al2ride

I have a bit of clunking going on while shifting. I'm going to replace the u-joints in the rear shaft, and at the same time change the oil in the diff. I would like to go with a lubelocker instead of RTV. What axle do I have, Dana 30? It's a totally stock 98 Sport with 4X4 and manual 5 spd. What if there is a lot of play on the diff? I can tear anything appart and fix it, but when it comes to gears I'm totally clueless. Only 80k miles on it.

I got rid of the rough "getting into gear" in the gearbox by replacing the oil with penn synchromesh...now it shifts like butter and no noises. It appears the previous owner used the wrong oil...probably gl5.