I just bought a 10 year old GMC truck. The blower will operate intermittently. I am assuming the problem is not in the control knobs, etc... but instead I suspect the motor itself is worn out.

Can you give me any advice on changing the blower motor? Is it a DIY kind of job? How do I remove the plastic case so that I can get to the motor?

Thanks,
dbteeitup

It probably depends. I fixed a blower on a Toyota. What happened was as the temperature got colder, the friction mount caused the blower to slide out of it's mount and stall. I could push the motor back up and it would work for a while and did it again. There was a factory fix but the part was no longer available when I had the problem. The stalling wore the brushes.

I could pull the motor without dissassembing the dash. I was lucky. I had the entire dash out in that vehicle in the past when I installed the airconditioning system from a box.

Instead of replacing the motor, I made a bracket and visited a vacuum cleaner store and found brush material I could use. I then filed the brushes to fit and soldered it in place. The brushes were like $2.00.

If it works on high speed and not the lower speeds, the blower resistor is bad. I have to replace one in a 2000 Chevy.

It is very simple. You have a mutiposition switch that selects a resistor or no resistor and a motor. Unfortunately, the problem your describing could be any one of the above items although I might suspect brush wear.

Pretty easy job,there should be I believe about 8 5/16 or 1/4 bolts and the blower motor pops out,there is one plug in that runs the blower motor.When the blower stops and you wack it does it run again?If so the motor is shot.The motor should be on the passenger side under the dash,you don't have to rip the dash apart to get at it,pretty easy spot to get at.