GMC 1996 Sonoma Owner's Manual page 310

I
Short TripKity Maintenance Schedule
I
50.000 A
Yes
(83
000 km)
0
Change automatic transmission fluid and
filter if the vehicle is mainly driven under
one or more of these conditions:
-
In heavy city traffic where the outside
temperature regularly reaches
90
O
F
(32°C) or higher.
-
In hilly or mountainous terrain.
-
When doing frequent trailer towing.
-
Uses such as found in taxi, police or
delivery service.
Lfyou
do
not
use y o ~ l r vehicle under any
o f
these conditions, the fluid and filter do not
require changing.
Manual transmission fluid doesn't require change.
I
I I
DATE ACTUAL MILEAGE SERVICED B Y
7-18