Differential b.
THE PINION CONE CENTRE DISTANCE
1.
The correct cone centre distance is etched on the machined face of the pinion. Also etched on this face is the set number of the pinion and bevel gear. Ensure that the pinion and bevel gear are matched.
NOTE: Spline shaft mounting distance is directly etched on the bevel gear machined face as 0.636" or any. 2.
Install the spline shaft using a shim pack of 0.090" between the bearing cone and the Transmission case.
3.
Using parallel gauge block (Special Tool) measure the distance between carrier LH mounting axis on transmission case to bevel pinion machined surface.
EXAMPLE: If spline shaft mounting distance is directly etched as 0.636" and thickness of parallel gauge block is 0.628" then feeler gauge of 0.008" should go. If it is going very easily then measure the looseness, if the feeler gauge of 0.012" is going instead of 0.008", it means distance between spline shaft and transmission case is more by 0.004". Therefore 0.004" of shims must be added. Similarly if the feeler gauge of 0.004" is going instead of 0.008" then remove the shims 0.004" to increase the distance. NOTE:
Measurements should be made every 90º and the average of these readings should be taken.
4.
With the correct shim pack assemble the bevel pinion with the gears and shaft. Shims to be assembled between head bearing of spline shaft and bearing mounting counter bore on transmission case.
5.
Recheck the mounting distance.
c.
BACKLASH ADJUSTMENT The backlash for a given pair of spline shaft (pinion gear) and bevel (ring or crown) gear is determined at the factory and is etched on the outer surface of the bevel gear. Adjust backlash to the etched number ± 0.05 mm (0.002"), preferable toward the lower limit.
NOTE: The backlash is adjusted by removing shims from one carrier on transmission case and fitting them to other side. The same quantity of shims must be maintained at all time as otherwise the “PRE-LOAD” of the tapered roller bearing will be upset. 1.
Rigidly mount a dial indicator against a gear tooth, being sure that indicator system is perpendicular to the tooth surface at the extreme heels.
2.
Engage two sliding gears in mesh this will held the position quite but a pinch bar used as a lever against one of the teeth of the gear will ensure complete rigidity.
3.
Rock the bevel gear noting total indicator reading.
4.
Repeat measurement every 90º of the bevel gear.
5.
Excessive backlash is reduced by removing shims from the right hand bull pinion bearing cage and assembling them to the left hand bull pinion bearing cage and vice-versa. A 0.005" shim transfer approximates to a reduction or increase of 0.003" backlash.
During the cone center adjustment it is imperative that backlash be present.
Preload
Ring Gear Differential Case
4.4 - 6.6 lbs.
Spline Shaft
5.7 - 8.15 lbs.
35 Series 4WD, Model - 3535, 4035, 4535 and 5035 SM June’08
E-43
