4WD System's Front Lokka in a D22

The following is a DIY article for installing a front lokka in a 2006 navara R180 Differential.


The unit comes with instructions for the installation and according to 4WD systems "it can be installed by anyone capable with simple mechanical work in one to four hours. In these cases, no special setup is required since the crown wheel and pinion gears are not upset. No special tools, calibration equipment or expensive diff specialists are required just an installation manual and basic tool kit. Once referred to as the "45-minute locker", it can generally be fitted by the average do it yourself person capable of fitting brake pads."

I aim to put this to the test as I'm not a mechanic and have never disassembled a diff before..... but I can change brake pads . Now I've done a fair bit of research first and have put together all the necessary items I feel will get the job done. Here is my "basic" tool kit for the install:

Tools:
Socket Set
Torque Wrench ($69.99)
Feeler Gauge ($6.50)
Dial Indicator ($39.00)
Trolley Jack ($59.99)
Car stands ($26.39)
Wheel Chocks ($6.59)
Breaker Bar
Tie wire or string
Metal punch
Large Vice

Materials:
Lokka ($520)
Instructions
D22 service manual
Gear Oil 1.3L EPX 80W90 or similar ($35.95 4L)
Threadlock ($12.88)
Instant Gasket ($12.99)
Grease
Permanent Marker or Whiteout
Friend to help hold things
A few cold beers

Approximate cost for everything so far: $730.29 (A lot less if you already have the tools)

Here are some of the required items






This is what comes in the LR-89 lokka kit


2x Spacer rings
2x Axle gears
4x Springs
4x Pins

To be continued on saturday when I begin the install. Testing will be conducted the following weekend at LCMP.

subscribed!!!

As soon as I saw feeler guages on the menu I figured i'd leave it to the pro's

Hi guys, well I've finally fitted the lokka. It was a mission for one person so make sure you have a friend to help. It took me 12 hours total to take out the diff, install the lokka and put it back in! Without a good socket set ( Busted a cheap one before using a better set) and vice be prepared for a long haul. So far so good, there is no harsh metal grinding and im still able to steer so all has gone well for now. The write up will be posted tomorrow if im not busy at work.

12 hours?
I think the torque steer issue will only reveal itself in 4WD.Anyway Glad to hear it's all done and your happy so far. I'm looking forward to your write up.

good job getting it in Joe. 2 hrs or 12 hrs - doesn't matter once you've completed a job like that. And I bet you learnt heaps while doing it. Let everyone know how it goes at LCMP

DVR said:

12 hours?
I think the torque steer issue will only reveal itself in 4WD.Anyway Glad to hear it's all done and your happy so far. I'm looking forward to your write up.

Click to expand...

Yeah will only affect driving when you lock the front hubs in, the only place I can see the lokka's being a little bit annoying is on a fast dirt road. I would probably leave it in 2wd more often than not if I had one in the front as I think it would affect the steering quite a bit around corners. Looking forward to hear what Joe has to say about it after a thorough test.

Here it is finally a step by step guide to fit a front lokka:

Step One:
On a level surface, in gear, apply the handbrake, chock the rear wheels and using a quality jack raise the vehicle and place appropriate car stands under the chassis rails.



Step Two:
Once safe to work under, remove the front bash plate to access the diff. There are 6x 10mm bolts and two plastic clips either side (These can be removed by squeezing the tabs and pry with a flat screw driver). Keep all parts in clear plastic zip lock bags and mark on them where they came from, it is also helpful to photograph all steps so you can refer back to them if in doubt.



Step Three:
Mark with a metal punch if possible the position of the tailshaft as I only used a permanent marker and some lines almost rubbed off. Lock in the hubs and undo the 4x 14mm bolts of the front tailshaft. You will have to undo two at a time and then reposition the tailshaft by unlocking the hubs then rotating and re-locking again to reach the final two bolts. These bolts and every other bolt for that matter are tight so is pays to use a quality socket and wrench sets. Then tie the tailshaft up and out of the way.





