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. These recommendations will ensure an accurate check and avoid an
underfill or overfill condition. Always check the lubricant level after any addition of fluid to avoid an incorrect lubricant
level condition.

Leaks can occur at the mating surfaces of the gear case, adaptor or extension housing, or from the front/rear seals.
A suspected 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 inad-
equate sealer, gaps in the sealer, incorrect bolt tightening or use of a non-recommended sealer. A leak at the front
of the transmission 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 caus-
ing 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 synchro 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, synchros, shift rails, forks and
bearings. The overheating caused by a lubricant problem, can also lead to gear breakage.

REMOVAL

1. Shift transmission into Neutral.

2. Remove shift boot screws from floorpan and slide

boot upward on the shift lever.

3. Remove shift lever extension from shift tower and

lever assembly.

4. Remove shift tower (1) bolts (3).

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5. Remove shift tower and isolator plate from trans-

mission shift cover.

6. Raise and support vehicle.

7. Remove skid plate, if equipped.

8. Mark propeller shaft and axle yokes for installation

reference and remove shaft/shafts.

9. Remove exhaust system Y-pipe.

10. Disconnect speed sensor and backup light switch

connectors.

11. Support engine with safety stand and a wood

block.

12. If transmission is to be disassembled, remove drain bolt (2) at bottom of PTO cover (1) and drain lubricant.

TWO WHEEL DRIVE

1. Remove bolts attaching transmission to rear crossmember mount.

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

3. Remove rear crossmember bolts and pry out crossmenber.

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

NOTE: The hydraulic linkage has a quick connect at the slave cylinder. This fitting should not be discon-
nected.

5. Remove transmission harness wires from clips on transmission shift cover.

6. Remove transmission to clutch housing bolts.

7. Slide transmission and jack rearward until input shaft clears clutch housing.

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

FOUR WHEEL DRIVE

1. Disconnect transfer case shift linkage (2) at trans-

fer case range lever. Then remove transfer case
shift mechanism from transmission (1).

2. Support and secure transfer case to transmission

jack with safety chains.

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 transmission harness from retaining clips

on transmission shift cover.

8. Remove bolts/nuts attaching transmission mount to

rear crossmember.

9. Remove rear crossmember bolts and pry out crossmenber.

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

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

NOTE: The hydraulic linkage has a quick connect at the slave cylinder. This fitting should not be discon-
nected.

12. Remove transmission to clutch housing bolts.

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MANUAL TRANSMISSION - NV4500 - SERVICE INFORMATION

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