97 blazer 4.3L, 4x4 electric. First I overfilled it about 2 or 3 quarts. I didn't realized that until smoke started coming from passenger side hood. I emptied the oil pan completely then refilled the motor with the right amount and also replaced the valve cover gaskets and 3 circle gaskets where the 3 bolts go through to hold down the valve cover. I ran the truck, and at first, everything was fine. The gas pedal, power would respond great. After 10 minutes driving 10mph or so, you hear a loud squeaking noise like if a new belt was needed, but I have just replace it with a gates belt about 50.00 bucks. Gradually, the noise gets tougher and louder and heavier, grinder sound even more when you release the gas pedal and tends to quite a little when you hit the gas pedal. Thats right, as I approach the stop sign, I let go the gas pedal and you hear very loud grinding increase and as I step on the gas pedal to take off the grinding sort of quiets down a little. Eventually then smoke comes from the passenger side value cover..somewhere in the back, behind the motor, because the cover looks clean all around. The truck loses power and doesn't go as fast nor respond as quickly as when hitting the gas pedal. I can see that the battery is very low almost empty and truck is barely moving. Someone told me to change the transmission module but I got no idea where that is located. My truck has 16bold transmission oil pan and I read somewhere that these pans don't have a transmission module. WHERE COULD BE THE LEAK BE COMING FROM?? IS THERE A GASKET WHICH GOES BETWEEN THE MOTOR AND TRANSMISSION?? I WOULD LIKE TO TAKLE OF THING AT A TIME.:rolleyes:

I found out that the battery was training quickly since I forgot to plug in the cable into the alternator. NOW, to find the Mysterious Oil Leak if hard. I double checked and double looked at the blue gasket around the valve covers and it's top 3 holes..ALL CLEAN, NO LEAKS Through Here. Somewhere in the back comes the leak?? Where??

i would guess that a good place to start would be a compression test. does it leak when running, sitting (off), or both?