most likely reason for burning oil

[RavoHimself]

its not really a huge deal. but about every month i need to add a quart of oil. what would be a few main causes i could look into

 

[skyway0018746]

valve seals, worn pistion rings, check your pcv valve.

 

[gjm4l]

^bingo. Check PCV valve, check compression(for bad rings), idk how to check for valve seals, I'd go that if I couldn't figure out anything else but thats just me. A way to narrow it down is do you have blue smoke on start up or as it runs? Just on startup could be valve seals, as it runs could be rings, possibly valve seals. Clean up the engine really well and see if you can see an oil leak start to appear after driving it a few times. Valve covers and rear mains are common. Or you could get fancy and use some dye to find the leaks

 

[RavoHimself]

no smoke at all. i wouldnt doubt it though if it was rings because the PO was an idiot and should have his license taken away. he beat the engine to crap

 

[gjm4l]

Gotcha. You should have a reliable friend follow you one day(or you follow him) but it's sounding like a failed gasket so time to get out the degreaser and detail that engine bay!

 

[skyway0018746]

dont know how many miles you have but the po on my truck beat mine bad too... broke all the planitary gears in the transmission. and i now have 160k on it and does not burn anything, but it leaks pretty bad.

 

[kimcrwbr1]

Yea give it a thorough diagnostic. Run some seafoam through it to clear any carbon buildup. Do a compression test and put a vacuum guage on it will give you an idea on the overall health of the engine. If you are burning oil your cat can be destroyed fairly quickly. A complete tune up including wires and PCV ideal numbers should be within 5% between cylinders on compression and the vacuum should be around 19hg and steady at an idle. There is no way to test or clean the PCV just get a new one.

 

[kimcrwbr1]

http://www.therangerstation.com/Magazine/Summer2003/VacuumLeaks.htm

 

[RavoHimself]

well im almost certain its not anything with the heads or intake or plugs or wires because all of that is brand new. i have a compression tester so i can do that. also whats the pcv thing

 

[gjm4l]

PCV is pressure control valve. It's basically a valve in the crankcase vent system that allows pressure to vent without oil transfer. If it goes bad it can allow oil to bypass it, hence using oil. Since the system vents into the intake tract (at the TB usually) you won't see oil everywhere but it could also cause blue smoke. Idk where it connects to the intake on a 4.0 but usually if you take off the intake tube flip the butterfly open on the TB look in and it's wet with oil you know PCV is bad. But they're cheap and super easy to install so might as well replace it if you haven't. Looks like the threads full of good ideas to start some diag so good luck and let us know what you find!

 

[chilsam]

pcv

I thought it stood for "POSITIVE CRANKCASE VENTILATION"?

 

[gjm4l]

chilsam you could be right its been a while since I've needed to know more than what it does lol. I think my description of operation is a little off too. The point of the check valve is to allow positive pressure out into the intake system, but prevents pressure from from being forced back into the crankcase from the intake. It goes to the intake for emissions, why we don't just have filters on the valve cover anymore, thanks EPA. Now on the OP issue, thinking about it for a day, worn piston rings will allow blowby causing excessive pressure in the crankcase forcing oil through the pcv system causing oil to be in the intake lol. So new PCV valve and compression test as first steps.

 

[xentris02]

could be the lower intake gasket mine burned the same amount because of that. i hear its a common problem with the 93 and 94

 

[kimcrwbr1]

could be the lower intake gasket mine burned the same amount because of that. i hear its a common problem with the 93 and 94

That makes sense I would imagine the plugs on the affected cylinders would show signs of oil also and the compression would be slightly higher also. Once you get the oil thing fixed you may need to change the cat/s they are likely toast.