69/70Plymies
Well-Known Member
Here's the reason I need to poll you Mopar heads on oil.....
1) '70 383....About 1 1/2 yrs. ago, I finished a near-stock rebuild and did some research on the best engine oil to use. I found Joe Gibbs Break-in Oil was very popular, so I did that and also went with Joe Gibbs 10w40 Conventional Hot Rod Oil after the break-in period. Not long after the first 500 miles, the oil pan, valve covers, and inside the bell housing began leaking oil. The bell housing oil could be "migrating" oil from the oil pan, not sure. I first thought it was due to improper gasket sealing. There's about 3,000 miles on the engine, now. After discovering oil leakage in my '69 318, I'm wondering if it's the oil causing these leakage problems.
2) '69 318....I was previously using 10w30 Mobil 1 Synthetic (previous owner used this) and adding a zinc additive. About a year ago, I decided to go with Joe Gibbs 10w30 (for small block) Conventional Hot Rod Oil since my research showed this ideal for zinc levels, etc., I was using this brand in my '70 383, and I would not have to add a zinc additive to the oil. Well, I just came from the garage tonight and I have 3 oil stains on the floor from the car sitting all winter and a small puddle of oil on top of the pass. side of the K member. Never did that before. Started it up and after about 10 minutes, I noticed oil on the v-belts. Seems to be coming from the front main or the front oil pan seal. Now about this time I'm saying to myself, "What in the world did I do going with Joe Gibbs oil?" Can I return to using the Mobil 1 Synthetic or am I SOL?
I need some help evaluating if Joe Gibbs HR oil may be the type that likes to migrate through gaskets. I know some oils do this due to certain additives. Has anyone else experienced this problem. What engine oil do you fellows use in your stock-build, 46 yr. old Mopars and are happy with? Thanks for the help!
1) '70 383....About 1 1/2 yrs. ago, I finished a near-stock rebuild and did some research on the best engine oil to use. I found Joe Gibbs Break-in Oil was very popular, so I did that and also went with Joe Gibbs 10w40 Conventional Hot Rod Oil after the break-in period. Not long after the first 500 miles, the oil pan, valve covers, and inside the bell housing began leaking oil. The bell housing oil could be "migrating" oil from the oil pan, not sure. I first thought it was due to improper gasket sealing. There's about 3,000 miles on the engine, now. After discovering oil leakage in my '69 318, I'm wondering if it's the oil causing these leakage problems.
2) '69 318....I was previously using 10w30 Mobil 1 Synthetic (previous owner used this) and adding a zinc additive. About a year ago, I decided to go with Joe Gibbs 10w30 (for small block) Conventional Hot Rod Oil since my research showed this ideal for zinc levels, etc., I was using this brand in my '70 383, and I would not have to add a zinc additive to the oil. Well, I just came from the garage tonight and I have 3 oil stains on the floor from the car sitting all winter and a small puddle of oil on top of the pass. side of the K member. Never did that before. Started it up and after about 10 minutes, I noticed oil on the v-belts. Seems to be coming from the front main or the front oil pan seal. Now about this time I'm saying to myself, "What in the world did I do going with Joe Gibbs oil?" Can I return to using the Mobil 1 Synthetic or am I SOL?
I need some help evaluating if Joe Gibbs HR oil may be the type that likes to migrate through gaskets. I know some oils do this due to certain additives. Has anyone else experienced this problem. What engine oil do you fellows use in your stock-build, 46 yr. old Mopars and are happy with? Thanks for the help!
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