I have a 96 2500 4x4. I recently moved from fairbanks alaska where my truck has been all of its life to the middle of South Carolina. In alaska the highest octane gas you can get is 89. I usually ran 85 and it ran great. Now that I am in SC I can get 92 but the I use the low stuff which is 87. My truck has been starting to have a ticking noise. I have replaced my spark plug wires and regapped my plugs. But the ticking is still there. Also there are alot of hills here and my over drive kicks in at about 50 mph but my rpm is only at 1100 which causes me to have to downshift to make it up the hills without pissing off everyone behind me because my truck slows down so much. I have 33 in tires with the stock 3.55 gears. Would a gear change help this? I hate having to drive my truck at almost 3000 rpm all the time to get up the hills. Any help would be welcomed.

 

changing gears would help the constant shifting on hills, but i have 4:10 gears and mine will still kick out of o/d while climbing hills at 50. If it bothers you, you can just keep it out of o/d on back roads. i run at about 2000-2500 rpm's up hills. as far as the ticking, you could try different plugs. search for plugs and there are a lot of topics on temp ranges on plugs.