switch a four speed for a six speed

[Vermontah]

i have a 05 2500hd silverado with the 6.0. I love the truck. I bought it with 94000 and now it has 145000. It has been flawless. The tranny just started to like from the front seal. Nothing to bad, maybe a 1/2 quart a month. I'm in a wait and see pattern right now. I dont think its anything to panic over. However if it gets worse and I have to pull the tranny to replace the seal i will think about putting a remaned tranny back in its place. That said I will get to the real question. Is it possible and what would be involved in replacing the four speed with a six speed out of a newer truck. I am thinking the six speed would help with mpg especialy on the highway. thanx for all your input

[RyanbabZ71]

no need for multiple topics in different areas asking the same exact question. Closing this thread. The other already has replies.