A car that's been run on conventional all that time(since 1993) and you want to switch to a full syn is inviting bad things to happen most likely.
Running full sythetic in a classic car?
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Originally Posted By: SatinSilver
A car that's been run on conventional all that time(since 1993) and you want to switch to a full syn is inviting bad things to happen most likely.
Bad things. Well that is a valid reason for sure.
A car that's been run on conventional all that time(since 1993) and you want to switch to a full syn is inviting bad things to happen most likely.
Bad things. Well that is a valid reason for sure.
Originally Posted By: kschachn
Originally Posted By: SatinSilver
A car that's been run on conventional all that time(since 1993) and you want to switch to a full syn is inviting bad things to happen most likely.
Bad things. Well that is a valid reason for sure.
Gosh, kschachn, we surely don't want to see bad things happen with our engines!
In my experience, switching to synthetic oil in old an engine that has never seen it before causes no problems.
If I were the OP I wouldn't hesitate to try it if it made any economic sense. In his case, I don't think that it would.
Early PAO basestock oils could cause leaks because they lacked adequate seal conditioning additives. This hasn't been a problem in decades.
I'm also not sure where the notion that synthetic oils clean better came from, although there may be some truth in that notion where ester basestocks are used. Detergency is mainly a matter of the add pack used and oils are intended to clean up after themselves more than they are to clean up existing deposits, although they can do that as well over time.
Like you, I'm finding it hard to see any reason that switching any engine to a syn oil would be any sort of risk.
Originally Posted By: SatinSilver
A car that's been run on conventional all that time(since 1993) and you want to switch to a full syn is inviting bad things to happen most likely.
Bad things. Well that is a valid reason for sure.
Gosh, kschachn, we surely don't want to see bad things happen with our engines!
In my experience, switching to synthetic oil in old an engine that has never seen it before causes no problems.
If I were the OP I wouldn't hesitate to try it if it made any economic sense. In his case, I don't think that it would.
Early PAO basestock oils could cause leaks because they lacked adequate seal conditioning additives. This hasn't been a problem in decades.
I'm also not sure where the notion that synthetic oils clean better came from, although there may be some truth in that notion where ester basestocks are used. Detergency is mainly a matter of the add pack used and oils are intended to clean up after themselves more than they are to clean up existing deposits, although they can do that as well over time.
Like you, I'm finding it hard to see any reason that switching any engine to a syn oil would be any sort of risk.
I don't think leaks would be irreversible. M1 TDT made my 79 pontiac leak massively from the rear main. I went back to a dino 20w 50 and it quit leaking completely. I was floored.
Back in the late '90s I had a new motorcycle and an old early '80s car. I ran castrol Edge 10W-60 full synthetic in the bike and castrol GTX 20W-50 mineral oil in the car.
The bike only needed about 4 L for an oil change, and I always cracked a fresh 5L jug for the bike. I stored up all the extra litres of synthetic and every 4th or 5th oil change on my car, I gave it a sump of synthetic 10W-60 instead of the usual 20W-50 mineral.
There was absolutely no problem going back and forth between synthetic & mineral on my old 80s car. I was the second or third owner of the car, and I feel confident that it lived on mineral oil only before I got it. Again, no leaks and no consumption when I switched to the synthetic, and no problem when it went back to the mineral for the next few OCI.
Did, I notice any difference? Yes, on the synthetic the car started smoother and with less noise in winter, plus the oil stay a lot cleaner looking for longer with the synthetic. I would have run the car on synthetic 100% of the time, except the car was a bit of a beater and I couldn't justify the extra cost of the synthetic, no other reason.
The bike only needed about 4 L for an oil change, and I always cracked a fresh 5L jug for the bike. I stored up all the extra litres of synthetic and every 4th or 5th oil change on my car, I gave it a sump of synthetic 10W-60 instead of the usual 20W-50 mineral.
There was absolutely no problem going back and forth between synthetic & mineral on my old 80s car. I was the second or third owner of the car, and I feel confident that it lived on mineral oil only before I got it. Again, no leaks and no consumption when I switched to the synthetic, and no problem when it went back to the mineral for the next few OCI.
Did, I notice any difference? Yes, on the synthetic the car started smoother and with less noise in winter, plus the oil stay a lot cleaner looking for longer with the synthetic. I would have run the car on synthetic 100% of the time, except the car was a bit of a beater and I couldn't justify the extra cost of the synthetic, no other reason.
VR1 10w60 syn-blend is a oil i'd love to try, it's mostly used by racers but i can't see why i'd have a problem using it
Originally Posted By: FordCapriDriver
VR1 10w60 syn-blend is a oil i'd love to try, it's mostly used by racers but i can't see why i'd have a problem using it
All the oils you have listed are excellent.
Valvoline VR1 20w50 Mineral
Valvoline VR1 10w60 Syn-blend
Castrol Power 1 15w50
Mobil 1 15w50
I would pick the least expensive. But I do have a soft spot for a good 10W-60, and I do like semi-synthetics in older cars, so yes give the VR1 syn-blend a go if you like the idea of it.
I recall from previous conversations that the European VR-1 oils are all API rated and suitable for road use, so you shouldn't have a problem.
