I have a 97 F150 with with 180,000 miles. Noticed it was a little sluggish the last couple days so was checking things out and I had to add 3 quarts of oil. I check the oil about every two weeks. I usually add a little. after that did a visual inspection and I have no drips or puddles on the garage floor. I do not notice any burning when starting it either. I change the oil on a regular basis so this is a new problem. looking for advice on something to look for, or has my motors life come to an end!!!!!!
Thanks

 

Put a new Motorcraft PCV valve in it and see if that helps, if it hasn't already been done.