I just lost 5th gear in my NV 4500 (wonderful Christmas present)...what are my choices...New trany...rebuild tranny...live w/o 5th...I don't have a much $ right now, so I am looking for the best priced option for now.

Any help would be appreciated.

 

When I lost my 5th gear, I dropped the transfer case, pulled the rear housing and put it all back together with thread locker. It never came loose again. Some will say that is a good fix, while others weld the nut or use some special type of nut. Most will probably say that this is a temporary fix and the only permanent solution is to get an updated mainshaft to fix the problem. Either way, you will temporarily have your 5th gear back if you just tighten the nut...for a few thousand miles anyway. Just make sure you have the correct oil to put back in the tranny and the special tool needed to tighten the 5th gear nut.

 

Thanks Andy.

 

When mine came off, i put the nut back on (which was the updated nut) with tread locker, set the screws on the nut and tack welded it in 4 spots. My reasoning behind it was if it comes off again, i needed to do the fully splined mainshaft update anyways. LOL

 

you can do it while tranny is still in truck just be careful not to strip one of the tailshaft cover bolts I believe they are 12 point or something like that?
search here and TSB's the nut is not that expensive and its not that bad of a job I followed, I think, the instructions from genos garage.
good luck like Andy505 said make sure you get the correct fluids ect

 

Yeah, I have always repaired them with the updated nut and haven't had any come back. One secret is to make sure the gear still has an interference fit onto the shaft. If the splines fit loosely, you need to use a new gear. If the new gear still fits loosely on the shaft's splines, you'll need a new shaft too, or you will just have to be aware that it isn't a permanent repair.

 

Thanks for the info guys. Took the truck to the shop on Wed. morning and they put on the updated nut. Said everything looks good and should not have problems.

 

Here's the TSB with part numbers
Happy New Year!

NO: 21-10-98 Rev. A
SUBJECT: Loss Of Fifth Gear
DATE: Sep. 25, 1998
THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 21-10-98, WITH AN EFFECTIVE DATE OF SEP. 11, 1998, WHICH SHOULD BE REMOVED FROM YOUR FILES. ALL REVISIONS ARE HIGHLIGHTED WITH **ASTERISKS** AND INCUDES ADDING THE 1999 MODEL YEAR AND A NEW PROCEDURE TO INSTALL THE FIFTH GEAR NUT.

NOTE: THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH A NV4500 MANUAL TRANSMISSION AND THE 8.0L V10 GAS ENGINE OR THE 5.9L CUMMINS DIESEL ENGINE.

SYMPTOM/CONDITION:
Transmission operates normally through all ranges except fifth gear.

DIAGNOSIS:
Depress the clutch, start the engine, then shift the transmission into fifth gear. Slowly release the clutch to verify that the vehicle can move (or engine rpm drops due to the load applied to the engine) with the transmission engaged into fifth gear. If the vehicle does move (or engine rpm drops due to the load applied to the engine) with the transmission engaged into fifth gear, the vehicle will need to be road tested. If the vehicle does not move (or engine rpm does not drop when the clutch is released) with the transmission engaged into fifth gear, perform the Repair Procedure.

Road test the vehicle on a road that will allow you to operate the vehicle safely in fifth gear. If during the road test, the transmission pops out of fifth gear or fifth gear cannot be obtained, perform the Repair Procedure.

PARTS REQUIRED:
Qty Part No. Description
1 04741551 Gear, Fifth
1 05013887AA Nut, Clamp, Package
1,Clamp Nut Assembly
1,Spring Disc Washer
1,Loctite #272 (Mopar p/n 05014205AA)
1 04897150AA Cleaner, Mopar Brake Parts
4 04874459 Lubricant, Mopar Manual Transmission
1 04318031 Adhesive, Mopar Lock & Seal
1 04318083 Maker, Mopar Gasket


REPAIR PROCEDURE:
This bulletin involves installing a new fifth gear, spring disc washer, and a revised fifth gear clamp nut.

