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Lokka diff into the front of an R50


Nickj
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Hey all

 

This install is for Australian vehicles, OS models maybe slightly different.

 

Finally Santa bought me something useful - an LR86 Lokka from 4WD Systems! Due to a late order and Christmas, it did arrive a little late - on 9/01, it was ordered before Christmas. So, I went to work on the installation, thanks to GEOFF57 and JOHN from PCOA forum for much assistance during the process. Didn't think you would be asleep at 2:30pm though Geoff, sorry.

 

Check list: Check to make sure your kit included 2 x side gears, 2 x cam gears, 4 springs, 4 small pins, 2 spacers, a replacement cross shaft (the one that used to hold in the spider gears). The names I have used above are how they are described in the documentation you receive from 4wd Systems. You will also need a good socket set, torque wrench, feeler guages, a long bar used to keep the assembly still while you loosen bolts, about 1m of fencing wire or a wire coat hanger, a pot of grease, some locktite, a permanent marker, a long thin pin punch, a copy of the required torque settings, a large vice to hold the carrier firmly in and a big trolley jack. Most of all, read and understand the instructions provided, along with the ones that Geoff57 provided.

 

So, where do I start? I drove my car on to car ramps and laid some canvas on the ground as I don't have the luxury of a concrete space to work on. Chock the rear wheels so it doesn't slip backwards, vehicle in PARK with the handbrake firmly applied.

lokka1.jpg

Car on ramps

 

Before you undo any bolts, mark the following with a permanent marker:

lokka2.jpg

Front coupling of Tailshaft

lokka3.jpg

Both left and right hand CV joint couplings

 

You can start undoing bolts now to remove the front diff assembly. This order would be best one to follow, if you don't follow it, you will possibly have to put some bolts back in to undo others :oops: .

 

4 x 14mm tailshaft nuts/bolts, these were the tightest bolts I have ever had to undo! If you have Free Wheel Hubs, you will need to lock them up now to keep the front tailshaft still. If you undo 2 nuts, then unlock the hubs, rotate the tailshaft 180deg to expose the 2nd 2 nuts, then lock the hubs again. If you don't have FWH, you may need to lift one side wheel to enable you to rotate the tailshaft. DO THIS CAREFULLY! Once you have all 4 nuts/bolts removed, push the tailshaft yoke upwards and support it with some wire from somewhere in the engine bay so it doesn't hang down and get in the way.

 

The CV joint couplings, there are 6 x 12mm bolts in each one, you will need to lock/unlock FWH as per above to rotate the CV joint to expose all 6 bolts. The clearance will only allow you to do 2 at a time. Do 2 on one side, then 2 on the other side, then rotate them to expose another 2 on each side. Once all bolts removed, you can just push the CV joints back towards the wheel for some clearance.

 

lokka11.jpg

There's 4 x 17mm bolts each side of the chassis that attach the assembly to the front of the car. Japanese must have some great spanners, or maybe they did this before mounting the front end in the vehicle! :? Leave one lower bolt each side loose but not removed, the front end will hurt when it lands on your chest or legs! The top bolts are a little hard to get to, thats why I suggested leaving a lower bolt still attached.

 

lokka5.jpg

Take the weight off the 2 remaining bolts with the trolley jack and some big bits of wood. Looks dangerous, but with 2 of you its ok, the right hand side of the assembly is heavier so concentrate your friend in suppoirting this end, while the jack will support the centre and the short end. With the assembly supported, you should be able to remove the last 2 bolts carefully. Lower it a little to expose the front breather, as you still have to disconnect it from the front cover. It will allow you to drop the housing about 6-8 inches (sorry 150 - 200mm) before you remove it. Now with your friend carefully supporting the right hand side of the housing, lower the trolley jack till it is on the ground. Relocate the whole assembly to the workbench.

 

lokka7.jpg

Drain the oil (nearly 2 litres) into a clean container, clean and remove the cover to expose the good stuff!

 

There's a 14mm bolt holding he short side shaft in, and 4 x 12mm bolts holding the long one in. Once removed, check the condition of the bearing on the long side shaft, mine looked ordinary as there must have been some moisture in there sometime... :wink: I replaced my bearing and grease seal before I reassembled it.

 

lokka8.jpg

Before disassembly, mark the crown wheel/carrier and both bearing caps so you can put them back in the same place, the same way around. You can now undo the 2 x 2 x 17mm bolts holding in the bearing caps, out will come the carrier with bearings attached, 2 bearing cups and 1 shim on each side. Keep these parts in order so you can replace the same way around. Then, with the carrier assembly standing vertical on the bearing with the crown wheel at the top, undo all the 17mm bolts around the crown wheel. Carful when you do the last one as the crown wheel will drop down onto the bench. :o

Inspect the bearing on the longer side shaft as mine looked a bit ordinary. here must have been some moisture inside and the bearing didn't look right to go back in. For the sake of $30, just do it.

 

Remove the roll pin from the carrier and remove the cross shaft, this will enable you to remove the spider gears and associated shims. You may need to rotate the carrier whilst removing the spider gears. Keep the shims that were under the spider gears that the side shafts go into as these will be required later.

