I usually don't touch the brisket until about four hours, and then I go check the temp. By this time with a meat thermometer. It should be around 155-160 degrees. This is around the temp where it 'stalls' or plateaus and won't get any hotter. This is where many pitmasters will wrap the brisket in paper or foil to concentrate the heat and speed things up. I have found that the taste of the foil gets into the food, so instead of plain foil, I use the thicker 9x13 foil serving trays one on top of the other.
Do this part quickly to avoid losing much heat. Lift lid, pull the brisket out with a large fork or hook and place in the serving tray. While the lid is off, check your coals and push them around to keep them burning. By this time, the fruit wood will still probably be partially burned and may still be leaning on the sides. You can stir those around a bit also. Since I am covering the brisket, I don't mind kicking up more smoke.
Pour 1/2 cup of hot apple juice or cider (use a microwave) over the brisket, and cover with the other tray on top. This will braise the brisket as it finishes cooking and make it nice and juicy. You will need to pinch the edges and probably push in the sides to get things to fit back in the smoker. Cover the lid and go on about your business. Almost there.
At about the 5 hr and 30 minute mark, you will want to keep an eye on temps. Here is when folks argue about when to remove the brisket. You want the temps around 190 and above. I like to pull the brisket when it reaches 195 degrees. All you need to do is lightly poke the brisket in a few spots, making sure the temp probe or knife easily slides into it.
The cool thing about using the foil serving trays is you simply put some oven mitts or welding gloves on, reach in and just pull the whole thing out and let sit on a heatproof surface for at least 15 minutes. I then pull the water pan out and use a cup of the juices to start gravy while the meat is resting. I also tilt the serving tray and pour some of the heavenly juices from the bottom into the gravy.
That's it! You have reached the apex. The smell in your kitchen will be incredible, and you guests will be in awe. Place the brisket on a cutting board, and starting from one end, slice into thin strips crosswise about 1/8 inch thick at a slight angle and serve. Pair this up with all the fixings of bbq, like spicy coleslaw, macaroni and cheese, and your other favorites. You should be proud of your accomplishment. To this day, I always feel amazing having cooked up a delicious brisket for the family, and it is one of the best treats around. Enjoy! If you like, making smoky gravy is easy. Add about 1/2 cup of the smoker pan juice to 1 cup beef or chicken broth, any spices you like, and thicken slowly over heat with a slurry of corn starch and water until you get your desired consistency.