Just looked this up last week to see if I could pull our new pop up tent trailer with my '87. I believe it was 2300#. I figure with air bags in the rear and a sway control bar I should be safe with 2800#. It also specified not to use a weight distributing hitch.
One of the most significant issues is brakes. If you have your trailer (or towed car) rigged with a brake, your safe weight is half again to twice what it is without it. I pull a 2100 lb camper/trailer with my fj40 with an F engine. But I wouldn't feel comfortable at half that if it didn't have electric brakes. An FJ40 weighs about 3800 lbs, so it would be a bit more to pull. I imagine your 60 with a 2f is about as capable as my 40. It is a drag, and don't expect to be flying down the interstate at 80 mph. On the other hand, I got where I was going in reasonable time, through 6000 feet of elevation change.
Hmmm...I think my trailer alone goes ~ 1200 lbs. Then add in the 40....I pulled the Ingot from Montgomery AL to Annapolis in a day. Slow to be sure...but patience, perserverance and elec trailer brakes.
You can pull it with the '60. We pulled an FJ55 with our '84 BJ60. It's not fast but it works. Also towed a flat bed trailer with the FJ55 body up from California, slow but doable. I wouldn't recommend making a habit of it though. In otherwords don't think of the FJ60 as a tow vehicle for the FJ40.