Solution K25229168
Thursday, December 6, 2018 8:36:20 PM CET

Mack Models
Mack Model

GR-Granite , PI-Pinnacle , AN-Anthem , CHU-Pinnacle, Axle back , CXU-Pinnacle,
Axel forward , GU-Granite , TD-Titan

Volvo Models
Volvo Model

VNR , VT , VNX , VNL , VNM , VHD , VAH

Engine family
Engine family

11L Engine , 13L Engine , 16L Engine , MP7 , MP8 , MP10

Emission Standard
Emission Standard

US07 , US10 , US14 , US15 , US16 , US17 , OBD2017 , 2018

** SOLUTION **
Title

Automated Manual Transmission Gearbox Will Not Shift To High Range After Gearbox
Repair; MID 130 PSID 24 FMI 1, P1072-92 Unintentional Disengagement Of High
Range - US07 And Newer Emissions, Model Year 2008 And Newer

Cause

REMAN gearboxes may have the incorrect high range synchronizer hub installed.
There are several tooth designs (tooth spacing/pitch) for the high range synchronizer
cone and its mating parts. There is only one tooth design used in North America ( NA
). There have been instances where REMAN short gearboxes, synchronizer kits or range
housings kits have gotten the incorrect mating parts installed. The resulting mismatch
between the two components will cause the unit to not shift into high range. The unit
will pass calibration and all shifting tests when installed in the truck because the teeth
will mesh just enough to allow the calibration and tests to pass, however in operation the
inability of the unit to fully engage will cause a complaint/symptom of grinding when
shifting to high range or wont shift to high range (Gears R2 and 7-12). In either case the
unit cannot engage the high range cone and transfer power to the driveline. The unit will
operate normally in the lower gears (R1-6).

Solution

Inspection of the tooth spacing for the components prior to installation will eliminate any
potential mismatch of components and extended diagnostic time resulting from the incorrect
components.
The correct tooth spacing is approximately 10 millimeters from the center of each tooth
on the high range synchronizer center hub.

The Part Number for the correct center hub is 21448626.

The incorrect fine tooth hubs have a Part Number of 21753650.

What you will see in Tech tool if the unit gets assembled this way.
Reviewing the Gears Test ( 4311-08-04-01 ) , calibration values ( 4320-07-03-01 ) or the
Range Solenoid Test ( 4320-08-03-02 ) screens, the high range engagement will show to be
barely within the valid calibration/engagement area. The teeth will mesh just enough to allow
a good calibration and test results however the teeth are not engaged and the torque applied to
the unit will force the range out of gear.

The average high range engaged position is 33 mm (1.31 inches) range.

Solution visibility

Dealer distribution

Support Area

Americas

Function(s)/component(s) affected
Function affected

gear shifting , engagement

Function Group
Function Group

43 gearbox

Customer effect
Main customer effect

acceleration/speed , efficiency/abnormal behavior

Noise

grinding

Road behaviour

driveability

Fault code(s)
OBD 2013 Diagnostic
Trouble Codes
NA_MIDs

P1072-92
MID 130 PSID 24 FMI 1

Conditions
Vehicle operating mode
Frequency of occurrence of
problem

when driving
random

Other conditions

after a workshop procedure on the vehicle

Administration
Author

UT9268H

Dealer ID

UT9268H

Last modified by

A241298

Creation date

17-10-2018 15:10

Date of last update

06-11-2018 22:11

Review date

17-10-2019 00:10

Status

Published

NA_Reviewer

UT9268h

NA_Author_Group

GTT