Dodge Dakota 9 1/4

Lock-Right Locker Install

Installing a Powertrax Lock-Right locking differential

In a (C-clip) Dodge 9 ¼” corporate axle

By John McKinney

It’s a natural progression. We want to venture off the beaten path, so we buy a four-wheel drive vehicle. We turn off of the paved roads and start with mild trails progressing to more difficult trails. We start to notice our lack of clearance, so we go out and buy a lift kit and bigger tires. This helps, but it only makes us more daring, so we go out and try to conquer even more difficult obstacles. Well, when we find out that even with more ground clearance, if we have no traction we don’t get far. We start looking into traction aiding devices. We learn about such things as LSD’s, then we find out about these wonderful devices called lockers. There are several different types/brands of lockers, but for this article we will be discussing the installation of the Lock-Right automatic positive-locking differential, by Powertrax.

This article is only meant as a supplement to the manufacturer’s installation instructions. Please follow manufacturer’s recommendations. Hopefully, I can help clarify some things that are specific to the 9 ¼ inch axle and provide better pictures.

Lock-Rights, sometimes referred to as “lunch-box lockers” because of their simplicity, are very easy to install in differentials with C-clip axles, such as the Dodge 9 ¼ inch. I have installed these kits in as little as 1 hour. The kit basically replaces the spider and side gears on open differentials. NOTE: This kit CANNOT be used on axles with a LSD carrier. The new No-Slip locker by Powertrax has models available for use with these carriers. Their installation is basically the same according to Powertrax.

The kit consists of (2) Couplers (bottom center and left), (2) Drivers (right) w/ spacers (top center), (4) small springs, (4) large springs, (4) Shear Pins (all near top on manual), and (2) shims (not shown) for use on some models of the 9 ¼ inch rear axle (we’ll get to that). See Figure 1.

Figure 1

Before we begin the installation, SAFETY FIRST, so lets get those jackstands underneath the axle to safely support the vehicle and block the front end to keep it from rolling. Obviously you will want to inspect all parts to be installed or reinstalled for damage, or extreme wear. Now is the time to replace worn components, since you will have the unit apart.

Step 1 – Prepping the differential

Start by removing the inspection cover and draining the fluid. Try to clean the inside of the case as much as possible. Some of the newer 9 ¼ inch axles have magnets in the bottom (such as this axle out of a ‘98 Dakota) to attract small metal shavings produced during normal wear. Try to remove as much of the “metal” sludge that will be found around this magnet as possible.

Step 2 – Removing the spider and side gears

Next, remove the pinion-shaft retaining-pin. This is the small bolt that goes through the carrier into the pinion-shaft. See figure 2. After the shaft has been removed, remove the two gears that were on the shaft by rotating the passenger side wheel. This will force the gears to “rotate” out of the carrier. Be sure to remove the thrust washers with the gears. See figure 3. Next, push the driver’s side wheel into the housing sharply to gain access to the C-clip that retains the axle. See figure 4. Once the axle is fully pushed in, the C-clip needs only to be rotated and will normally drop right out. See Figure 5. Well, I said normally, so those folks who are best friends with Mr. Murphy from Murphy’s law, may need to pull in and out on the axle a few times in order for it to be removed. Once the clip has been removed, the side gear and thrust washer will be able to be removed and the axle will then be free to be pulled outward. See figure 6. Clean the thrust washer, it will be used with the kit. Repeat these steps for the passenger side. The carrier should now be empty.

Figure 2    –    Figure 3    –    Figure 4    –    Figure 5    –    Figure 6

Step 3 – Prepping the parts for installation

At this point let’s get things ready to be installed. Put one smaller spring inside each of the larger springs, a little grease will hold them together. Coat the teeth of the Couplers and Drivers, the inside of the Drivers, and both sides of the thrust washers with grease. Put some grease in both of the larger “window” holes in each of the drivers. Put a shear pin in each of the “window” holes (two on each driver) of both drivers, the grease will hold them in. See figure 7.

Figure 7

Step 4 – Assembling the Lock-Right.

Install the driver’s side (ring-gear side) coupler (with the thrust washer) over the splines of the axle. Make sure the axle is pushed all the way into the housing so you’ll have clearance to install the C-clip. See figure 8. Install the C-clip with the round part towards the top and the ends pointing down so it will not fall out if the axle gets accidentally pushed back in. Sharply pull the axle out to seat the C-clip. Now, slide the passenger’s side Coupler onto the axle splines, but do not install the C-clip. Slide out the passenger side axle just far enough so that the end of the axle shaft is flush with the Coupler surface. At this time we want to take the small spacers and insert them into the center of the drivers. The spacers should be installed with the machined countersunk area facing the same way as the Driver’s teeth, and the flat side will be facing the center of the differential when installed.

