engine use alot of oil 2qt 300 miles

[1Byounkin]

I have a 1991 Explorer 4X4 all standard. The truck started using oil alot lately. About 1.5 - 2 qts to a tank full (300miles). I'm using 20w-50 oil. The engine doesn't smoke, but you can smell it sitting at idle. I didn't think there is any new links. I have replaced the valve cover gaskets and intank gasket. What is an easy fix without disassembling the motor, as in replacing rings. Gaskets are no trouble.

This is getting aggravating to add oil all the time.

thanks

 

[jtb1689]

If you want to stick with just a gasket fix (although it may not be the issue, but I'm sure you are aware of this) your best bet would be to check and see where oil is leaking from. On mine it was the timing cover gasket (though I was only about a quart or so every 3000 miles). I would go underneath spray some brake cleaner or something all over the place, wipe the oil pan, heads, bottom of the block, everything you can get to wipe off as clean as you can. Then check later and see where it's oily again. I'm sure some others will have some ideas if you give it a little bit of time as well.

Remember though, that much oil, quite possibly isn't just a gasket leak. Check your coolant for oil and your oil for coolant. And I'm not sure about that 20W-50, I can't say from experience but I've heard thick oil like that can really hurt your pump over time. And decrease mileage.

Good luck!

 

[1Byounkin]

I know that there is no oil in the coolant or coolant in the oil. Oil I use differs from time to time 10w-30 20w-50 and so on. Is high mileage oil better, even with links. Had to fix the Cat because I was told the engine has been burning oil and made that clog up. Well the engine runs at 3000 rpms at 60 mph as I travel every day to school. I'm planning on cleaning under the truck to check for links. Could the valve seals be bad?

thanks

 

[jtb1689]

High mileage oil's advantages is an age old debate. Some swear by it's better conditioning of gaskets and will vouch for it stopping some of their leaks. Others will say it's nothing but a sales gimmick. Personally I do use it as it doesn't personally cost me anymore than regular oils. Even still though, if you are leaking 2 quarts in 300 miles I think you may be looking at a bigger fix than just changing oil types.

 

[1Byounkin]

This around the time I change oil, but I would like to fix this problem before putting good oil. Maybe its telling me to change oil. Some people say to use MAX LIFE oil. The exhaust pipe has a gummy black stuff in the pipe. Could this be the bunt oil? No smoke ever comes out, unless at an angle.

 

[rhauf]

High mileage oil's advantages is an age old debate. Some swear by it's better conditioning of gaskets and will vouch for it stopping some of their leaks. Others will say it's nothing but a sales gimmick. Personally I do use it as it doesn't personally cost me anymore than regular oils. Even still though, if you are leaking 2 quarts in 300 miles I think you may be looking at a bigger fix than just changing oil types.

High milage oils *will* slow and even stop leaks, and prevent blow by as well.. but its all for a short time only (maybe a year, depending on the instance), "conditioning" of gaskets and seals really just means that it makes them puff up to form a better seal.. but not long after puffing them up, they will begin to disintegrate and fail. for this reason i avoid them like a plague. it's likely that the reason you have so many leaks now is because high mileage oils have been used in the past.

since you're truck isn't blowing smoke out the exhaust, i think it's safe to say it isn't burning oil, so it must just be coming from all the leaks. if it were me i'd change all the gaskets and seals (including the timing cover seals and gaskets, and the rear main seal), and run 10w30.

 

[rhauf]

This around the time I change oil, but I would like to fix this problem before putting good oil. Maybe its telling me to change oil. Some people say to use MAX LIFE oil. The exhaust pipe has a gummy black stuff in the pipe. Could this be the bunt oil? No smoke ever comes out, unless at an angle.

ohhh i just saw this part.. maybe its an intake gasket? would a warn valve stem seal be a possibility here? need a 4.0 expert to chime in

 

[1Byounkin]

I have never used high mileage oil, just thought it might better. I usally use 10w 30. I just thought using a thicker oil would be better also. Is the timing cover and the rear main seal hard to replace? I know on GMC 1 ton you have to remove the trans. So if the engine is not "buring oil" why is there a black gummyness in the exhaust pipe?

 

[rhauf]

I have never used high mileage oil, just thought it might better. I usally use 10w 30. I just thought using a thicker oil would be better also. Is the timing cover and the rear main seal hard to replace? I know on GMC 1 ton you have to remove the trans. So if the engine is not "buring oil" why is there a black gummyness in the exhaust pipe?

well you said it doesn't smoke, and burning oil = smoking exhaust... but i also saw you said it burns oil at an angle.. or did i misread that? if this is the case then that's you're problem, an internal oil leak, probably in the intake gaskets or valve stem seals. (not warn pistons, as they don't care about angle)

 

[1Byounkin]

aYes you did read that right. My yard is a hill, if I go sideways on the then smoke would show up. Not went driving. But would some seep out though the valve seals went driving? I think I do need to remove one of the heads because I believe that I have an exhaust valve leaking. Why? I hear a skweeking sound in the pipe at idle, and when I had the pipe cut after the header to fix the Cat I could hear a skweeking in the pipe as it idled.

This might be good to do.

 

[rhauf]

If you have a burnt valve (valve not sealing) it would show up in a compression test.. maybe that would be a good thing for you to try, too.

from what i read.. might be the best idea for you to just buy a gasket kit (and head bolt kit) for you're engine, and tear it down (heads off, oil pan and other covers off etc) and put it back together with new gaskets and seals. and get a valve job done on the heads at the same time.. i dont know, its hard to say without seeing it myself.

what would you consider you're level of technical ability?

 

[Allmost 50]

what would you consider you're level of technical ability? Good question rhauf. Be careful when tightening up the various engine cover bolts. Nothing will ruin your day like a broken bolt in the block or head. You can always retorque a bolt later. If you break a bolt ???
Go ahead and change your pcv valve for a process of elimination.

 

[1Byounkin]

I can tear down the engine to the head and reface the valves myself. I have a valve grinding machine and seat refacer. "Van Norman" Hoping the repair is on the driver side
Understand about breaking bolts.
I'm just trying to find away to pen point the problem without taking too much apart.

Does anyone know about how to replace the rear main seal on a 4.0L?