GMC T-Series 1999, Owner'S Manual, Page: 232 / 344

yellow blue
6-46
To get into the box, you first have to remove the top
cover. To do that, remove the two 8 mm bolts on top and
the single 8 mm bolt at the top front. Then, pull the
cover toward you and lift it off.
You can then remove the front cover if you need to, by
removing the two 8 mm bolts and pulling it off.
When you’re through, be sure to put on the front cover,
before you put on the top cover.
Fuel Filter (Gasoline Engines)
The steel fuel filter is located inside the passenger’s side
frame rail at the rear of the cab. See your Maintenance
Schedule for recommended service intervals.
Fuel Filter (Diesel Engines)
The AC
R
fuel filter is located in the component box.
See your Maintenance Schedule for recommended
service intervals.