Oil Question for 1969 Model
Thread Starter
Burning Brakes
Joined: Jul 2008
Posts: 888
Likes: 50
From: Oklahoma City Oklahoma
Oil Question for 1969 Model
I've read through the permanent posts and still have an oil question. What would be the preffered viscosity or weight for a 1969 350HP 350 CI 4 speed car that seems to be pretty much stock. I’ve had the car about 6 months. Oil looks great but prior owner did not have any further info.
The car is a weekend driver in Oklahoma. The C3 had such a long production life oil recommendations and technologies had to have changed a bunch. My search feature does not work so I had to give this a shot. Thanks...
The car is a weekend driver in Oklahoma. The C3 had such a long production life oil recommendations and technologies had to have changed a bunch. My search feature does not work so I had to give this a shot. Thanks...
Le Mans Master
Joined: Oct 2010
Posts: 6,937
Likes: 848
From: melbourne florida
2023 C3 of the Year Finalist - Modified
I live in Florida and I run 20w50 synthetic year round.no doubt some will chime in that you should never ever use that oil. I simply will reply with my word of the month "HOGWASH".
Burning Brakes
Joined: Apr 2008
Posts: 1,222
Likes: 93
From: shelbyville West Michigan
I use 10w30 in my climate. used 20w50 once in A 350 Monte carlo one winter when I was a teen and destroyed my lifters on a low mileage engine...I know people use it, but I don't care for oil that thick...remember it's a balance of pressure and flow(volume). too little of one or the other can be a problem...
Race Director
Joined: Sep 1999
Posts: 11,361
Likes: 383
From: Plano TX
In OK a 10W-30, 10W-40 or 15W-40 would all work well. You could start with a 10W-30 and see how you like the idle oil pressure and oil consumption. If it's fine, stick with it, otherwise start moving up in viscosity.
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
What? No mention of ZDDP guys? 
OP, You need to determine if you have a flat tappet or roller cam seeing you don't know much about your engine as you aren't the original owner. 10W-30 is fine but whatever brand you intend to buy, google search it first to determine the amount of ZDDP in the oil. Lots of info (and lots of controversy over whether its needed) on this in the forum here and on the internet. Then you also need to decide if you want to use synthetic oil. You do not need synthetic for your engine but it's an option.
OP, You need to determine if you have a flat tappet or roller cam seeing you don't know much about your engine as you aren't the original owner. 10W-30 is fine but whatever brand you intend to buy, google search it first to determine the amount of ZDDP in the oil. Lots of info (and lots of controversy over whether its needed) on this in the forum here and on the internet. Then you also need to decide if you want to use synthetic oil. You do not need synthetic for your engine but it's an option.
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Verdad Gallardo
Pro
Joined: May 2013
Posts: 672
Likes: 31
From: Rapid City South Dakota
Viscosity requirements are largely ambient temperature dependent. I doubt it gets very cold in Oklahoma city, any mentioned will be fine. I would not use 5w20, however.
BTW the "W" in the oil viscosity stands for winter, not weight. This is to be used to compare viscosities of oils for the lowest recommended ambient temperatures the engine will encounter. There are charts to help you find the oil best suited to your climate.
BTW the "W" in the oil viscosity stands for winter, not weight. This is to be used to compare viscosities of oils for the lowest recommended ambient temperatures the engine will encounter. There are charts to help you find the oil best suited to your climate.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
ALSO...keep in mind the oil change interval. Some oils will have a 3000mile/6 month change interval...while if you go with some synthetics ( I use AMSOIL Z-ROD 10w30)...you can go a lot more miles and have your oil change be a year. Do the math...if you are concerned on the cost...and include your filter. Then make a decision.
DUB
DUB
Pro
Joined: May 2013
Posts: 672
Likes: 31
From: Rapid City South Dakota
ALSO...keep in mind the oil change interval. Some oils will have a 3000mile/6 month change interval...while if you go with some synthetics ( I use AMSOIL Z-ROD 10w30)...you can go a lot more miles and have your oil change be a year. Do the math...if you are concerned on the cost...and include your filter. Then make a decision.
DUB
DUB