Jeep J-10 Series 1982 Technical & Service Manual page 777

In operation, the Trac-Lok clutches are engaged by
two concurrent forces. The first being preload force
exerted through Belleville springs contained within the
clutch packs and the second is from separating forces
generated by the side gears as torque is applied through
the ring gear.
The Trac-Lok design provides the normal differential
action needed for turning corners and for the trans
mittal of equal torque to both wheels when driving
straight ahead. However, when one wheel loses traction
and spins, the clutch packs transfer additional torque to
the wheel having the most traction. Trac-Lok differen
tials resist wheel spin on bumpy roads and provide more
pulling power when one wheel loses traction. Pulling
power is provided continuously until both wheels lose
traction. If both wheels slip due to unequal traction,
Trac-Lok operation is normal. In extreme cases of differ
ences in traction, the wheel with the least traction may
spin after the Trac-Lok has transferred as much torque
as possible to the nonslipping wheel.
LUBRICATION
Use Jeep axle lubricant, or equivalent marked SAE
85W-90, grade GL-5 in Trac-Lok axles. In addition, the
only acceptable method for cleaning the Trac-Lok differ
ential is by disassembling the unit and wiping it clean
using shop towels.
NOTE: The Trac-Lok differential is serviced at the
same time intervals as the standard differential.
Trac-Lok Lubricant Change
(1) Warm axle lubricant. Operate vehicle in gear, on
hoist, with wheels off floor for minimum of 5 minutes at
30 mph.
WARNING: Never attempt to operate a Trac-Lok
equipped vehicle in gear with only one wheel raised. The
vehicle could propel itselfoff the jack and cause damage
or personal injury.
(2) Stop engine and raise vehicle on hoist.
(3) Remove axle housing cover drain plug or cover
and drain lubricant while it is warm. If cover is re
moved, discard cover gasket.
(4) Remove any residual lubricant from axle hous
ing using shop cloths.
(5) Install drain plug. If axle housing cover was
removed, clean cover and housing mating surfaces and
apply Jeep Gasket-In-A-Tube, or equivalent sealer to
cover and housing mating surfaces. Install cover and
cover bolts. Tighten cover bolts to 20 foot-pounds (27
N»m) torque.
(6) Refill axle housing with specified lubricant only.
Refer to Specifications for lubricant capacities of vari
ous axle models.
AXLES - FRONT HUBS 2F-41
(7) Operate vehicle on road for approximately ten
miles (16 km). Make at least ten figure eight turns to
flush old lubricant out of clutch packs.
(8) Return vehicle to shop and raise vehicle on hoist.
(9) Drain and replace axle lubricant again. If axle
housing cover is removed, be sure to clean cover and
housing mating surfaces and reapply Jeep Gasket-In-A-
Tube, or equivalent sealer to mating surfaces before
reinstalling cover.
(10) Lower vehicle.
(11) Road test vehicle and verify proper Trac-Lok
operation.
NOTE: If a slight chatter occurs after flushing and
refilling the Trac-Lok differential, drive the vehicle an
additional ten to twenty miles (16 to 32 km) or until
chatter stops. If the chatter persists after twenty (32
km) or more miles of driving, an overhaul may be
necessary.
DIAGNOSIS
If noisy or rough operation such as chatter occurs
when turning corners, the most probable cause is in
correct or contaminated lubricant. Before removing the
Trac-Lok unit for repair, drain, flush, and refill the axle
with the specified lubricant. Refer to the lubricant
change procedure under Lubrication. A complete lubri
cant drain and refill with the specified lubricant will
usually correct chatter.
Trac-Lok Operational Test
Trac-Lok operation can be checked quickly using the
following test.
(1) Position one wheel on solid, dry pavement and
opposite wheel on ice, mud, grease, orsimiliar low trac
tion surface.
(2) Increase engine rpm gradually to obtain max
imum traction prior to breakaway. Ability to move ve
hicle effectively will demonstrate proper performance.
NOTE: If the test is performed on extremely slick sur
faces suchas ice or grease coated surfaces, some ques
tion may exist as to proper performance. In these
extreme cases, a properlyperforming Trac-Lok willpro
vide greater pulling power by lightly applying the park
ing brake.
OVERHAUL
Disassembly
(1) Remove differential from axlehousing. Removal
procedures are same as outlined for standard differen
tial. Refer to figures 2F-60 and 2F-61 for parts
nomenclature.