OK so I have a 2001 blazer 4x4. It developed a minor oil leak a few months back that has turned into a MAJOR oil leak (5qts. in 50 miles). Now this is where it gets interesting it only leaks when you put it in gear. It will set there all day in park and never leak a drop. Put it in drive at an idle and it starts dumping oil. I know its not the rear main because the bell housing is dry inside. It runs down from the passenger side of the motor somewhere near the top. I went to the top and couldnt find any oil. I am stumped can someone please tell me what it back there that could be leaking? I would think if it were an intake gasket it would leak all the time. HELP!

 

Ok,run it up to the car wash,pressure wash the underside really good. Start it up,with ebrake on and have someone on the brakes and look underneath for the leak. its either the valve cover gasket,oil sensor unit or oil cooler lines/adapter. It may not be leaking from passenger side,oil slings everywhere.

 

if it was the oil cooler lines, wouldent it be leaking on the drivers side?

 

richie richie richie.

 

yes it would

 

Clean off the engine and undercarriage as best as possible. When dry, park over a large piece of cardboard and let the engine idle up to temperature. Check for an spots of oil on the cardboard. It may help you get a more direct line of sight on where the leak is at. If it doesnt leak while idling in park, put it in gear while holding the brakes for a couple of minutes. You really need to get a fix on what size the oil is leaking from so that you can pinpoint it. Cleaning the engine and starting from scratch is the best way to do it in a one man show.

 

OK so turns out it was the oil pressure sender that was leaking. It is still a mystery why it only leaked when it was in gear. Thanks for all your help

 

hey, listen here, I never read all of what you say...... LMAO