A/T - THM 440-T4 Harsh Upshifts

Bulletin No. T 87-52
File in Group 7
Number 151
Corp. Ref. No. 677122
Date Dec. '86

Aneroid Vacuum Modulator:

SUBJECT: THM 440-T4 HARSH UPSHIFTS -- HIGH ALTITUDE

MODELS AFFECTED: 1985-1986 DE VILLE AND FLEETWOOD 1986 ELDORADO AND SEVILLE


Some 440-T4 transaxles operated in designated high altitude areas may exhibit harsh upshifts. It is also possible to experience the condition in any mountainous elevation above 4,000 feet. The condition is the result of low engine vacuum to the vacuum modulator causing high line pressure. To correct the condition, an aneroid vacuum modulator kit has been released. The following service packages have been released for specific model identification codes.

Transaxle
Service Package Model Identification

8646966 5AM, 5AR, 5AF, 6AMH,

6AAH, 6ABH, 6ACH, 6AFH

8646967 6ADH, 6ARH


Each Package Contains

Vacuum Modulator (Aneroid) Revised Modulator Valve "O" Ring Seal Valve Body Spacer Plate Gaskets (5) Instruction Sheets (2) Cup Plug (Orificed - See Attachment)

IMPORTANT: At the same time a new vacuum pipe from the throttle body to the vacuum modulator must be installed. The new steel line is formed to accommodate relocation of the vacuum connector on the modulator from the end to the side.

NOTE: Do not attempt to reform the original steel line or connect the line and modulator with additional hose.

Part Number Description Application

1637147 Pipe 1985-86 "C" Car
1641441 Pipe 1986 "E/K" Car

Refer to the appropriate Service Information Manual, 440-T4 Transaxle Unit Repair section for service procedures.

* Attached is a map and list of designated high altitude areas, by county, in the United
States.

Use Labor Operation K6570 at 2.7 hours for De Villes and 3.2 hours for Eldorados and Sevilles.

EPA Designated High Altitude Counties:

DESIGNATED HIGH ALTITUDE COUNTIES* Requiring High Altitude Emission Control
STATE OF ARIZONA Apache Navajo

STATE OF COLORADO
Adams Jefferson
Alamosa Lake
Arapahoe La Plata
Archuleta Larimer
Boulder Las Animas
Chaffee Lincoln
Clear Creek Mesa
Conejos Mineral
Costilla Moffat
Crowley Montezuma
Custer Montrose
Dolores Morgan
Delta Ouray
Denver Park
Douglas Pitkin
Eagle Pueblo
Elbert Rio Blanco
El Paso Rio Grande
Fremont Routt
Garfield Saguache
Gilpin San Juan
Grand San Miguel
Gunnison Summit
Hinsdale Teller
Huerfano Washington
Jackson Weld


STATE OF IDAHO

Bannock Custer
Bear Lake Franklin
Bingham Fremont
Blaine Jefferson
Bonneville Madison
Butte Minidoka
Camas Oneida
Caribou Power
Cassia Teton
Clark Valley

STATE OF MONTANA
Beaverhead Madison
Deer Lodge Meagher
Gallatin Park
Jefferson Silver Bow

STATE OF NEBRASKA
Banner Sioux
Kimball
STATE OF NEVADA
Carson City Humboldt
Douglas Lander
Elko Lyon
Esmeralda Mineral
Eureka Storey
White Pine

STATE OF NEW MEXICO
Bernalillo Mora
Catron Rio Arriba
Colfax Sandoval
Curry San Juan
De Baca San Miguel
Grant Santa Fe
Guadalupe Sierra
Harding Socorro
Lincoln Taos
Las Alamos Torrance
Luna Union
McKinley Valencia


STATE OF OREGON

Lake

STATE OF UTAH
Beaver Piute
Box Elder Rich
Cache Salt Lake
Carbon San Juan
Daggett Sanpete
Davis Sevier
Duchesne Summit
Emery Tooele
Grand Uintah
Iron Utah
Juab Wasatch
Kane Wayne
Millard Weber
Morgan

STATE OF WYOMING
Albany Natrona
Carbon Niobrara
Converse Park
Fremont Platte
Goshen Sublette
Hot Springs Sweetwater
Johnson Teton
Laramie Uinta
Lincoln Weston
*Counties which have substantially all of their area above 4000 ft. Ref. Federal Register, Vol. 42, No. 76, April 20, 1977, pg. 20464