Shift the transmission into neutral.
Raise the vehicle on an appropriate hoist.
If equipped, remove the skid plate.
Place a drain pan under the transmission.
Remove the PTO cover bottom bolt and drain the lubricant out of the transmission (Figure 1).
Using a suitable marker, mark a line across the rear axle pinion yoke and the rear propeller shaft yoke for installation reference.
If equipped with a two-piece propeller shaft, with a suitable marker, mark the outline of the center bearing on the frame crossmember for installation reference. Then, remove the bolts that attach the center bearing to the support bracket (Figure 2).
Remove the bolts holding the universal joint clamp to the pinion yoke.
Slide the slip yoke off the transmission/transfer case output shaft and remove the rear propeller shaft. If the vehicle is a 4X4, proceed to Step 10. If the vehicle is a 4X2, proceed to Step 21.
With a suitable marker, mark a line across the front propeller shaft yoke at the transfer case and the propeller shaft yoke at the rear of the front propeller shaft.
Mark a line across the propeller shaft yoke at the front of the front propeller shaft and the front pinion shaft yoke.
Remove the universal strap bolts at the front pinion shaft yoke (Figure 3).
Remove the bolts holding the propeller shaft to the transfer case yoke flange.
Remove the front propeller shaft.
Disconnect vent hose and vacuum harness at transfer case switch.
Disconnect transfer case shift linkage at transfer case range lever. Then, remove transfer case shift mechanism from transmission.
Support transfer case with transmission jack. Secure the transfer case to the jack with safety chains.
Remove transfer case attaching nuts.
Move transfer case rearward until transfer case input shaft clears transmission output shaft.
Lower transfer case assembly and move it from underneath vehicle.
Support the transmission with a jack.
Remove bolts attaching transmission mount to the rear crossmember.
Remove bolts attaching exhaust pipe hanger to the transmission.
Remove the eight bolts that attach the extension/adapter housing to the gear case (Figure 4).
Remove extension/adapter housing.
NOTE: THERE IS ONE ALIGNMENT DOWEL IN THE GEAR CASE AND ONE IN THE EXTENSION/ADAPTER HOUSING.

If equipped, remove rubber spline seal from end of mainshaft (Figure 5) and discard. The seal is mainly used to prevent lubricant loss during shipping and does not have to be replaced.
Install nut wrench special tool 6743 onto fifth gear nut (Figure 6). Be sure wrench is fully engaged in nut slots and is not cocked.
NOTE: THE NUT WRENCH WILL ONLY FIT ONE WAY ON THE NUT.

Position the small end of the nut wrench at approximately the 10 o’clock position (Figure 6).
Install splined socket Special Tool 6993 (4X2) or 6984 (4X4) onto the mainshaft. Then, install a breaker bar onto the splined socket. Wedge the breaker bar so that the mainshaft cannot turn while loosening the fifth gear nut (Figure 7).
Strike the small end of the nut wrench with a heavy soft face hammer to break the nut loose. During assembly, the nut has been tightened to 300 ft. lbs. of torque. In addition, it is secured by a an interference fit thread plus Loctite adhesive and will require several firm blows to loosen it. Once the nut is loose, it can be removed by holding the nut wrench with a breaker bar and rotating the output shaft with the spline socket and the breaker bar (Figure 7).
NOTE: THE NUT MAY ALREADY BE LOOSE AND WILL NOT REQUIRE YOU TO STRIKE THE NUT WRENCH TO LOOSEN THE NUT.

Remove the roll pins that secure the countershaft fifth gear shift fork to the shift rail with a pin punch (Figure 8). Drive the roll pins from the bottom of the fork and not the top.
Remove the snap ring that secures the fifth gear clutch hub and gear onto the countershaft (Figure 9).
Remove fifth gear shift fork, gear and hub, and synchronizer components as an assembly. Remove assembly by tapping shift fork off rail with a plastic mallet.
Remove countershaft fifth gear needle bearing assembly and the cone shaped rear bearing thrust washer from the end of the countershaft. Note the position of the washer for assembly reference. Also note that the washer bore has a notch for a retaining pin.
Remove and retain thrust washer locating pin from countershaft.
Remove fifth gear from the mainshaft using puller Special Tool Set 6444 and the following procedures.
Position first half of puller jaw Special Tool 6820 onto the fifth gear (Figure 10).
Assemble puller flange Special Tool 6444-1 and puller rods Special Tool 6444-3 for 4X2 models or 6444-4 for 4X4 models (Figure 11).
Slide assembled puller flange and rods onto output shaft. Then, seat flange in notch of puller jaw.
Position second puller jaw Special Tool 6820 onto gear and the notch on the puller flange.
Slide retaining collar Special Tools 6444-8 over puller jaws to hold them in place (Figure 12).
Install puller and bolt (Special Tool 6444) onto puller rods. Then, secure the puller to rods with the retaining nuts (Figure 13).
Tighten puller bolt to remove gear from shaft splines.
Clean the mainshaft threads with a wire brush.
Clean the mating surface of the extension/adapter housing and the gear case with Mopar Brake Parts Cleaner p/n 04897150AA.
CAUTION: THE REAR SEAL OF THE EXTENSION/ADAPTER HOUSING MUST BE PROTECTED FROM THE MOPAR BRAKE PARTS CLEANER WHEN CLEANING THE HOUSING’S MATING SURFACES.

