Diff lockers

Out of curiosity... what set-ups have you got with diff locks? I think putting one in the rear would be beneficial in the mud! How much am I looking to spend? Are they worth it? - for the cost?
Thanks in advance!

There are various options from air lockers to helical lsd to mechanical unlocking ones and even spools. They range from a few hundred pounds to over a thousand for an air locker plus compressor. For off road I would suggest an air locker and for road a helical.

The way you use your Jiimny may also factor. If its used on road as well and you and you want the best off road performance, then the air locker is the way to go. The sad bit is they are expensive, but it does not alter the characteristics of the Jimny during road uae.
Full mechanical lockers can take a bit of getting use to on road, so make sure they are for you if you go this route.

If I was to go locker I would start saving for the air system, but thats just my preference. 

You can buy an arb copy made in china 
Called an HF air locker for around £500 

I have a Quaife limited slip diff. It cost around £700. For day to day driving and normal off-road it's great. It's always "on", giving more traction on loose/slippery surfaces and a more planted feel when pushing hard on the road. But it stops working as soon as a wheel lifts off the ground so it's not the right choice for extreme off-road like pay and play.

If your Jimny is for off-road with no daily driving I'd seriously consider a spool or welded diff. Spools are £160. They are cheap and 100% effective. The cheaper "auto lockers" (Lockrite) tend to be a bit unpredictable, often locking up mid corner. I'd rather taking a corner knowing my diff was locked than wondering if/when it was going to lock. It's worth reading some writeups from people that have actually driven vehicles with welded diffs, not just the opinions of people who have never tried it but think it will be awful.

A Kaiser locker is a more expensive, better engineered version of the lockrite locker. The problem with any auto locker is that in a turn they send all the torque to the inside wheel. Compared to an open diff that always splits the torque equally between both wheels, this means that the auto locker has doubled the amount of work that  the one wheel it's sending power to is doing, and therefore it massively increases the chance that it will spin. When it spins the diff locks and you find yourself cornering on the road with a locked diff.

Air lockers are expensive and an all or nothing option. Without it engaged you have a standard open, spinny diff with no traction advantage. When it's locked it's locked. They are the most expensive and the most involved to instal, needing a compressor to activate the diff.

Another option is the electric locking LSD diff. Made by a company called something like Extreme Dakar 4x4, it combines the everyday traction advantages of a limited slip diff with the ability to completely lock it should you need to. This seems to be the best of all worlds. It is under £700 and installation just requires a switched 12v feed to the diff.

 

I fitted an Eaton Tru-Trac unit to the rear axle of a Land-Cruiser 70 series. Normal driving on a sealed surface was improved in so much as cornering under power was tauter and more predictable. To test the unit I parked the motor half on a wet grassy area adjacent to a country road and in two wheel drive drove off under full power . There was no spin with the wheel on the grass, just hard acceleration. Same on a track, just exactly what you want. If you do lift a wheel, a quick yank on the hand brake will activate the system and off you go.

So, in summary, the unit is not overly expensive, it is easy to fit, it does not require special oils and it will transmit approx. It's fit and forget and because it does not lock up solidly the action is smooth and predictable. I drove approx. 100,000 miles with it and never had a problem. It can also be fitted in the front axle for ultimate traction.

Roger