JCM 9,130 #1 Posted August 13, 2020 Cleaning out the old shop, garage and basement and filled 2 30 yard dumpsters within the past 3 years and found some items. Has anyone else heard of this Arco graphite oil ? I remember trying this out because a friend of mine his Father owned an Arco service station and wanted me to try out this oil, this was around 1977 -8. I had been using Kendall 20-50 in the 396 Chevelle and was happy with it but he talked me into it. I had added Stewart- Warner oil and temp gauges and when I used that oil my pressure dropped from 50- 60 psi to-around 20 psi, back home drained it and back to the 20 - 50 kendall and pressures where back to normal. Does anyone have a logical answer to this one . The second photo is a set of Snap On test gauges that my uncle gave to me when I was around 17 or 18. Also found some chevelle parts that I just could not put in that dumpster. 3rd pic is my spare tire and rim for the Chevelle a bias ply Gillette Sprint. Changed those over to BF Goodrich radial T/A with Cragar SS rims. The SS did not have power steering and with those bias ply tires it steered hard and with the addition of Radials it felt like it had power steering. My brother in law who now owns the SS has added power steering among numerous other upgrades. 4 1 3 Share this post Link to post Share on other sites
Skwerl58 702 #2 Posted August 13, 2020 Brought back some memories. My brother had a 69 SS 396 with the factory wheels, like your spare. I painted those wheels for him and it was a lot of work. Masking off the black to paint the silver. I ended up with the car and have some pictures of it. No explanation on the oil but mine did better with the Havoline 10/40, seemed to have more power. Go figure. 1 Share this post Link to post Share on other sites
8ntruck 6,991 #3 Posted August 13, 2020 The company I just retired from made those OEM wheels. Was Motor Wheel. Probably produced in the Lansing Michigan plant. 1 Share this post Link to post Share on other sites
ZXT 2,401 #4 Posted August 13, 2020 (edited) Well, the 10w-40 is obviously quite a bit thinner than 20w-50, so that would account for the pressure difference. Was the pressure checked with it hot, cold, idling, going down the road, etc..? If you had 50-60 PSI idling hot, that's really too much. Idling hot, 20PSI doesn't sound unreasonable, especially in this heat. Only time a SBC/BBC would need 20w-50 is if it had pretty loose tolerances. General rule of thumb is 10PSI per 1,000 RPM. If you've got that or better, you're good. Edited August 13, 2020 by ZXT 1 Share this post Link to post Share on other sites
ebinmaine 67,283 #5 Posted August 13, 2020 Good stuff Jim. I remember the graphite oil but don't remember ever using it. 1 Share this post Link to post Share on other sites
JoeM 7,871 #6 Posted August 13, 2020 Remember all those things, worked in a garage as a teenager. I think my brother still has one of those timing lights. My bosses son had a 68 Hemi Road Runner, 4 speed! Took a bunch of stuff off, like the wheels, cast iron headers, cam and I more. I picked those old headers out of the trash and he gave them to me. Sold them for $250 in the late eighties to a guy in New York. Memory lane, don't blink! 1 Share this post Link to post Share on other sites
edgro 677 #7 Posted August 13, 2020 IIRC It seems like the graphite oil was black coming out of the can. So how could you tell if oil is dirty by the dipstick? That could be why it wasn't too popular 1 Share this post Link to post Share on other sites
rmaynard 15,428 #8 Posted August 13, 2020 14 hours ago, JCM said: Has anyone else heard of this Arco graphite oil ? Ahh, yes. When I was younger, let's say about 45 years ago, I was notorious for not changing the oil in my my wife's old VW. When her father did an oil change for her one time, he said that her oil was so black that he could tell that it hadn't been changed in a year or more. I was a little embarrassed and replied "I only used ARCO Graphite, it's already black when it's new". Squeaked out of that one. 3 Share this post Link to post Share on other sites