Will the computer accept the 4.10s instead of the 3.42? Will i be governed down to 70mph? It all makes sense bc of the trans. speed, but i dont know. Someone please fill me in!

 

IMO from my experience, yes. I had mine regeared from 3.73 to 4.56. The speedo was way off, the shifts were way early and I tripped an ABS light. I didn't drive it long enough to test the speed limiter, only about a mile. I already had a Predator so it was easy to tune out.

I stopped about a mile down the road and programmed in the gear change. That fixed the ABS light but the speedo and shifts were still way off. I played with the tire size several times to get it exact but I finally did. Now I have no problems with the ABS, the speedo is almost perfect, and the shifts are where they should be but the computer thinks I riding on 215/50/17's . (note my actual tire size in my sig)

You will want tuning of some sort.

 

I just went from 3.42's to 4.10's and my speedo is off by about 10mph.. I have run it to about 90 though and everything is fine.. Truck runs so much better. I had a 02 pcm ready to swap out and something was wrong with it, so my next one should be here friday, and hopefully that will correct everything.. The only thing that happened to me was that my ABS and parking brake lights come on..