1993 Jeep Cherokee V8 Four Wheel Drive Automatic 179026 miles
I recently had the transmission replaced. Now it is emitting black smoke from the exhaust pipes. I had an oil change and when the engine is just warming up or the weather is cool, the smoke does not appear. However, after the jeep has been running for a time, or if I am sitting still in hot weather then heavy smoke emits. I save space between me an other vehicles so that I can roll forward a few inches - that slows down the smoking during the movement, but it immediately returns when I come to a complete stop while the motor is running. A friend, who is not a mechanic, said I might need to get the " Rings" replaced, and that, since I am having that done, I may as well get the " Heads" replaced as well. This will cost close to $2,000. My question is, are those repairs possibly what could correct the smoking in hot weather or when the engine is hot?
That's a pretty old engine you have there. I would start by having a compression test done to see what the state of your cylinders are.
Try doing an oil change and tossing in a bottle of Lucas Heavy Duty Oil Stabilizer and see if the smoking decreases.
Piston oil rings are a common cause of burning oil, not sure why it's only happening during hot weather. If you indeed need to have your rings replaced, have your mechanic look at the head and see if it is still in good shape, if it is damaged then go ahead with the repair.