Install new fifth gear p/n 04741551 onto the mainshaft. Use installer Special Tool 6446 to seat gear onto the mainshaft (Figure 14). Gear is seated when it contacts the rear bearing.
Clean threads of the new fifth gear nut (from package p/n 05013887AA) and the mainshaft with Mopar Brake Parts Cleaner p/n 04897150AA.
Install the new spring disc washer (from package p/n 05013887AA) onto the mainshaft. The concave side of the washer must be positioned toward fifth gear (Figure 15).
Apply the Loctite #272 (Mopar p/n 05014205AA) (from package p/n 05013887AA) to the threads of the nut.
**Carefully slide the new nut (from fifth gear nut package p/n 05013887AA) over the mainshaft splines up to the threaded portion of the mainshaft but do not engage the threads at this time. The flat side of the nut must face towards fifth gear and the concave washer (Figure 16).
NOTE: IF THE NUT DOES NOT SLIDE EASILY OVER THE MAINSHAFT SPLINES, LOOSEN THE CROSS BOLT IN 1/4 TURN INCREMENTS UNTIL THE NUT SLIDE OVER THE SPLINES.

Tighten the cross bolt until the gap in the fifth gear clamp nut assembly is closed.
Back the cross bolt out one full turn.
CAUTION: THE ABOVE STEPS ARE CRITICAL FOR THE FIFTH GEAR CLAMP NUT TO FUNCTION PROPERLY.

Install nut wrench Special Tool 6743 onto the fifth gear nut.
Install splined socket Special Tool 6993 (4X2) or 6984 (4X4) onto the output shaft and attach a breaker bar to the splined socket. While holding the fifth gear nut with the nut wrench, tighten the fifth gear nut until the nut bottoms onto the fifth gear spring disc washer. Then, install a high capacity torque wrench onto the fifth gear nut wrench and torque the nut to 366 - 380 N•m (270 - 280 ft. lbs.).
Tighten the cross bolt on the fifth gear nut. Torque the bolt to 11 - 14 N•m (8 - 10 ft. lbs.).**
Install the fifth gear synchronizer thrust washer pin into the countershaft bore (Figure 17).
Install the fifth gear synchronizer thrust washer onto the countershaft. The flat side of the washer faces the rear of the transmission and the tapered side faces the front of the transmission (Figure 17). Turn the washer until the pin engages into the thrust washer notch.
Lubricate the fifth gear needle bearing with gear Mopar NV 4500 Transmission Lubricant p/n 04874459 and install the bearing onto the countershaft.
Install fifth gear shift fork, gear and hub, and synchronizer components as an assembly onto the countershaft and the shift rail.
Install clutch gear snap ring (Figure 9).
Align roll pin holes in shift fork with notches in the shift lug rail. Then, install roll pins from top side of the fork.
NOTE: ROLL PINS ARE DIRECTIONAL AND WILL ONLY FIT PROPERLY ONE WAY DUE TO A SMALLER SHOULDER AT ONE END OF THE PIN.

Verify that the alignment dowels in gear case and extension/adapter housing are in their proper position and are fully seated.
Apply Mopar Gasket Maker p/n 04318083 to the gear case and extension/adapter housing mating surfaces.
Align and install the extension/adapter housing onto the gear case.
Apply Mopar Lock N’ Seal p/n 04318031 to the threads of the extension/adapter housing bolts.
Install and tighten the housing bolts to 54 N•m (40 ft. lbs).
Continue reassembly procedures using Step 1 through Step 23 in reverse order.
Once the transmission has been fully assembled, fill the transmission with 3.78 liters (8 pints) Mopar NV 4500 Transmission Lubricant p/n 04874459
POLICY:
Reimbursable within the provisions of the warranty.

TIME ALLOWANCE:
Labor Op. No. Description Time
21-36-02-90 Fifth Gear Nut Removal And Installation - 4X2 2.5 Hrs.
21-36-02-91 Fifth Gear Nut Removal And Installation - 4X4 3.4 Hrs.


Optional Equipment:
Labor Op. No. Description Time
21-00-06-61 Skid Plate Equipped 0.2 Hrs.


FAILURE CODE:
Code Description
P8 New Part