bought a 64 Plymouth Valiant slant 6 with 13000K. I used QS and changed oil every 2K.
At 50K I pulled the valve cover to adjust the tappets(solid lifters). Sludge was so bad I had to scoop it out. I then changed to Valvoline and never had that problem again. Penz and QS was well known at that time for sludgeing problems. With that said, both companies improved their oils, and produce a fine product today.
That's consistent with my experience in the 80s in my 1981 Mazda, although I didn't use the QS 10W-40 long enough for sludge to get that deep. I was warned, didn't believe the warning ...
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