Throughout December 2015, I noticed several threads in which Jim or someone he typically agrees with made a point: if you can't get five good reps on your 5/3/1 day, you're using too much weight.
Maybe everyone else knew this and, despite having three degrees that basically prepared me to be a master reader, I missed it, but I didn't make that connection. I assumed that on the 5/3/1 day, you aiming for one rep. If you got that one rep, you could move on up.
Whatever the case, I swallowed some pride (some bourbon, too... it was the holidays) and went back over my Personal Records for each of the four lifts. I chose the highest weight at which I had done a minimum of five reps. So, for instance, if had benched 250 pounds five times and had done 255x4, 250 was my new Training Max.
I'm on week three, so this is my 5/3/1 week. I've been really happy with the change, so far. I did 225x10 on bench (the old PR was 225x9) earlier today. On top of that, the lower weight has allowed me to work on bar speed, technique, and staying strong when I get into the higher rep range.
Anyway, if you've been stalling and even the 5 Foward/3 Back doesn't fix it, try resetting your TM to a weight you KNOW you can hit five good, hard times. One of the best parts of this program is that it seems like every single obstacle or issue or goal has an answer.