Mechanic Monday: Chevrolet GMT400 Blower Motor Replacement DIY

Getting the heater in your Chevrolet or GMC GMT400 to blow harder is incredibly easy.

If you have a Chevrolet pickup, Tahoe, Suburban or the GMC equivalent from the late 1980s through the 1998 model year, there is a good chance that the air conditioning and heating system doesn’t seem to blow as hard as it used to. Your first thought might be to get the truck to a shop where you can pay to have it fixed, but after watching the video above from the Jonny DIY YouTube channel, you will see that the fix is so easy that you can do it yourself. You only need one tool and even if you’ve never worked on your own vehicle before, this is a very simple project.

Tools for the Job

To replace the blower motor in your Chevrolet GMT400 truck or SUV, you will need the following tools:
7/32-inch socket
ratchet or driver handle

That’s it. You really only need one tool and a socket, and you can replace the blower motor in your 1988 through 2000 Chevy truck or SUV.

Step One- Remove the Glove Box

As the video above shows, the project begins by removing the glove box. This is done by removing the cord that keeps it from swinging open too far and by sliding it out of the hinged brackets at the base. With the glove box out of the way, the blower motor is accessible.

Step Two- Remove the Blower Motor

With the glove box of your full-size Chevy out of the way, you can remove the blower motor. After removing the two wires that plug into the motor, you will wiggle out the black plastic shield that hides the motor. Nothing holds that shield in place, so it is just a matter of popping it off.

Next, using the one tool required for the job, you will remove each of the five 7/32-inch bolts holding the blower motor in place. From there, the motor will pull straight out of the housing.

Step Three- Installing the New Blower Motor

Installing the new blower motor is as easy as removing the old one, but before doing so, it is a good idea to take a shop vacuum and try to suck out any random debris that is in the ventilation system.

Once you have done that, you slide the new blower motor into place and tighten it down with the five 7/32-inch bolts. As Jonny reminds us, you want to install the black plastic shield before plugging in the two wires that go to the motor, but once the shield is in the place and the wires are plugged in, the project is almost done and your Chevrolet is about to have a far-stronger HVAC system.

Step Four- Glove Box and Testing

Finish up your blower motor project by reinstalling the glove box and by firing up the truck, checking to see if the new blower motor is working. If it is, you have done everything correctly and you have improved the climate control system of your GMT400 Chevrolet truck or SUV while saving yourself some money.

Patrick Rall

"Before I was old enough to walk, my dad was taking me to various types of racing events, from local drag racing to the Daytona 500," says Patrick Rall, a lifetime automotive expert, diehard Dodge fan, and respected auto journalist for over 10 years. "He owned a repair shop and had a variety of performance cars when I was young, but by the time I was 16, he was ready to build me my first drag car – a 1983 Dodge Mirada that ran low 12s. I spent 10 years traveling around the country, racing with my dad by my side. While we live in different areas of the country, my dad still drag races at 80 years old in the car that he built when I was 16 while I race other vehicles, including my 2017 Dodge Challenger SRT Hellcat and my 1972 Dodge Demon 340.

"Although I went to college for accounting, my time in my dad’s shop growing up allowed me the knowledge to spend time working as a mechanic before getting my accounting degree, at which point I worked in the office of a dealership group. While I was working in the accounting world, I continued racing and taking pictures of cars at the track. Over time, I began showing off those pictures online and that led to my writing.

"Ten years ago, I left the accounting world to become a full-time automotive writer and I am living proof that if you love what you do, you will never “work” a day in your life," adds Rall, who has clocked in time as an auto mechanic, longtime drag racer and now automotive journalist who contributes to nearly a dozen popular auto websites dedicated to fellow enthusiasts.

"I love covering the automotive industry and everything involved with the job. I was fortunate to turn my love of the automotive world into a hobby that led to an exciting career, with my past of working as a mechanic and as an accountant in the automotive world provides me with a unique perspective of the industry.

"My experience drag racing for more than 20 years coupled with a newfound interest in road racing over the past decade allows me to push performance cars to their limit, while my role as a horse stable manager gives me vast experience towing and hauling with all of the newest trucks on the market today.

"Being based on Detroit," says Rall, "I never miss the North American International Auto Show, the Woodward Dream Cruise and Roadkill Nights, along with spending plenty of time raising hell on Detroit's Woodward Avenue with the best muscle car crowd in the world.

Rall can be contacted at QuickMirada@Yahoo.com

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