Vintage Mustang Forums banner
  • Hey everyone! Enter your ride HERE to be a part of this month's Ride of the Month Challenge!

1 - 7 of 7 Posts

·
Registered
Joined
·
910 Posts
Discussion Starter · #1 ·
After I broke in my new motor, I switched to mobile 1 5w30. Now I have oil seaping from various areas of the engine, mostly from the front seal area. A nice and slimy mess. I have heard that synthetic oils will do this, but I didnt believe it. Now I am ready to give up and run a regular grade of oil. Perhaps even switching to 10w30.
What should I run? It gets pretty cool here in the fall, to keep in mind.
By the way its a 351 cleveland if it matters.

Thanks....Kevin
 

·
Registered
Joined
·
5,368 Posts
That stuff is so slippery, seems to always find a place to leak. I got tired of it and went back to old school oil. 10-30 should be fine.
 
G

·
Once the gaskets get saturated, it will stop leaking. Stick with the synthetic for a few thousand miles, and you will be glad you did.
 

·
Registered
Joined
·
3,220 Posts
Go to a synthetic blend. It will give you the best of both worlds. Synthetics don't cause leaks, they just find the holes easier...
 

·
Registered
Joined
·
4,193 Posts
I too had significant leaks when I switched to synthetic (Mobil One 10/30). Luckily there were only on the bottom half and easy to overlook. I put up with it for a couple months, and they disappeared over night. No leaks anywhere – not even any seepage. The belly of my engine is as dry as a bone!

Give it some time. Odds are yours will stop as well. Good luck!
 

·
Registered
Joined
·
3,971 Posts
I run mobil 1 in my 1970 351C and had a little seepage in the rear main and the front seal for about a year or two. Don't leak anymore. I'll tell you what if you tear that engine down it will be like the day you assembled it. Even after 12 years it's still looks just like the day I put it together. The mobile 1 doesn't break down and for some reason a clevelands lifters like to rattle and they don't now.
 
1 - 7 of 7 Posts
Top