Potential Re-Gear idea

[fozzi58]

Not exactly relevant to OP's situation, but relevant to the conversation overall....

I went from 3.08's with the 6L80 to 4.10s. I did that mainly for racing.

On my daily tires which are 305/35 24s, RPMs are about 2250 at 75mph.
On my race tires which are 265/30 22s, The RPMs are closer to 2700 at 75mph.

I don't daily my race wheels but I have been on them for a few weeks at a time while trying to get my 24's powder coated, straightened, etc.

It was def too big of a jump and I think 3.55s or 3.73s would have been sufficient. I was running consistently above or below 14.1 at the track with the 3.08's. I should most definitely run a sub 14 with the 4.10's, the question is how sub am I going. I am hoping for a .5 second drop in ETs which would put me at mid 13's but that's high hopes.

I wish there was a way to change the final drive gear in the 6L80 cause a taller 6th would really just make the truck an overall pleasure to drive

 

[91RS]

What are you trying to accomplish? The difference won't be "huge," but it will be noticeable. You will likely get off the line a little faster, have a little less passing ability, and get slightly worse fuel economy. It'll probably tow better but I would feel it wouldn't be worth it for that unless you're towing every day. I don't feel it would be worth doing on a stock truck, but it might be if you have modifications in power, wheel/tire size, etc. it might be worth it depending on what exactly your goal is.

It is completely apples to oranges, but I did some gear ratio changes in my SS (which is a manual, weights a lot less than these trucks, and has a lot more power) but people were telling me that I wouldn't even notice going up or down one ratio, which was completely false. I went from the stock 3.70 to a 3.91, which was very aggressive off the line and cost me 2 MPG. Then I went to a 3.45, which was much better for daily driving but not aggressive enough for when I wanted that and now the car lugs a lot more. So, I'm going back to stock.

 

[swathdiver]

Not exactly relevant to OP's situation, but relevant to the conversation overall....

I went from 3.08's with the 6L80 to 4.10s. I did that mainly for racing.

On my daily tires which are 305/35 24s, RPMs are about 2250 at 75mph.
On my race tires which are 265/30 22s, The RPMs are closer to 2700 at 75mph.

I don't daily my race wheels but I have been on them for a few weeks at a time while trying to get my 24's powder coated, straightened, etc.

It was def too big of a jump and I think 3.55s or 3.73s would have been sufficient. I was running consistently above or below 14.1 at the track with the 3.08's. I should most definitely run a sub 14 with the 4.10's, the question is how sub am I going. I am hoping for a .5 second drop in ETs which would put me at mid 13's but that's high hopes.

I wish there was a way to change the final drive gear in the 6L80 cause a taller 6th would really just make the truck an overall pleasure to drive

Post up some timeslips next time out! I'll be taking mine back out as soon as the track opens up again.