VR1 10w60 syn-blend is a oil i'd love to try, it's mostly used by racers but i can't see why i'd have a problem using it
All the oils you have listed are excellent.
Valvoline VR1 20w50 Mineral
Valvoline VR1 10w60 Syn-blend
Castrol Power 1 15w50
Mobil 1 15w50
I would pick the least expensive. But I do have a soft spot for a good 10W-60, and I do like semi-synthetics in older cars, so yes give the VR1 syn-blend a go if you like the idea of it.
I recall from previous conversations that the European VR-1 oils are all API rated and suitable for road use, so you shouldn't have a problem.
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Originally Posted By: FordCapriDriver
VR1 10w60 syn-blend is a oil i'd love to try, it's mostly used by racers but i can't see why i'd have a problem using it
If I were you ,I would've given VR1 10W60 syn blend a try, and see if it helps in cleaning up the gunks.
VR1 10w60 syn-blend is a oil i'd love to try, it's mostly used by racers but i can't see why i'd have a problem using it
If I were you ,I would've given VR1 10W60 syn blend a try, and see if it helps in cleaning up the gunks.
Seals and gaskets cause leaks - they either seal or they don't.
Originally Posted By: turtlevette
I don't think leaks would be irreversible. M1 TDT made my 79 pontiac leak massively from the rear main. I went back to a dino 20w 50 and it quit leaking completely. I was floored.
I had the same experience in my 1996 Honda Civic 10 years ago. I was the second owner, and got the car with 60,000 miles. After a year of ownership I decided I'd try a full synth oil. I put in Mag1 5W-30 and after a few days noticed drops of engine oil on my garage floor. Rear main oil seal leak. So I sucked out as much oil as I could through the dipstick tube with a pump (got 3 liters out) and replaced with 3 liters Mag1 15W-40 dino oil and the leak went away. Susequent fills with Mag1 5W-30 dino oil were also leak free.
I don't think leaks would be irreversible. M1 TDT made my 79 pontiac leak massively from the rear main. I went back to a dino 20w 50 and it quit leaking completely. I was floored.
I had the same experience in my 1996 Honda Civic 10 years ago. I was the second owner, and got the car with 60,000 miles. After a year of ownership I decided I'd try a full synth oil. I put in Mag1 5W-30 and after a few days noticed drops of engine oil on my garage floor. Rear main oil seal leak. So I sucked out as much oil as I could through the dipstick tube with a pump (got 3 liters out) and replaced with 3 liters Mag1 15W-40 dino oil and the leak went away. Susequent fills with Mag1 5W-30 dino oil were also leak free.
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i've run a 10w40 syn-blend for 20 years before switching to a 20w50 Mineral oil last September and it didn't leak a drop on the syn-blend
If you have Valvoline MaxLife 5W-40 available, that would be great in this application...
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Why bother. just run any brand name 10w30 and change it often.
Lol my engine burned oil and didn't sound very good on 10w40 i'm not going to put in a 10w30 that'd be dumb
I have used synthetics, mostly Mobil1 15w-50 or their M/C oils, in my old vehicles for 20+ years with no problems. Admittedly they all leak to some extent, but no more than expected given what they are.
Just be sure that whatever syn you choose has the appropriate additive levels for your application.
Just be sure that whatever syn you choose has the appropriate additive levels for your application.
https://mobiloil.com/en/motor-oils/mobil-1/mobil-1-high-mileage
I run this in my 1969 GTO. 10w40. The engine is a low mileage 1973 455. The shortblock is just as mother Pontiac put it together in 1973, short of me resealing the oil pan with a BOP one piece gasket when I put the rest of the engine together 4 years ago. I added lightly ported 6X-8 heads to bring the comp up to 9.25/9.5-1 and a small hyd roller cam (230/236 @ .050) with Crower solid roller lifters (tight lashed @ .006 cold). Yes, it does drip a drop or two from the 30+ year old rope rear main seal but I've been around Pontiac's a long time and they ALL do that. After 10,000 plus miles the rest of it's dry. I did use modern gaskets when I put it together.
I run this in my 1969 GTO. 10w40. The engine is a low mileage 1973 455. The shortblock is just as mother Pontiac put it together in 1973, short of me resealing the oil pan with a BOP one piece gasket when I put the rest of the engine together 4 years ago. I added lightly ported 6X-8 heads to bring the comp up to 9.25/9.5-1 and a small hyd roller cam (230/236 @ .050) with Crower solid roller lifters (tight lashed @ .006 cold). Yes, it does drip a drop or two from the 30+ year old rope rear main seal but I've been around Pontiac's a long time and they ALL do that. After 10,000 plus miles the rest of it's dry. I did use modern gaskets when I put it together.
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Originally Posted By: kschachn
Originally Posted By: SatinSilver
A car that's been run on conventional all that time(since 1993) and you want to switch to a full syn is inviting bad things to happen most likely.
Bad things. Well that is a valid reason for sure.
Real science there.
Originally Posted By: SatinSilver
A car that's been run on conventional all that time(since 1993) and you want to switch to a full syn is inviting bad things to happen most likely.
Bad things. Well that is a valid reason for sure.
Real science there.
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