NMTRUCKER
Well-known member
I have a ‘23 GMC SIERRA 1500 with the LZ0 3 liter diesel. I have been looking for a locking fuel cap since I purchased the truck but no one sells an effective locking fuel cap for this model. Therefore, I decided to make my own locking fuel door. I’m not worried about someone stealing my diesel fuel but I’m concerned someone could dump something into my fuel that would destroy my high pressure fuel system which needless to say would be expensive.
So I purchased a replacement fuel door (Matt black) from eBay for $39.50 and a compartment key lock (JR PRODUCTS 00175) from Amazon for $13.67.
The original fuel door just slides off the swing mechanism when you pull it straight out (it’s plastic). I then installed the replacement fuel door and drill a pilot hole through the fuel door and swing mechanism. Then I removed the fuel door and used a step drill to enlarge the pilot hole to 0.75”. I did the same thing to the pilot hole in the swing mechanism. Then I reinstalled the fuel door and installed the compartment lock and lock pawl. I put a piece of green paint tape on the fuel door housing where the locking pawl would have to slide into. Next I took a magic marker and coated the side of the locking pawl and quickly rotated the locking pawl to contact the green paint tape. This established the location where I needed to grind a slot for the pawl to slide into. Using a steel ruler I marked a line for the slot. Next I used a Dremel tool with two fiber cutting discs to cut the slot for the locking pawl. Last step was to use a thin file to clean up the slot.
I could have used the original fuel door for the locking mechanism but whenever I sell this truck I can put the color matched fuel door back in place. This whole project took about 45 minutes from start to finish and gives me some peace of mind when traveling. A number of project photos are included.
So I purchased a replacement fuel door (Matt black) from eBay for $39.50 and a compartment key lock (JR PRODUCTS 00175) from Amazon for $13.67.
The original fuel door just slides off the swing mechanism when you pull it straight out (it’s plastic). I then installed the replacement fuel door and drill a pilot hole through the fuel door and swing mechanism. Then I removed the fuel door and used a step drill to enlarge the pilot hole to 0.75”. I did the same thing to the pilot hole in the swing mechanism. Then I reinstalled the fuel door and installed the compartment lock and lock pawl. I put a piece of green paint tape on the fuel door housing where the locking pawl would have to slide into. Next I took a magic marker and coated the side of the locking pawl and quickly rotated the locking pawl to contact the green paint tape. This established the location where I needed to grind a slot for the pawl to slide into. Using a steel ruler I marked a line for the slot. Next I used a Dremel tool with two fiber cutting discs to cut the slot for the locking pawl. Last step was to use a thin file to clean up the slot.
I could have used the original fuel door for the locking mechanism but whenever I sell this truck I can put the color matched fuel door back in place. This whole project took about 45 minutes from start to finish and gives me some peace of mind when traveling. A number of project photos are included.
