Re: 235/85R16 tyres on standard LR 5.5J rims?
My opinion, they're probably OK .. but ...
They probably won't look right, a tad like balloons, and I wouldn't do too much off-roading with them as they'll possibly roll over the rims .. In North Yorks a friend had at least two, possibly more, large tyres roll off his rims on a Disco, though different sizes. I think they were something like 33" x 12.5's on 8" rims, so not that far off in relative terms to what you want to do. However, we were off-roading in fairly extreme circumstances!