94 Going through oil. Help!

[mattvOR]

I recently drove to Portland (400miles one way) and about 2/3 of the way into my trip my oil light came on. So I pulled over and sure enough I had to add 2 qts. I made it the rest of the way and replaced my Pcv valve and checked oil. Everything was fine and I drove it for two weeks in Portland without going through any oil. When I finally left to come home I checked my oil here and there and it was fine till the last 200 miles then started going through oil again. 4 qts in the last 200 miles of the trip home. However I was towing my boat for that stretch. So I took it to a reputable shop when I got home as I couldn't find any leaks and no smoke from the exhaust. They said my rear main and upper pan gasket was leaking, which has always had a small leak since I've had it. I don't have anymore oil under it while it has been sitting for days than I ever have. They wanted $1000 to fix those leaks but I hate to throw money at something that's not the true cause as those leaks look the same as they did when I bought it 3 years ago. It has 163k on it, I have not done the HG yet and it still seems to run great. I drive this to and from Portland every month and have never consumed any oil on the trip until now. I did loose a little coolant also but they found a leak in my radiator at the shop and a couple more leaking hoses. They did not do a compression check either.

I have replaced the oil pump cover seal and crank seal as well as the PHH. Other than that just regular maintenance and drive. Usual oil consumption was about 1 qt every 1500 miles before the new problem.

Any advice would be great as it can't seem to find any obvious leaks or issues. Never lost oil pressure and no oil in coolant or vise versa. I have talked to a couple shops and have received all kinds of answers.

Thanks you.

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[CJF]

Four quarts in 200 miles??

That hardly even seems possible.

 

[mattvOR]

Yeah pretty crazy. But like I was saying I was towing a boat that last 200 miles.

 

[gtfour43]

Four quarts in 200 miles??

That hardly even seems possible.

Without a LOT of smoking or puddling somewhere. What grade oil u running?

 

[mattvOR]

I run 10-30 mobile 1. So a week ago I topped it off and parked it to see if there was any major loss of oil or dripping under it and checked it this morning and had the regular drip or two on the ground and still on the full line. Is it possible that when it's under pressure and running that a rear main or pan seal will go through a ton of oil and not while sitting or casual driving around town? Or you think it's time for a HG job?

 

[Brentbba]

Wouldn't you have a mess under the truck if you were loosing that much oil via the rear main or oil pan? Used to tow regularly a 4000lb trailer and never lost oil. If you aren't puffing out the tailpipe, it's got to be going somewhere!

 

[Kaveeks]

It usually takes awhile for all the oil to drain down in order to get a good reading on the dipstick. If you check it right after shutting it down, it will look like it's low.

 

[thatcabledude]

There is no way you burned 4 quarts in 200 miles. You would have looked like the mosquito man going down the highway!

Is there any smoke at start up to indicate valve seals?

 

[mattvOR]

First off I just was to say thanks for taking the time to help out a complete stranger. I sure appreciate it.

I haven't spent a whole lot of time under it as I am recovering from a broken femur! But today I got under it wiped the rear main/pan leak "collection area" an then drove to the store and home (about 10 miles) and it had a fair amount of oil collected again when I got home. However it didn't look like it was a 4qt in 200 miles leak.

I also ran my finger in the tail pipe when I first started it before leaving and it was moist. Drove it to the store and back and when I got home I did it again and it was dry and just a little sooty. Nothing crazy.

I am borrowing a oil dye kit from a guy tonight and hope to use a mirror and look in that inspection plate to see exactly where it's coming from.

This whole thing just seems inconsistent, especially being a DD and never having these problems.

 

[mattvOR]

There is no way you burned 4 quarts in 200 miles. You would have looked like the mosquito man going down the highway!

Is there any smoke at start up to indicate valve seals?

I have never noticed a significant amount of smoke upon start up. Maybe a little if it's been sitting which is not often.

 

[mattvOR]

This is how it looked when I got home.

 

[cruisercommando]

Our '93 with 335K miles has no leaks, but get it on the freeway, and you'll need to get oil every time you get gas. My wife can drive it for weeks back and forth to work where she rarely goes above 50mph, and it might use a couple quarts between 5k oil changes. We can tell it burns some oil by the residue on the back hatch. However, when we drove it from Phoenix to OKC last year (approximately 2500 miles round trip), it would easily use two quarts every 300-350 miles. I ended up buying 2.5 gallons jugs of Rotella 15-40 instead of qt bottles. Obviously 335K is a lot of miles, even for these engines. I know the valves seals are worn as well as the rings.