In the world, that I wheel in it is about flex, not lift. I run 36 x 13.50 IROKS with four-inch springs, fender wells tubbed, fenders cut and I want to lower it more.
As far as using a D-44 axle up front, many people do, some keep the stock width and some cut them down. Strength is a wash between the D-44 and the Toyota 8".
Here is some good info on D-44 axles and how to cut them down.
http://home.4x4wire.com/erik/For the rear end you can get an 86-95 rear axle, they are three inches wider and another benefit is the bigger brakes. The third member from a 79-85 will fit the housing although it is not a strong.
Some use the T-100 or Tundra rear axles, they are wider then the IFS (86-95) housing and have a stronger third member.
The nice thing about the Toyota axles over the D-44/60 type rear ends is the drop-out third member. This is just my opinion.
You can also get wheels with less backspacing, allot of people run wheels with as little as two inch backspacing.
Diamond axles also make custom housings in any width you want. Pricy but well worth. You cannot beat the strength of the housing. Here is their web page.
http://www.diamondaxle.com/index.htmAnother option for added width is wheel spacers, a number of vendors offer them from one inch to three inches. Just to name a few.
Marlin Crawler --------
http://www.marlincrawler.com/Sky Mfg. ----------------
http://www.sky-manufacturing.com/All-Pro -------------------
http://www.allprooffroad.com/Trail Gear ---------------
http://www.trail-gear.com/I would really think about a big lift, the higher you go the less stable it is.
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