 

Time to put the new bits in. The side gears, spacers and the shims can go in now, apply a liberal amount of grease to them to hold them together and in the carrier during asembly. Now insert the cross shaft and measure between the spacer and the cross shaft on each side. This should be between 0.006" and 0.020", if not, shims will be required to get this within tollerance. Now, locate the small pack of 4 pins and 4 springs that came with your Lokka. With some grease, place each of the 4 pins into the slot in the cam gear with the nipple facing the cam that the pin is in. Remove the cross shaft and put the crown wheel side cam gear with pins greased in into the carrier aligning the teeth with the corresponding side gear. Locate the short side shaft lock nut and with this loosely inside the other side cam gear, insert it into the carrier and align teeth with the side gear.

lokka9.jpg

The cam gears have flat sides to enable assembly. With the 2 cam gears in, it's time to inser those springs into the cam gears. With a small screw driver, slide the small pins into the opposite side cam gear, make sure the nipple on the pin is visible. Place the spring into the slot, compress it with the small screw driver and make sure it is located both around the pin nipple and into the cam gear. Do this for all 4 springs. Now you cam measure the assembly for clearance between the 2 cam gears. This should be between 0.125" and 0.165", this is critical for correct Lokka operation. If not correct, shims will need to be removed or applied, these should be available from a gearbox rebuilder.

 

Grab the short side shaft and insert it into the correct side and align the spines with the side gear. Insert the retaining bolt and pick up the loose lock nut inside the assembly and tighten it up a little, ensuring the lock nut is aligned inside the side gear splines. Just tighten it enough to secure it during assembly, then remove the bolt. Fit the crown wheel back onto the carrier and torque the bolts up to 98-112 ft/lb, use some Locktite on the threads. Refit the whole carrier assembly into the housing along with the bearing cups and shims in the correct order. You may need to rotate the carrier to ensure it meshes correctly with the pinion gear. Put the bearing caps on and secure the caps with the bolts making sure of correct alignment. Torque the bolts to 65-72 ft/lb, use some Locktite on the threads.

Refit both side shafts and secure to the correct torque, greasing both seal surfaces. When doing the long side, apply some silicone to the flange to ensure a good moisture seal. Torque all bolts up to correct spec. Short side - 23-31 ft/lb, long side flange - 25-36 ft/lb.

 

Refit the cover and torque bolts down to 33-40 ft/lb. Put the asembly on its end with the oil filler plug at the top, remove the plug and refill the oil. Get your friend's finger to plug the breather hole before you fill it!

 

Now to put back in the vehicle, a reverse of the removal process.

 

lokka10.jpg

Make sure you refit the breather, if you were planning on extending it, now is the time. Don't forget to correctly align the CV joint and tailshaft couplings to their original location. Tighten all bolts to the correct spec.

 

lokka12.jpg

Spare parts? If you have more than this left over, you are in trouble!

 

**NOTE** Once assembled, there is some backlash when turning the tailshaft either way. It seems excessive, but this is necessary for correct Lokka operation.

Also, while turning sharply on bitumen with the hubs locked, there is a clunk clunk clunk sound from the front. This is normal too, but 4WD Systems do not recommend hubs to be locked on bitumen. I don't usually have them locked anyway, but worth a mention.

 

Pre drive testing. Lock the hubs and select 4H, raise one wheel and try to rotate it in a forward direction. This is to test the unlock function of the Lokka. I needed some extra leverage so I used a long extension bar and wheel nut socket. Do this on both sides of the car. If it does not unlock, do not proceed. Remove and check all components and tollerances. Mine was good.

 

Time for a drive test. There's a gravel dump near our house. Approaching at the right angle got a rear and opposite front wheel off the ground and in 2WD, this is as far as I got. Now lock the hubs and into 4L, the car kept climbing till I was uncomfortable 1.2m off the round on top of a pile of gravel!!! We reversed back down to safety. We then approched a 40cm high embankment on the side of the road and went up on angle, it just climbed up onto the embankment! What will this car not do now? (travel in deep ruts! :( )

 

Anyway, it did take a little longer due to the cross shaft not being sent with mine, but Tom at 4WD Systems was good to send Express Post and it arrived the next day.

 

http://members.dcsi.net.au/hilltops/Lokka.pdf

http://members.dcsi.net.au/hilltops/R50_Lokka.doc

I have also attached Geoff's notes above and an exploded view of the diff assembly from the Pathfinder manual.

 

$600 well spent I say, screw the snorkel......

 

 

Nick

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Very Nice!! :clap:

 

Thank you for taking the time to write and post that. I am going to pin it in the appropriate model section and leave a link here.

 

Next we need to see pictures of what she can do now... ;)

 

B

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Huh... I do that sometimes too. Due to the free wheel hubs being unlocked on the road, it's no different. Once you are on the track though, the hubs locked and in 4H or 4L, when accelerating even slightly, it really tries to pull the steering wheel straight. This is due to both front wheels trying to turn at the same time. It's something you get used to very quickly. Get a wheel off the ground and you can just crawl out of it!

 

Nick

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  • 3 months later...

Now with pics.

 

easter101.jpg

My 17yr old daughter driving up a 30cm rockledge

easter108.jpg

Daughter again climbing up some rocks working the Lokka hard!

 

Nick

Edited by Nickj
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IMHO, combined with a highly sprung rear LSD, this is the best bang for buck in the performance stakes. I need to highly spring my rear LSD.

 

Nick

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This a great upgrade to our R50

 

This front lokka is a project a hope to tackle in

a near future.

 

And for the rear diff, it would be great if someone do

a thread on that.

 

I didn't know we could add strengh to our rear LSD

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  • 4 months later...
  • 4 years later...

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