the stock ones are pretty weak- I've seen threads over at a great big xj site that explains different options for them- one guy used an alt. from a durango or something.
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My Fleet 1996 XJ "Snowball"- 3.5" lift, bunch of little mods. I hate pegleg rear axles! 1974 AMC Javelin "Jade Grenade"- 360v8, 4sp, green inside and out. Underfunded Project. 2009 Kawsaki Vulan 900 "Rocket III"- Summer DD