D 250 Pickup V8-360 5.9L VIN W (1987)
Technical Service Bulletin # 250387A
Date: 871116
High Altitude Conversion Packages
Models
1987 N, S, B, D, W, AW and AD
Subject
High Altitude Conversion Packages & Adjustments For Improved Engine Performance
Index
EMISSIONS
Date
November 16, 1987
No.
25-03-87 REVISION A (C3-25 REV A)
NOTE:
THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 25-03-87, WHICH SHOULD BE REMOVED FROM YOUR
FILES. THIS NEW BULLETIN HAS BEEN UPDATED TO INCLUDE 2.2L CALIFORNIA "S" BODY WITH AUTOMATIC
TRANSMISSION AND ALL 3.9L 4 X 4 "N" TRUCK WITH MANUAL TRANSMISSION.
Packages are now available to accommodate a customer who may wish to convert a 1987 low altitude vehicle for improved high altitude (over 4,000 feet
above sea level) engine performance.
Vehicles with the low altitude package transferred to service in high altitude areas may exhibit undesirable driveability. However, the installation of a
high altitude conversion package is voluntary and at the customer's expense
The high altitude field conversion packages and procedures outlined below have been authorized on the following 1987 nonaltitude equipped engine
families in service at altitudes above 4,000 feet above sea level.
Conversion Instructions
FIGURE 1
Sea Level to Altitude
IMPORTANT:
IN ALL OF THE CONVERSION PROCEDURES YOU WILL BE REQUIRED TO INSTALL A NEW VEHICLE EMISSION
CONTROL INFORMATION UPDATE LABEL PN 4275084.
THIS LABEL HAS TWO AREAS THAT ARE IMPACT IMPRINTABLE WITH A TYPEWRITER (SEE FIGURE 1).
If you are required to readjust timing, curb idle speed, or fast idle speed to a specification different than the original VECI label specification, type in the
new specification. If you are
