I know this isn't a 500hp+ LSx, but it does get driven hard more often than not.

My daily driver is a 98 S10 ZR2. 4.3l, 4l60e, 8.5" rear with 3.73 gears, and 32" BFG km2's. Recently, I started noticing some odd shifting and torque converter not wanting to stay locked in. Knowing I have a front seal leak and getting ready to fix that in about a month, I've decided to refresh the trans while I'm at it. I also am interested in 'beefing' the trans a little. But would like to know what I can/should do to make it a little more stout and reliable. I do tow about 3000lbs-4000lbs or more on occasion, I do 'hammer' on it from time to time, and I do use it off-Road from time to time. If I know correctly, a shift kit will keep it from slipping as much and keep heat down. But will this make it harsh to drive everyday???? Am i right?? And another question is, will I need to have my ecm tuned to keep the trans working properly with the mods to the trans you recommended??

Thanx for the patience guys. Just looking for some personal preference from people who know how