Lockers:
As of 24 July, 2006, Locked Drive Systems did not make a locker or limited slip for the front axle of the FG.
As mentioned, the rear is a factory limited slip.
I did not pursue having a custom axle/differential made for either the front or rear due to worldwide parts and availability requirements for our utilization.
Tires:
I lost a lot of sleep worrying about the tires. I did a lot of research.
I've got a comparison page of the options at:
http://www.hackneys.com/mitsu/docs/yokohama-michelin-comp.pdf
Links to manufacturer's data sheets here:
http://www.hackneys.com/mitsu/index-chassis-photos.htm
As of Spring 2007 sourcing the Michelins new in the U.S. was a challenge. I was planning on shipping them over from the U.K.
We had a good thread regarding the FG tire discussion over on ExCamp, but the link is currently dead.
http://www.expeditioncampers.com/php...opic.php?t=237
Based on my rough measurements, there will probably be some clearance issues in the front if you go with the larger tires. Almost certainly with the plastic trim piece that forms the outer fender trim and possibly the steering link on the driver's side. Nothing that you can't overcome.
In the end I stayed with the stock tires and run a little more pressure due to our weight. I am trading some ride quality and tread wear for the convenience of the stock size.
We're at 16k miles and tread wear is good.