DANA 53R-300, Service Manual

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the tangs on the pressure ring are approximately 1/8” (.125 in)/[3mm] from
being flush with the face of the brake housing.
23. Install first steel reaction plate in pressure ring.
24. Install first friction disc in pressure plate.
25. Install second reaction disc.
26. Install second friction disc, aligning the four (4) oil grooves in the second
friction disc with the oil grooves in the first friction disc.
27. Alternate steel reaction plates and friction discs until five (5) plates and five
(5) discs are installed. The installation sequence begins with a reaction plate
and ends with a friction disc.
Note:
Always align friction disc oil grooves with previously installed friction disc oil
grooves. Careful alignment of friction disc teeth at this time will facilitate
installation of the wheel hub.
28. Install new square cut sealing ring in brake housing o-ring groove.
Piston and Brake Cover Assembly:
A. Install new piston outer o-ring and seal ring in brake cover outer ring
groove.
B. Install new piston inner o-ring and seal ring in inner ring groove. Use
caution not to overstretch inner o-ring and seal ring.
C. Make sure inner and outer seal rings are in fully seated position in ring
grooves. Lightly lubricate both inner and outer seals.
D. To facilitate installing the piston in the brake cover, a simple installation
tool can be made. A drawing of the tool is on page ( ). Three (3) of these
tools are needed.
E. The three (3) steel blocks with a hole in them are used with three (3)
brake cover bolts, washers and three (3) 5/8-11 NC nuts. The bolts come
through the cover approximately 120° apart. The piston is positioned in
the piston groove with the chamfer edges down and the three threaded
holes up. Position an installing steel block on each of the cover bolts.
Install a washer and a nut on each bolt. Locate long portion of block over
piston. Tighten nuts evenly on all three blocks to compress piston into
piston groove. Use caution as not to damage piston inner and outer
sealing rings. Push piston in groove until it is flush with face of cover.
Remove nuts, washers, installation blocks and cover bolts.
F. Position two new square cut sealing rings in cover ring grooves. A light
coat of oil will hold rings in position during cover installation. Mark the
fluid hole locations on the edge of the cover for alignment with the holes
in the brake housing.
Brake Cover Installation on Housing
29. Mark edge of brake housing at the two fluid hole locations.
30. Position brake cover on brake housing, aligning fluid hole marks on cover
with marks on brake housing. Install cover on housing using caution not to
disrupt sealing rings at fluid openings.
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