Brake Issue (Yes I used the "search" function)
So I tried the search function and couldn't find an answer, but this is kind of an odd one. It started a few weeks ago as I was driving to work (which is only about 4 miles away) but as I got to the bottom of the hill my neighborhood is on, it became clearly obvious to me that my brake pedal was not returning, but if I lifted it back up to it's normal position all the brakes would release and it would be fine. This went on for a couple days and then it stopped and it seemed like everything would be fine. Well then on Monday I was on my way to work again, and this time after I pushed the brakes the initial push was fine and normal, but any subsequent pushes were hard like there was no power assist and it felt like my stopping power was reduced because I had to really stand on it and even then it was not really stopping very well. about 1.5 years ago I had my master cylinder go bad and kill my booster also, so those are both relatively fresh. I checked my fluid level and it is just below the max mark on the reservoir. I also pulled the vac check valve and that's fine too. The vac pump is making good vacuum too, and that was replaced at the same time as the booster/master cylinder. The booster holds vacuum for at least 5 hours after the truck has been sitting, so I don't think that's my problem. It's got to be something simple that I'm overlooking. Any other ideas? Also, all of these problems have been happening in colder temps, the first episode the temps were in the single digits, then it warmed up to the 30's-low 40's, and now we are in the teens with single digit overnight lows. Thanks in advance.