SB-10044821-9833

M a c k Tr u c k s , I n c .
Greensboro, NC USA

S ervic e P rogram
Tr u c k s
Date

Group

No.

Release

Page

6.2012

818

001

01

1(4)

Cab Leveling Valve Bracket
GU

P I 0 7 8 9 , C a b L e v e l i n g Va l v e B r a c k e t
(J une 201 2)

Info rmat i on
Certain MACK GU vehicles with Hours of Operations (HOS) sleepers built from 04/2011 to
01/2012 were built with the incorrect cab suspension leveling valve bracket installed. Also the
air spring support bracket may be mounted incorrectly on the frame. These issues can cause
the cab shock to be extended fully when the air spring is inflated. If this occurs the proper cab
ride height cannot be obtained. To correct these issues complete the following procedure.

N o t e : Information is subject to change without notice.
Illustrations are used for reference only, and may differ slightly from the actual engine
version. However, key components addressed in this information are represented as
accurately as possible.

R eq ui red P a rt s
1 – 21940307 Cab Leveling Valve Bracket

P V 7 2 9-PI0789
9

USA53705

M a c k Tr u c k s , I n c .
S e rv ic e P ro gra m

Date
6.2012

Group

No.

Release

818

001

01

P roc edu re
You must read and understand the precautions and guidelines in Service Information
Function Group 80, “General Safety Practices, Cab” before performing this procedure. If
you are not properly trained and certified in this procedure, ask your supervisor for training
before you perform it.
1 Secure the vehicle for service by parking it on a flat level surface, applying the parking
brake, chocking the rear wheel, and placing the transmission in neutral.
2 Disconnect all cables from the negative (ground) and positive battery terminals to prevent
personal injury from electrical shock and prevent damage to electrical components.
3

DANGER
Do not service any part of the fuel system while smoking or in the presence of flames,
sparks, or hot surfaces. Failure to follow these precautions can result in fire, which can
cause serious injury or death.

WA R N I N G
Clean up fuel spills immediately. Fuel leaked or spilled onto hot surfaces or electrical
components can cause a fire.
Position a suitable container of adequate capacity and drain the fuel tank.
4

DANGER
Never work under or around a vehicle unless it is supported on jack stands of adequate
rating. Failure to use adequate jack stands can result in the vehicle falling, which can
cause serious injury or death to anyone under the vehicle.
Position a suitable lifting device to support the fuel tank during removal.
5 Disconnect the fuel level sensor.
6 Disconnect the fuel lines.
7 Remove the fuel tank straps.
8 Remove the fuel tank from the vehicle. Secure the fuel tank in a safe location.
9 Install a suitable lifting device to support the cab.
10 Drain the air system.
11 Disconnect the cab leveling rod from the valve arm.

Page
2(4)

M a c k Tr u c k s , I n c .
S e rv ic e P ro gra m

Date
6.2012

Group

No.

Release

818

001

01

W8074224
W8074224

12 Remove the fasteners securing the cab leveling valve. Allow the valve to hang freely.
13 Remove the driver side air spring support bracket.
14 Remove the cab leveling valve bracket.
15 Slot the upper portion of the air spring support bracket as needed to provide clearance for
the top fastener (huck bolt).
16 Install the replacement cab leveling valve bracket. Only install the top most fasteners.
Ensure that there is proper alignment of the lower fasteners holes.
17 Install the driver side air spring support bracket. Only install the three fasteners in the lower
three holes in the bracket to the frame.
N o t e : Ensure that the air spring alignment dowels are positioned correctly on the bracket.
18 Install the cab leveling valve.
19 Connect the cab leveling rod.
20 Remove the fasteners securing the passenger side air spring support bracket.

Page
3(4)

M a c k Tr u c k s , I n c .
S e rv ic e P ro gra m

Date
6.2012

Group

No.

Release

818

001

01

21 Slot the upper portion of the air spring support bracket as needed to provide clearance for
the top fastener (huck bolt).
22 Install the topmost fastener in the frame and secure to prevent an open hole in the frame
rail. Relocate the passenger side air spring support bracket to the lower three holes of the
frame grid. Install all the remaining fasteners.
N o t e : Ensure that the bracket is relocated so that the fastener holes are aligned with the
lower three holes on the frame.
N o t e : Ensure that the air spring alignment dowels are positioned correctly on the bracket.
23 Reinstall fuel tank(s). Connect the fuel level sensor to the fuel tank.
24 Install the steps and anchoring straps. Tighten fasteners to 108 ±7 Nm (80 ±5 ft-lb).
25 Remove the fuel tank support device.
26 Connect the fuel lines to the fuel tank.
27 Refill fuel tank.
28 Reconnect all previously removed cables to the negative (ground) and positive battery
terminals.
29 Start the vehicle. Let the air system refill. Check the cab for proper orientation, operation
and ride height.
30 Remove cab support device.
31 Adjust cab ride height to specification, 199 mm (7.8 in) from the air bag support bracket to
the top of the air bag.
R ei mbu rs ement
Thi s repai r is c ov ered by an aut hori z ed S erv i c e P rogram. R ei mburs ement i s
obt ain ed v i a the n ormal c l ai m hand li ng proc es s .
C l a i m Ty p e ( u s e d o n l y w h e n u p l o a d i n g f r o m t h e D e a l e r B u s . S y s . )

B

Rec all Sta tus
Vehicle repaired per instruction

1- Modified per
instruction

Labor Code
Primary Labor CodeTo complete both carriers

6684C-ZZ-96
1.8 hrs.

Time to take charge and determine campaign status

101AA–0A–00
0.3 hrs.

Caus al P art

21585115

A ut hori z at io n N umbe r

PI0789

Ex piration Date

01-Jul-13

N o t e : Take Charge Time is not included in the Labor Code for this operation. Take charge
may be eligible but can only be used once per repair visit. If vehicle is having other warranty
repairs performed, take charge should be charged to the warranty repair, otherwise take
charge can be charged to this service program.

Page
4(4)