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Anyone have pics of underside of valve cover?

24K views 27 replies 9 participants last post by  lnxpeng 
You say it's the exhaust side (connects resonator to valve cover exhaust side) that's restricted, but cart7881 says it's the intake side (connects valve cover intake side to intake manifold) that's restricted with an orifice.

At least I think we have the direction correct, judging from everyone's posts (thanks!). I'm assuming the orifice side will be the most likely to become clogged and cause problems, so I'm curious to know which side is restricted. I'm using about a quart every 7000 miles, and I think most of it is deposited on the back of the motor, just by looking at it. That's not bad for a motor with 170k miles on it, I think.
That just sounds like a rear main seal leak to me. I would replace seals and change my oil every 5k instead of 7k especially on high mileage trucks, but that's just my personal preference. catch can wouldn't hurt either, I have been wanting to do this.
 
It might be. I should say I meant the oil is on the top rear, on the valve cover (and I have a decent film in my resonator box). I cleaned the TB two years ago and it still looks pretty good, so it's not excessive. My plugs don't look great but I had the MAP sensor go bad about a year ago and I didn't diagnose it properly (I assumed it was the head issue, stupid to not investigate). It's possible it could be rear main seals. Not sure I want to know what's involved in replacing them.

I want to get the catch can mounted and get the intake oil figured out before I replace plugs.
Yeah its probably not a rear main seal then, Changing the seal is easy when the transmission is out lol. Word of advice, if you ever have any tranny work done, or a shop needs to pull it for any reason. Ask them to change the rear seal while its out! They will usually do it for the price of the seal (maybe$20 max) or for free. Its always a good idea to change it if you have that chance.

I would wait on changing plugs until the other stuff is taken care of as well. You say the leak is on the top rear, so maybe you can get away with just changing the valve cover gasket? you probably have already done that if you pulled the cover though.. best of luck I hate leaks.
 
aww man ive always wanted one of those! for uhh... research purposes..

as far as the rockers and lifters, without removing the cam...no clue.
 
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