NHTSA ID Number: 10130628
Manufacturer Communication Number: 12-04-21-001B
TSB/Document Date: 2018-04-02
Summary
This technical bulletin provides a revision of 12-04-21-001A to add the 2013 model year, clarify the information from the previous bulletin and to add data throughout. The document should be reviewed and treated as new information.
Bulletin No.: 12-04-21-001B
Date: Apr-2013
Subject:
Transfer Case Identification First Design vs. Second Design
Models:
2007-2013 Cadillac
Escalade Models
2007-2013 Chevrolet Avalanche, Silverado, Suburban, Tahoe
2007-2013 GMC Sierra, Yukon, Yukon Denali
Equipped with Magna X2T Transfer Case (RPOs NQF, NQG, NQH or NP0)
This bulletin is being revised to add the 2013 model year, clarify the information from the previous bulletin and to add data
throughout. The document should be reviewed and treated as new information. Please discard Corporate Bulletin Number
12-04-21-001A (Section 04 – Driveline/Axle).
The purpose of new product information is to document important product changes that occur either model year-to-model year or interim model year.
Changes may include one or more of the following items:
•
Specification changes
•
New sealants and/or adhesives
•
Disassembly and assembly procedure revisions
•
Mechanical and diagnostic procedure revisions
•
New special tools required
•
Interim model year design changes
•
A component comparison from the previous model year
Interim Model Year Design Change – NQF/NQG/NQH/NPO Front Output Shaft, Deflector, Seal
1
Interim 2012 model year, a new design front output shaft deflector (3) was implemented into production for second design NQF–HD/SHD and NQG–HD
applications. First design 2011 model year NQF and NQG applications can be identified as not having the deflector on the front output shaft.
For service, the new design front output shaft, deflector and new design seal may be installed on current and prior model year Magna NQF–HD/SHD, NQG–
LD/HD, NQH–LD/HD and NP0 applications providing the new design front output shaft is also installed. The front output shaft deflector is to be installed using
the J 8092driver handle (1) and DT 50649seal installer (2).
2
The new design deflector (1) can be installed onto all current and prior model year Magna RPOs NQF, NQG, NQH and NPO applications providing the new
design front output shaft (2) is also installed. Second design front output shafts can be identified by the machined area on the OD output end of the shaft (2).
First design front output shafts can be identified by the dust boot clamp groove (3) located at the OD output end of the shaft. The new design slinger will NOT
install onto the first design shafts.
Service Parts Release Usage Change – NQH/NPO Control Actuator Levers
Light Duty (LD) 2007-2010 MP3023-NQH and 2010 MP3010-NP0 production transfer cases are built with LD control actuator levers (3 and 6) and are used
with 13 mm (0.52 in) diameter control actuator lever balls (5).
Heavy duty (HD) 2007-2010 MP3024-NQH production transfer cases are built with HD control actuator levers (3 and 6) and are used with Heavy
10 mm (0.39 in) control actuator lever balls.
When replacement of one or both of the LD control actuator levers is required, it is necessary to replace both of the levers and all three balls with the HD
components as a set. It is also necessary to re-measure and adjust clutch pack clearances as required and to perform the Transfer Case High/Low Clutch
Reset. Refer to Measuring/Adjusting Clutch Assembly Height in Transfer Case Assemble, Transfer Case Description and Operation and Transfer Case
High/Low Clutch Reset. Heavy duty (HD) components are the only parts available for service.
Interim Model Year Design Change – NQG High/Low Shift Fork, Fork Pad, and High/Low Clutch
Interim 2012 model year the High/Low shift fork, fork pad and High/Low clutch design changed. The first design forks (2) can be identified as having three flat
un-notched fork pad areas with three separate fork pads (1). The second design forks (4) can be identified as having a half-round shaped pad area with three
notches for pad orientation and installation and upper and lower half-round fork pads (3). The second design shift fork (4) and pads (3) are the only design
available for service and must be used with the second design High/Low clutch.
3
Interim 2012 model year the High/Low shift fork, fork pad and High/Low clutch design changed. The first design high/low clutch (1) can be identified by having a
73 mm (2.87 in) OD rear flange (2). The second design high/low clutch (3) can be identified by having a 76 mm (2.99 in) OD rear flange (4).
For service:
•
The first design 73 mm (2.87 in) high/low clutch may NOT be used with the second design fork and pad.
•
The second design 76 mm (2.99 in) high/low clutch must be used with the second design fork and fork pad.
•
The second design 76 mm (2.99 in) high/low clutch may also be used with the first design fork and pad if first design fork replacement is not required.
Interim Model Year Design Change – NQF/NQG/NQH Front Case Half Assembly, Input Shaft, Planetary Carrier
High/Low Clutch
Interim 2012 model year for Magna light-duty and heavy-duty transfer case RPOs NQF / NQG / NQH, a second-design front case half assembly, planetary
internal gear, gear retaining ring, locking plate, thrust washer-front, input shaft, pilot bearing, thrust washer-rear, high/low planetary carrier and high/low clutch
were implemented into second-design assemblies.
