Did I mess up my brake job?

Question

2017 Nissan Altima SR 2.5L

I replaced brake pads less than a month ago because I was hearing a grinding noise in the rear. I was shocked to see that the pads had approx half life left in them. Went ahead and put new pads on. Since then, I've had terrible vibration when braking and not braking.

Fast forward to today. I replaced the rotors today because I knew it was time. I did not clean the rotors before install as I've never done before and had no issues in past. All vibration is gone now. I drove 45 minutes home after install and noticed when coming to a stop, that very last second before you come to a full stop, the pedal pulsated a little bit and seemed to require a little extra force to make the car want to fully stop without letting the car roll forward a few more feet than I wanted it to. I hope I explained that in a way that makes sense. The road that goes to my house is a little downhill, so I'm pretty much riding the brakes for a minute and then I turn into my driveway. I pulled in my drive and shut the car off. I opened the door and immediately smell burning. Both sides on the front are smoking!!

I've done some research and noticed that it is somewhat normal to see this, but I've never had this happen before so I'm a little concerned. Pictures below. The front doesn't look like they've been used at all. On the back, you can clearly tell they've been used.

I guess my questions are:

1. Is the burning/smoking normal?

2. Is the wear on the rear rotors normal for a 45 minute drive on the new rotors?

3. Should I be concerned that there is no evident wear on the front but there is on the rear?

Front https://pasteboard.co/JX4nEuTH.jpg

Rear - https://pasteboard.co/JX4o5dV.jpg

Answer 1

I've had rotors smoke on the first real usage after install many times with ceramic brake pads. This is NOT abnormal ... unnerving, but not abnormal. I don't know if the pads were ceramic, but there you go. If the smoking continues every time you drive the car, there's an issue. If you don't see it anymore, then it shouldn't be a problem. The reason for the smoke is the brake pads use a binding agent (ie: glue) to hold the material together. On the first major heating cycle, this glue is heated and cured. It is very normal for it to release some smoke in the process. It's usually not a lot of smoke, but enough to be noticeable.

NOT cleaning your rotors during install is a complete faux pas ... this is really bad practice, because the rotors will most likely have a coating to prevent rust on them. This coating will contaminate the pads and most likely cause issues. ALWAYS clean rotors during installation. To do otherwise is completely laziness. A professional would clean them, you should too. To leave it on the rotors will affect braking ability and longevity ... negatively.

As far as the rear rotors go, while there is some striping on the face, it doesn't mean it is out of the ordinary. You don't show how deep the scoring goes. If you've used the rotors (ie: have braked with them installed), you can expect some kind of wear. I don't see as how the difference between the front/rear rotors would be indicative of a problem, other than if the lack of cleaning the rotor initially caused this to happen.

Another thing to ensure upon first use is to bed the brakes properly. Since you didn't clean the rotors during installation, this process will most likely NOT have been done correctly (even if you've done it). My suggestion is to get a new set of brake pads, thoroughly clean the rotors, then install the new pads and bed them as should have been done in the first place. This is the only way to ensure you're getting full stopping ability as well as longevity out of the brakes. Safety has to come first.