A low transmission lubricant level is generally the result of a leak, inadequate lubricant fill or an incorrect lubricant
level check. A correct lubricant level check can only be made when the vehicle is level. Also allow the lubricant to
settle for a minute or so before checking. Always check the lubricant level after any addition of fluid to avoid an
incorrect lubricant level condition.

Leaks can occur at mating surfaces of the gear case, adaptor or extension housing, or from the front/rear seals. A
leak could also be the result of an overfill condition. Leaks at the rear of the extension or adapter housing will be
from the housing oil seals. Leaks at component mating surfaces will probably be the result of inadequate sealer,
gaps in the sealer, incorrect bolt tightening or use of a non-recommended sealer. A leak at the front of the trans-
mission will be from either the front bearing retainer or retainer seal. Lubricant may be seen dripping from the clutch
housing after extended operation. If the leak is severe, it may also contaminate the clutch disc causing the disc to
slip, grab and or chatter.

HARD SHIFTING

Hard shifting is usually caused by a low lubricant level, improper or contaminated lubricants. The consequence of
using non-recommended lubricants is noise, excessive wear, internal bind and hard shifting. Substantial lubricant
leaks can result in gear, shift rail, synchro, and bearing damage. If a leak goes undetected for an extended period,
the first indications of component damage are usually hard shifting and noise.

Component damage, incorrect clutch adjustment or damaged clutch pressure plate or disc are additional probable
causes of increased shift effort. Incorrect adjustment or a worn/damaged pressure plate or disc can cause incorrect
release. If clutch problem is advanced, gear clash during shifts can result. Worn or damaged synchronizer rings can
cause gear clash when shifting into any forward gear. In some new or rebuilt transmissions, new synchro rings may
tend to stick slightly causing hard or noisy shifts. In most cases this condition will decline as the rings wear-in.

TRANSMISSION NOISE

Most manual transmissions make some noise during normal operation. Rotating gears generate a mild whine that is
audible, but generally only at extreme speeds. Severe highly audible transmission noise is generally the initial indi-
cator of a lubricant problem.

Insufficient, improper or contaminated lubricant will promote rapid wear of gears, synchronizers, shift rails, forks and
bearings. The overheating caused by a lubricant problem, can also lead to gear breakage.

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MANUAL TRANSMISSION - NV5600 - SERVICE INFORMATION

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REMOVAL

1. With vehicle in neutral, position it on a hoist.

2. Remove shift boot floorpan screws and slide boot

upward on the shift lever.

3. Remove shift tower/isolator plate bolts and remove

shift tower/isolator plate from transmission case.

4. Remove skid plate, if equipped.

5. Mark propeller shaft/shafts and axle yokes for

installation reference and remove shaft/shafts.

6. Remove exhaust system as necessary.

7. Disconnect wires at backup light switch.

8. Support engine with safety stand and wood block.

9. If transmission is to be disassembled, remove drain

bolt (2) at bottom of PTO cover (1) and drain lubri-
cant from transmission.

10. Remove clutch slave cylinder splash shield, if equipped.

11. Remove clutch slave cylinder bolts and move cylinder aside for clearance.

12. Remove wire harness from clips on transmission.

TWO WHEEL DRIVE

1. Remove bolts/nuts mounting transmission to the rear mount.

2. Support and secure transmission with safety chains to a transmission jack.

3. Remove rear crossmember bolts and pry out crossmember.

4. Remove transmission clutch housing bolts at the engine block.

5. Slide transmission and jack rearward until input shaft clears clutch disc and pressure plate.

6. Lower transmission jack and remove transmission from under vehicle.

FOUR WHEEL DRIVE

1. Disconnect transfer case shift linkage at transfer case range lever.

2. Support and secure transfer case with safety chains to a transmission jack.

3. Remove transfer case mounting nuts.

4. Move transfer case rearward until input gear clears transmission mainshaft.

5. Lower transfer case assembly and move it from under vehicle.

6. Support and secure transmission with safety chains to a transmission jack.

7. Remove bolts/nuts attaching transmission mount to rear crossmember.

8. Remove rear crossmember bolts and pry out crossmember.

9. Remove transmission clutch housing bolts at the engine block.

10. Move transmission rearward until input shaft clears clutch disc.

11. Lower transmission and remove it from under vehicle.

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MANUAL TRANSMISSION - NV5600 - SERVICE INFORMATION

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DISASSEMBLY

NOTE: Use Fixture 8241 for moving and handling
the transmission. The fixture supports the trans-
mission at the center of gravity in order to ease
mounting the transmission into the build fixture.

1. Mount transmission (2) into Fixture 8230 (1).

2. Rotate transmission to a horizontal position.

3. Remove shift tower (1) from transmission (2).

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MANUAL TRANSMISSION - NV5600 - SERVICE INFORMATION

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