Step Four:
Next it’s time to undo the left and right CVs. Also mark their positions and with the hubs in free wheel, spin the CVs to an appropriate spot to undo two bolts on either side. Then lock the hubs in to stop the CVs moving while you undo the bolts. Just like the tailshaft you will have to unlock and re-lock the hubs to access all the bolts. There are 6x 12mm bolts in each CV. Once they are undone tie out of the way.

Step Five:
Next it’s time to drain the diff oil. There should be around 1.3L. I found it easier to remove the diff breather at this time then the filler plug to let air into the diff when draining. So to remove the breather squeeze the metal clip with pliers and move it up the hose and out of the way then with pliers and a flat head screwdriver ply the hose off.



With a catch pan underneath, undo the drain plug on the bottom of the diff with a ¼ inch socket wrench. Let the oil drain completely then fit the plug again loosely. The picture below is of the filler plug.



Step Six:
To remove the diff now requires the front and rear cross members to be unbolted. Place a trolley jack underneath the diff and raise it up to support the diff when the bolts are taken out.



Remove only three 19mm bolts of the front cross member for now. Next remove the two 17mm bolts from the rear cross member. With the help of a friend lower the jack while balancing the diff and swing it to the ground. It may take a little persuasion to drop down, now remove the final bolt.

Step Seven:
Place the complete diff on a work bench and remove the front cross member completely.



Step Eight:
Place a positional mark and take off the long axle by undoing 4x 17mm bolts and break the gasket seal. This will need gasket goo when re-installing. Slide off the axle.



Step Nine:
Time for the good stuff. Place the diff in a strong vice with the rear cover facing up. Mark the cover and remove the 8x 14mm bolts and pry the cover from the housing.



Remove the metal gasket (I used gasket goo again to seal this on re-installation). Now check the backlash between the crown wheel and pinion gears. To do this you will need to use a dial gauge in a mount. Place the needle of the gauge 90° to the face of the ring gear teeth, Hold the companion flange at the bottom steady to keep the pinion gears from moving and rock the crown wheel back and forth. Record this distance of movement, rotate the wheel 90° and measure again do this another two times. The movement should be even at all sides and be between 0.008” and 0.016”. Mine was 0.009” so within the tolerances.



Step Ten:
It is now time to remove the carrier. First though the axle bolt on the short axle side has to be removed. Hold the differential side flange in the vice and undo the 14mm bolt.

Next the two side retainers must be taken off to remove the carrier assembly. Mark these with the punch and undo the 5 bolts (Do not over tighten these when re-installing as they can be easily sheared).



Pry them off gently to avoid damaging the metal gaskets (These gaskets are used again). Also make sure to hold the carrier as it will fall when removing the side retainers.



Now remove the carrier assembly.



Take care not to damage the end bearings as well.

Step Eleven:
Do not remove the Crown wheel from the case as it will not interfere with the installation of the lokka. I made this mistake and it was just a pain in the ass because these bolts are tough and I mean they needed a 4ft steel bar to lever off. Place the carrier in the vice and undo the 8 bolts holding the two sides together (these are also tight). Separate the two halves.



Step Twelve:
Remove the cross spider, gears and washers. Examine the spider for any wear or damage, replace if needed. Remove and retain the thrust washers from the base of the side gears. Remove the axle retainer nut from the non-crown wheel side axle gear. You will need to tap it out of this gear and retain for later use.

Step Thirteen:
Fit an axle gear and thrust washer into the crown wheel side of the carrier, spin to make it settle. Position the spacer ring over the axle gear. Place the cross spider into position. With a feeler gauge measure the gap between the cross spider centre block and the top of the spacer ring. This gap should be between 0.006” and 0.020”. Mine was not right but I hadn’t put in the thrust washer that came with the lokka as well. I fitted this and the gap was perfect at 0.008”. Next do the same with the non-crown wheel side; the gap for this side was 0.006”. Record both of these measurements. As they are within the variations the lokka is symmetrical about the cross shaft. Maximum variation is 0.010” between the measurements.

