I have a 2000 Ford Explorer XLT 4X4 with a 4.0. It was overheating and the mechanic said my drivers side head gasket or head was bad so I had it replaced. I get the car back and the same thing well that head was warped so replaced the head again. I get the car back and still overheating now it it the passengers side head so they replaced it. I get the car back and about 3 weeks the oil light came on, the oil was 2 1/2 quarts low so took back to the mechanic and he did a pressure test and a compression test and put on a pcv valve and I have had it back 2 weeks and had to put a quart of oil in it. Do you have any ideas?
unless you pulled over immediately and shut the engine off when it overheated the engine is likely junk now.
if you continued to motor on just like 98% of drivers do then the overheating has likely cooked the piston rings, glazed the cylinder walls, seized rings in the ring lands, cook valve seals, etc.
there’s a lot of unknowns here; especially in regards to this constant replacement of cyl. heads. have they not ever heard of surfacing the heads or were they too far gone to cure?
exactly what compression readings were given? this could determine whether you should throw in the towel here.
the car was pulled over and turned off immediately. I was told the compression reading was perfect.
I fear the repeated overheating has done all the things OK4450 said in his post.
A compression test will check the compression rings and cylinders, but ont the oil rings. Even if the compression test were okay, the oil rings are likely shot. Repeated excess heat can eliminate the spring tension of them against the cylinder walls, making them ineffective. I suspect that’s where your oil is going.
They’ve removed and worked on the heads and headgaskets, but I think it’s time to either consider a boneyard engine or a rebuilt long block.
Sorry. The mechanic should have warned you of this possibility.