Figure 8

NOTE: This is where you will need to know whether you will need to use the shims that were provided in the kit. You need to determine if you are working on a newer (thicker C-clip) or older (thinner C-clip) axle design. From approximately 1984, Dodge started to change to a thicker C-clip design, but both have been found up until about 1987. Powertrax states that the newer (thicker C-clip) versions have a “X” stamped into the case at about the 3 O’clock position on the cover mounting surface. I have never seen this and I was not able to find this on my ’98 axle, but I did have the thicker C-clips and DID NOT need the shims. I DID have to use the shims on my 1974 Ramcharger 9 ¼ inch rear end. You can determine this for sure by installing the Shims into the Spacers and if the Pinion-shaft is able to be installed past the axle shafts, you had the older style and needed the shims. If the Pinion-shaft will not install past the axle shafts, you DO NOT need the shims.

Now, take one of the Drivers with the Spacer installed in the center and mate it’s Teeth to the Teeth on the Coupler of the driver’s-side, the grease will help hold it in place. Push the Spacer in the center of the Driver toward the C-clip as far as possible. Now, with the end of the passenger-side axle still flush with the Coupler surface, install the passenger-side Driver (with Spacer in the center). Be sure to install the Driver with the “slot” facing you. See figure 9. At this point you’ll probably need a flashlight to look into the “slot” on the passenger-side Driver. You need to gently bump the axle in just enough to line up the groove in the axle itself with the “slot” so you can slide the C-clip in through that slot and onto the axle. I found it easiest if I used a small screwdriver that was long enough to seat the clip. Bottom line: Use whatever works. Make sure the Spacer is not too far towards the outside (towards the tire) so that it would interfere with the C-clip sliding onto the axle (Powertrax recommends using a piece of wire that is bent, to push the spacer back towards the center if needed).

Figure 9

Step 5 – Completing the job

We’re on the home stretch now. Turn the passenger’s-side axle until one of the “window” (oval) holes with a Shear Pin lines up with one of the round holes from the driver’s-side Driver. Use a small screwdriver to push the Shear Pin into the hole of the driver’s-side Driver. Insert one of the Spring Assemblies into the “window” hole where to Shear Pin was, this will push the Shear Pin all the way into the driver’s-side Driver. Be sure that the Spring gets completely seated by pressing on the lower coils so it can’t work it’s way out. See figure 10 NOTE: Figure shows spring NOT completely seated. Repeat this procedure for remaining three Shear Pins and Springs. At this point, use your fingers to make sure Spacers are seated all the way against the C-clips so the Pinion Shaft has clearance to be installed. After the Spacers are seated, install Pinion Shaft and Pinion Shaft Pin, tightening it to spec. See figure 11. If Pinion Shaft cannot be inserted past the axle shafts, see note above on use of Spacer Shims. Axle shaft end play should not exceed .020 inch. Check with Powertrax if you want to perform additional checks. They can provide tolerance limits specific to the Lock Right parts.

Figure 10- Figure 11

Step 6 – Checking your work

Now that everything has been installed, let’s check the installation to make sure everything is operating correctly. With driveshaft free (neutral), rotate each axle to check for smooth operation and if the springs are working properly. Now as a final test, put the transmission in gear to lock the driveshaft. Next, have a helper rotate the passenger’s-side wheel (axle) in a forward direction until it stops and hold it. This side is now locked. Now, rotate the driver’s-side wheel in the opposite (reverse) direction. The Lock-Right should click as the Coupler attached to the axle rotates. Now have your helper rotate the same wheel in a reverse direction until it stops and hold it. Now, rotate the driver’s-side wheel in the opposite (forward) direction and again you should hear the clicking sound. Have your helper change sides and perform the same test. If your measurements and tests have been successfully completed the unit has been installed correctly and you are now ready to install the differential cover and add the required amount of fluid. If you have any questions or concerns about your installation, please contact Powertrax at 1-800-Lockers (562-5377). Powertrax recommends normal gear oil with no additive required. I use 75-90 wt., but you can use a heavier oil like 85-140 to minimize the clicking sound from the Couplers if you are in a warmer environment.

Driving Impressions

I have used this model of Lock-Right in both an automatic and a 5-spd manual transmission. When driving the automatic vehicle on the street, the Lock-Right is almost not even noticeable. If you try to accelerate too quickly in a corner you can get the unit to lock up, and you may hear chirping in the turn. This is the only time I have been able to notice a difference, other than off-road. The 5-spd is a different story completely. The manual transmission has no fluid coupling (torque converter) so it’s much easier to get the unit to lock up. Driving habits will have to be slightly altered in order to avoid certain mildly annoying characteristics of the locker. You’ll notice that if you drive slowly in first gear and make a turn (like in a parking lot) the vehicle will tend to “buck”. This is remedied by taking it out of gear around those types of turns and coasting through them. I do it unconsciously now that I have driven the truck a while with it installed. Overall, even with these little “quirks”, I love the unit and I’ve never had any problems with either axles I have them installed in. The added off-road capability they give you more than justifies the slightly different driving technique required.

Finally…

This is what your axle will look like when you’re ready to head off road with your newly installed Lock-Right locker. See figure 12. Happy off-roading and remember to Tread Lightly.

Figure 12

References:

Powertrax Lock-Right installation manual. Copyright 1995