Step Fourteen:
Put grease into the holes and teeth of both lokka cam gears. Fit a spring into the deeper holes (2 per cam gear) and a pin with the nipple exposed in the shallower holes (2 per cam gear).





Locate one cam gear onto an axle gear in the carrier. Do not fit the spider. Position the second cam gear onto the first, align the pins and springs and push down a few times to make sure they are located and everything moves freely. Position the second axle gear and thrust washer onto the second cam gear and seat the other carrier on top. Bolt this together using two or three bolts only. Make sure the lokka gears are meshed.

Gain access for the feeler gauges through the casting and lever the gears apart with two screw drivers and measure the maximum distance. Withdraw the levers and measure again and record both measurements. Average the two gauge measurements. I got 0.150”. This measurement should be between 0.145” to 0.165”. If not the thrust washer may have to be machined.



If within the tolerances disassemble so the spider can be fitted for final assembly.

Step Fifteen:
Now fit the axle retainer nut to the non-crown wheel side lokka axle gear. Make sure to align the old spline marks up with the axle gear splines and press/mesh forcefully into the gear. It must seat fully so that is does not interfere with the spider.

Grease everything and reassemble the carrier as before but with the spider in place between the cam gears. Check that the retainer nut does not interfere and the springs and pins are aligned. Also check that the gears are meshed and now you can tighten the 8 bolts again with locktite applied, to a torque of 64-74 Nm using a torque wrench.



Check the gap again and record this measurement.

Step sixteen:
Place the carrier assembly back into the case exactly as before. Fit side retainers and gaskets and bolt to a torque of 9-12 Nm.



Replace axle bolt (31-42 Nm) and check backlash again. The backlash should be the same as before disassembly. Clean the gasket surface, re-apply gasket and replace cover and bolt to 39-49 Nm. Fit long axle shaft gasket and bolt to 88-98 Nm. Bolt on front cross member to 68-87 Nm.



Remove filler plug and fill diff with 1.3L of recommended diff oil. Use locktite and re-fit filler plug to 39-59 Nm. Time to re-install the differential to the Navara.

Step Seventeen:
Place diff on jack and with the help of someone else raise into position. This is a little tricky and requires patience. Fit a top bolt of the front cross member and jack up evenly you may have to hold the CVs out of the way until more bolts can be put in. Once all the bolts are in, tighten them to 68-87 Nm. Re-install diff breather. Re-install CVs to their positions and tighten the bolts. Lastly re-attach the drive shaft. Re-fit bash plate.

Step Eighteen:
Unlock test: Before road testing lock in the hubs and put the transmission into gear so the tail shaft cannot rotate. With a friend hold one wheel back and rotate the opposite wheel forward. A slight ticking noise should be evident. Rock the first wheel forward and the second back, again the noise should be evident. Repeat this for the opposite side. If it unlocks in all four situations then it is ready to be road tested.

Road test: First test drive with the hubs unlocked and in free and in 2WD. Now lock the hubs and drive in 2WD. The ticking will be less evident than in the previous test. There should be no change in the steering. On an appropriate surface lock the hubs and engage 4WD. Steering will feel a little different and self-centre rapidly. Do not drive in 4WD on a hard surface. You are now all finished!! Enjoy!

The best detailed "how to" I have seen, well done.

I've replaced/rewired engines in cars before, but diffs seem to be a bit scary. Would have cost you a fair bit in labour to get someone to do it, so theres a good saving straight away!


Hoo Roo

Well done mate, great write up.

Dave.

yeah thats an awesome how to good job mate. Let us all know how you rate it when you start driving around.

that is great, you've gone to a lot of extra effort. thanks. also keen to know your opinions on how it drives as its something i've considered then dismissed.

awesome write up!!
i will definately be using this when i put mine in (when it bloody gets here after nearly 2 months!!)
Cheers, James

It is the best mod i've done to the navara so far I love it!

Thanks It all seems so much clearer now ..

By the way !! Did I see your Nav at the shopping centre on Manly Rd