Specifications

37
Prepare Parts for Reassembly
MAINTENANCE MANUAL
Hypoid Gear Set Ratios Listed on the
IdenticationTags
1.Locatethe identicationtags rivetedtothe
forward and rear of differential. Figure 4.15.
1. Park the vehicle on a level surface.
2. Engage the power divider and shift the
transmission into NEUTRAL.
3. Block the wheels to prevent the vehicle from
moving.
4.Use ajack to raisethe vehicle untilall the
tandem drive axle wheels clear the ground.
Support the vehicle with safety stands.
5. Mark the forward and rear tires at identical
relative positions.Figure 4.16
• Iftheaxleratiosshownontheidentication
tags are not within one percent of each oth-
er: See the vehicle manufacturer for further
information
Rotate the Forward Driveshaft to Check
the Hypoid Gear Set Ratio
WARNING
Park the vehicle on a level surface. Block the
wheels to prevent the vehicle from moving. Sup-
port the vehicle with safety stands. Do not work
underavehiclesupportedonlybyjacks.Jacks
can slip and fall over. Serious personal injury
and damage to components can result.
2. Compare the axle ratios shown on both
tags. To operate correctly, the axle ratios
for both axles must be within one percent of
each other. To calculate the percentage dif-
ference between the axle ratios, refer to the
equation in Table E.
Table E:
6. Turn the forward driveshaft in one direction
by hand until the forward tire completes two
rotations. Figure 4.17. The forward tire must
rotate two times only. If the forward tire ro-
tates more than or less than two rotations,
the angle measurements you make in Step 7
will be inaccurate
7. Note the positions of the tire marks you previ-
ously made. On a correctly matched tandem
axle gear set, both tire marks will be within ±
3.6 degrees of each other. Figure 4.18.
FigurE 4.15
Figure 4.16
Figure 4.17
PREVIOUS
MARKS
MARKS
Rotate two full
turns of forward
tire.
Larger Ratio – Smaller
Ratio
X 100 -
Percentage Dif-
ference Between
Axle Ratios
Smaller Ratio