Specifications

Prepare Parts for Reassembly
38 MAINTENANCE MANUAL
• If the positions of the tire marks are more
than3.6 degrees from each other: Check to the
vehicle manufacturer for further information.
8. Remove the safety stands and lower the ve-
hicle.
Hypoid Gear Set Teeth Numbers Stam-
ped on the Forward and Rear Axle Drive
Pinions
When the inter-axle driveline or differential
are removed for maintenence, you can check
the hypoid gear set teeth numbers stamped on
the forward and rear axle drive pinions.
WARNING
1. Park the vehicle on a level surface.
2. Block the wheels to prevent the vehicle from
moving.
To Identify the Gear Teeth Number on
the Forward Axle Drive Pinion
1. Remove the forward pinion cover. See the
vehicle manufacturer’s procedures.
2. Look into the differential housing. Identify and
record the gear set teeth numbers stamped
on the drive pinion end. Figure 4.19.
Figure 4.18
Figure 4.19
Figure 4.20
3. Calculate the hypoid gear set ratio by divid-
ing the larger number by the smaller num-
ber. Figure 4.19.
To Identify the Gear Teeth Number on
the Rear Axle Drive Pinion
1. Remove the inter-axle driveshaft. Seethe
vehicle manufacturer’s procedures.
2. Identify and record the gear set teeth num-
bers stamped on the end of the rear axle
drive pinion. Figure 4.20.
3. Calculate the hypoid gear set ratio by divid-
ing the larger number by the smaller num-
ber. Figure 4.20.
Compare Both Hypoid Gear Set Ratios
1. Both ratios 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.
LARGER NUMBER
LARGER NUMBER
=
=
SMALLER NUMBER
SMALLER NUMBER
If the mark appears in
the shaded area, the tandem
gear set is incorrectly matched.
If the mark appears in this area, the tandem axle gear
set is correctly matched.
HYPOID GEAR
SET RATIO
GEAR SET
RATIO