I'm thinking that the 4.0 would be straining with that heavy of a body.
Let's check the specs... from the book pages I posted above, the 4wd Savari kerb weight is 1770 kg (3902 lbs.) and it's powered by a 4-cylinder diesel generating 59 horsepower and 150 nm of torque (110 ft. lbs.)
The curb weight of a 2006 LJ with a hardtop is is 3850 lbs. and it's powered by a 190 hp inline 6 generating 235 ft.lbs. of torque.
So the LJ is within 50 lbs. of the Savari with over three times the horsepower and twice the torque. No problem there.
Let's also look at my Wrangler pickup. The wheelbase of the Savari is 2900mm (114 inches). The extended wheelbase of my pickup is 123.5", so there's more frame weight of the pickup to consider. The pickup curb weight is 4200 lbs. (the frame extension and bed mostly are the extra lbs.) I've never felt that the pickup is underpowered, and I regularly carry heavy loads in the bed or tow my trailer with enough cargo to push the trailer over 2500 lbs.
I think a Savari with on LJ frame stretched to 114" will be just fine, both on the trail and on the highway.
Even with it's small diesel, the Savari does very well in rural taxi service in the foothills of the Himalayas, it's not uncommon to load 20 people in/on one in taxi service.
And they do pretty well on the trails too, even with the not-uncommon bald tires in rural use in India, check this one out:
I think a 4.0 powered Savari on an LJ frame would be the perfect overlander. My wife continually encourages me to import one and convert it. Maybe Dan and I should each import one and save on the container costs
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