Having had both (a later 4Runner and a '94 XJ 4.0 4x4 Sport), I'd say take a close look at both.
Specs have them at about the same length (4Runner slightly longer), XJ is wider, and the 4Runner is taller by < 2 in. Specs on the vehicles are pretty similar, actually.
Here are links, in case you want to review for yourself:
https://www.ultimatespecs.com/car-specs/Jeep/5552/Jeep-Cherokee-(XJ)-40i-Auto.html
https://www.cargurus.com/Cars/1986-Toyota-4Runner-Specs-c4142
Everything you ever wanted to know about the XJ:
http://www.cherokeetalk.com/forum/f64/xj-specs-everything-you-need-know-5719/
Some things to consider:
4Runner is body on frame.
XJ is unibody.
4.0L I-6 Jeep engine is legendary.
Early 4Runner is underpowered - many people do engine swaps. See youtube to watch videos all day long of V8 swaps, etc.
Both cars of this vintage - look for rust.
Look for unibody stress cracks/frame damage on the XJ. Look at the frame and body of the 4Runner for rust and damage/hard use.
Both can be lifted and turned into incredible overlanders.
I found both vehicles to be small on the interior. The Jeep had a low roof, and we were always hitting our heads getting in. Granted, we're 6'2 and 5'11 respectively (me and my wife). This may be less of an issue once lifted.
The 4Runner (my '02) looked bigger - but I found the interior to be very cramped and small. The power roll down rear window was very cool, however. But we seemed to always be rubbing shoulders and fighting for the center armrest. I always 'felt' the 4Runner should have more room inside - it's an optical illusion.
Both are very capable. Jeep XJ's are incredible - they've gone places stock that no Jeep should be able to go. :-)
I see all the time where people have problems packing and getting items out of a 2 door vehicle. It's a pain to have to crawl in to get items that are pushed back. I assume the XJ you're looking at is a 4 door - if so, the XJ gets a slight advantage here, as 4 doors makes it easier to get items in/out, where the 4Runner of this vintage is only 2 door.
I sold my 4Runner, and while it was a nice car, I didn't bond/click with it. I don't really miss it. Now, the new V8 lockable ones... hmm. They're MUCH bigger, however. And way more $$.
We both miss our XJ. In fact, I'm on my 6th Jeep, having owned 2 Cherokees (the XJ and a '11 WK2 Grand Cherokee Hemi 4x4). The rest were wranglers. I have a '16 JKU on my driveway now, which I feel is an amazing overland vehicle platform. I seem to bleed Jeep blood. :-)
Either way, with these vintage vehicles, you'll be putting money in over time to get it where you want, so look at both, and follow your heart!
Let us know what you end up with!
I'm actually considering adding an old XJ to the fleet, to have and play with. They make incredibly capable offroad toys.
Chip