The second-design light duty (LD), heavy duty (HD), and super-heavy duty (SHD) applications have a reduced OD dimension carrier and the second-design
planetary internal gear has a reduced ID dimension. The planetary internal gear is a press-fit non-serviceable component and must be serviced with the front
case half assembly. In service it is possible that a new or remanufactured transfer case may contain first or second-design content.
If a second-design transfer case has been installed into a vehicle that originally contained a first-design assembly, TCCM reprogramming is not required.
For production, the following transfer cases variations were produced:
•
2007-12i Magna LD NQG/NQH – produced with first-design content. First design service components are available. A second-design assembly may be
used for back-service in a first-design application.
•
2007-10 Magna HD NQF – produced with only first-design content. Service components are available.
•
2007-10 Magna HD NQG – produced with only first-design content. Service assemblies may contain either first or second design content. Both first and
second design service components are available.
•
2007-12i Magna HD NQH – produced with first-design content. First design service components are available. A second-design assembly may be used
for back-service in a first-design application.
•
2011-12i Magna SHD NQF/NQG – produced with first design content. First design service components are available. A second-design assembly may be
used for back-service in a first-design application.
•
2012i-13 Magna LD NQG/NQH – produced with second-design content. Second design service components are available.
•
2012i-13 Magna HD NQH – produced with second-design content. Second design service components are available.
•
2012i-13 Magna SHD NQF/NQG – produced with second-design content. Second design service components are available.
Production Assembly Breakpoints
The design level and component content of the transfer case can be determined by referencing the assembly part number located on the identification label.
4
figure-sio
Production Assembly Breakpoints
First Design Assembly
PN
Second Design
Assembly PN
RPO
Approximate
Production Breakpoint
Vehicle/Transmission
RPO
24256476
24261560
NP0
March 2012
K100 / MYC
24256475
24261517
NQH
January 2012
K200 / MYD
24256474
24261516
NQH
January 2012
K100 / M99
24256473
24261515
NQH
January 2011
K100 / M30
24256472
24261514
NQH
December 2011
K100 / MYC
24257578
24261513
NQF
December 2011
K200 / MYD
24257577
24261512
NQF
January 2012
K200 / 300 / MW7
24257576
24261511
NQF
December 2011
K200 / 300 / MYD
24257581
24261510
NQG
January 2011
K200 / MYD / +Z49
24257580
24261509
NQG
January 2012
K200 / 300 / MW7
24257579
24261508
NQG
December 2011
K200 / 300 / MYD / -Z49
24252685
24261507
NQG
December 2011
K100 / M30
24252684
24261506
NQG
January 2011
K100 / MYC
Service Parts List
5
Magna Light Duty NQG/NQH/NP0 – First Design
Callout
Description
GM PN
Service Usage
1
Front Case Half Assembly -
19132998
NQH
19133000
NQG
19255999
NP0
w/gear (2) and ring 3)
1
Front Case Half Assembly w/gear (2) and ring (3)
1
Front Case Half Assembly - w/o
gear (2) and ring (3)
2
High/Low Internal Gear-Not
serviceable-part of case
assembly
NO/PN
NQG/NQH
3
High/Low Internal Gear
Retaining Ring
19133009
NQG/NQH
4
High/Low Planetary Carrier
Retaining Ring
19132997
NQG/NQH
5
High/Low Locking Plate-Single
tab design
19132996
NQG/NQH
6
Thrust Washer-Front-No tab
design
19132995
NQG/NQH
6
7
Input Shaft Assembly - w/pilot
bearing
19132977
NQG/NQH-w/M30
7
Input Shaft Assembly-w/pilot
bearing
19132978
NQH-w/M99
NQG/ NQH-w/MYC
7
Input Shaft Assembly-w/pilot
bearing
19255997
NP0-w/MYC
8
Pilot Bearing
19132983
NQG/NQH/NP0
9
Thrust Washer-Rear-No tab
design
19132995
NQG/NQH
10
High/Low Planetary Carrier
Assembly- Three pinion design
19132986
NQG/NQH
11
High/Low Clutch
19260068
NQG/NQH - w/M30
11
High/Low Clutch
19260067
NQG/NQH w/MYC and NQH
w/M99
Magna Light Duty NQG/NQH/NP0 – Second Design
Callout
Description
GM PN
7
Service Usage
1
Front Case Half Assembly -
19299077
NQH
19299078
NQG
19299076
NP0
w/gear (2) and ring (3)
1
Front Case Half Assembly w/gear (2) and ring (3)
1
Front Case Half Assembly – w/o
gear (2) and ring (3)
Note: The second design NP0
front case half assembly is
interchangeable with first design
2
High/Low Internal Gear-Not
serviceable-part of case
assembly
NO/PN
NQG/NQH
3
High/Low Internal Gear
Retaining Ring
14037953
NQG/NQH
4
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TSB/Document ID: 12-04-21-001B
Replacement Service Bulletin Number:
MFR Communication Date: 2013-04-11
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
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