transmission issues

i have a 1996 cherokee se. when i got the jeep it had the cluster with the speedo and gas gauge. i took it through the mountain in snow and mud and didn't have any issues with the transmission. a couple days ago i swapped in the cluster with all of the gauges, 3" lift up front, 4" in the rear, 31x10.50 tires and longer shocks. after doing this i took it in the mountain in about the same amount of snow as i have before (about 10"). the jeep was doing good but i started to notice that the jeep seemed to be struggling and started to smell hot and the temp gauge started to go up to the red so i shut it off. i let it sit for a little and put it in 4 low and 1-2 on my automatic shifter and this worked a little better but i still had the same result. this had happened once before i put the bigger tires on. but that time the jeep would miss and stall out if i gave it gas at idle in park. is this a transmission issue or something else? im thinking its the transmission because of the hot smell, but the fluid doesn't look or smell burnt on the stick.