Beating a Dead Horse
Thread Starter
Obsessed
Joined: Apr 2019
Posts: 627
Likes: 394
From: Valencia, Spain
2025 C3 ('68-'73) of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
2019 C3 of Year Finalist (stock)
Ok this is slightly off topic concerning oil, but probably dead on concerning beating dead horses! I’ve only had my ‘73 for 2.5 months after 46 year wait, so y’all cut me some slack. These cars were built when gas was leaded and cheap. Is there anything else I should be putting in the tank besides ethanol free 93 octane? It’s a stock 350 with 4 speed. Thanks in advance!
Ok back to my original question. Should I use the Shell Rimula R4 15W 40 Ci4 E7 diesel motor oil I bought or look for a regular 10W 30 or 40 and use a Zinc additive?
Melting Slicks
Joined: Apr 2001
Posts: 3,399
Likes: 278
From: Olmsted Falls, Ohio
If you can't find out for sure about the Shell oil then you could use regular oil with a Zinc additive. That might be more expensive, but at least you would know for sure.
I used a Zinc additive with some Castrol oil until I finished the case of oil.
I used a Zinc additive with some Castrol oil until I finished the case of oil.
Pro
Joined: Jan 2001
Posts: 511
Likes: 66
From: Timnath, CO
I worked in the lubricant industry. I spoke about ten years ago with a well known diesel engine oil formulator that worked for a major lubricant additive company. He owned a big block C2 or C3 (can't remember), and said that he always used diesel engine oils in his Corvette as he considered them more robust in that application.
Thread Starter
Obsessed
Joined: Apr 2019
Posts: 627
Likes: 394
From: Valencia, Spain
2025 C3 ('68-'73) of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
2019 C3 of Year Finalist (stock)
I worked in the lubricant industry. I spoke about ten years ago with a well known diesel engine oil formulator that worked for a major lubricant additive company. He owned a big block C2 or C3 (can't remember), and said that he always used diesel engine oils in his Corvette as he considered them more robust in that application.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
The "Shell Answer Man" (1960s - 1990s) is either getting too old or is a newbie.
"Zinc? What's that? I 'll have to call you back."
"Zinc? What's that? I 'll have to call you back."
Last edited by HeadsU.P.; Feb 10, 2020 at 06:22 PM.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
Just so you know 71 was the first year of the lower compression motors (8:5:1) and made to run on unleaded.., You really don’t need the higher octane gas, your 73 should run great on regular...
Ok back to my original question. Should I use the Shell Rimula R4 15W 40 Ci4 E7 diesel motor oil I bought or look for a regular 10W 30 or 40 and use a Zinc additive?
Ok back to my original question. Should I use the Shell Rimula R4 15W 40 Ci4 E7 diesel motor oil I bought or look for a regular 10W 30 or 40 and use a Zinc additive?
-add-
the zinc & phosphorus numbers you seek are in the VOA BITOG link that's in jim2527 post #2 above
Last edited by jackson; Feb 10, 2020 at 07:57 PM.
