New Oil
Thread Starter
Disabled by request 8 JUN 2025
Joined: May 2019
Posts: 329
Likes: 94
From: St. Augustine, FL
New Oil
I just noticed that Castrol has a new oil out. "Castrol GTX Classic". They say it's specifically designed for older classic cars with flat tappet cams, high performance cars and cars needing PDDF zinc additive. It's available only in 20/50 weight quarts, and not for cars with catalytic converters. The industry is listening to us.
Race Director
Joined: Nov 2006
Posts: 13,143
Likes: 7,753
From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
2024 C3 of the Year Finalist- Modified
2022 C3 of the Year Finalist - Modified
Cruise-In VIII Veteran
But MOST of us with flat tappet cams have no need for cats and much need for the zinc. Here in Australia there is a good supply of 20W-50 high zinc oil. Maybe the only good thing about being here.
Melting Slicks
Joined: Sep 2016
Posts: 2,191
Likes: 955
From: Wauconda IL
I found this:
5W50 Castrol Edge with Syntec API SN, synthetic, formerly Castrol Syntec, black bottle = 75,409 psi
zinc = 1252 ppm
phos = 1197 ppm
ZDDP = 1200 ppm
https://www.autorestomod.com/oil-zddp-list.html
5W50 Castrol Edge with Syntec API SN, synthetic, formerly Castrol Syntec, black bottle = 75,409 psi
zinc = 1252 ppm
phos = 1197 ppm
ZDDP = 1200 ppm
https://www.autorestomod.com/oil-zddp-list.html
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Drifting
Joined: Aug 2017
Posts: 1,433
Likes: 351
I found this:
5W50 Castrol Edge with Syntec API SN, synthetic, formerly Castrol Syntec, black bottle = 75,409 psi
zinc = 1252 ppm
phos = 1197 ppm
ZDDP = 1200 ppm
https://www.autorestomod.com/oil-zddp-list.html
5W50 Castrol Edge with Syntec API SN, synthetic, formerly Castrol Syntec, black bottle = 75,409 psi
zinc = 1252 ppm
phos = 1197 ppm
ZDDP = 1200 ppm
https://www.autorestomod.com/oil-zddp-list.html
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,809
From: Cool Northern Michigan
The Environmental Protection Agency had a real concern about bringing back Zinc to motor oils in daily drivers. AKA common off- the-shelf oils.
Oil companies had a way around that concern by labeling the bottles to appease the Feds.
Some of the bottles were labeled:
Tractor Oil
Racing Oil
Not For Street Use.
Break-In Oil.
That lead the customer and the EPA into thinking it was a temporary use oil. And no harm from coating the inside of the converters.
Something like a catalytic converter "test pipe". No one said how long a customer could use that either.
Oil companies had a way around that concern by labeling the bottles to appease the Feds.
Some of the bottles were labeled:
Tractor Oil
Racing Oil
Not For Street Use.
Break-In Oil.
That lead the customer and the EPA into thinking it was a temporary use oil. And no harm from coating the inside of the converters.
Something like a catalytic converter "test pipe". No one said how long a customer could use that either.
1967 Pedal Car Champion
Joined: Mar 2020
Posts: 8,986
Likes: 4,143
From: US-PNW
Which is probably how they came to discover that the high zinc was causing converter failure. With the high mileage warranties (I recall 50k & 100k mile warranties) on this type of emission equipment I'm sure the auto makers were scrambling to limit replacements under warranty.
Drifting
Joined: Nov 2007
Posts: 1,695
Likes: 270
From: New York
Admitting I could be wrong, but doesn't racing oil have less detergent since it's made to be changed frequently?
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,809
From: Cool Northern Michigan
I also have been loyal to Lucas Classic. But like everything else, price has been creeping up over the last couple yrs.
My last jug (5 qt) was $34-$36 roughly.
H-m-m-m-m-. This Castrol Classic is $19.32 per jug at Amazon. There's an old saying: What's the catch?
I'm not going to try it. You try it. Let's get Mikey to try it.
My last jug (5 qt) was $34-$36 roughly.
H-m-m-m-m-. This Castrol Classic is $19.32 per jug at Amazon. There's an old saying: What's the catch?
I'm not going to try it. You try it. Let's get Mikey to try it.
Burning Brakes
Joined: Oct 2018
Posts: 1,031
Likes: 465
From: Henderson, NV
St. Jude Donor '19-'20-'21-'22
You are certainly correct about the price of Lucas Oil. Like everything else it seems, the price has jumped considerably.
I, just last week, paid $39 for a 5 qt. jug at O'Reilly.
I, just last week, paid $39 for a 5 qt. jug at O'Reilly.