Ok here we go. My current setup:2009 ECSB,5.3,4L60,Volant CAI,RC level,with Cooper Zeon LTZ 275-60-20 and 3.42 W/G80.I have tuned the afm-dod out with a Super Chip tuner.The shifts have been tighten up (stock + 12%) and the speedo adjusted for the taller tires.The truck runs pretty good.The truck also has a Gibson S/S cat-back.Now the fun begins.With the 33" tires I'm thinking maybe 4.30 gears or 4.11.I'm also thinking about installing the Yank ST3200 converter.I'd sure like to here what you fellows think about 4.30 verse 4.11 and 33" tires and the converter.Thanks for your time and replies.

 

niceeeee....does that CAI make the whistle noise???

 

Is it 6 speed????

Edit: Just looked over the 4L60E

Go with 4.10 or 4.11 ... 4.30 is too much gear IMO for a 33" tire

35" tires would call for 4.56 gears.

 

Nice Clean Truck! Have you thought about de-badging it? IMO go with the 4.11's. Big difference between 3.42 and 4.11. I see you are also planning on a stall converter. Future plans include a cam swap?

 

GMCSIERRA5.3, Thanks,no whistle but you can hear it pulling air...

 

Suddog,Thanks for your reply. might go with a maggie in the future..

 

Is that serious? This is a performance website. I would go with AT LEAST 4.30s and my first choice would be 4.56 and I might even consider 4.88s.

33" tires and 4.56 gears is equivalent to running a 28" tire and 3.90 gears.

Let's put it this way. Camaro guys run 4.10s all the time with 26-28" tall tires. That would be like running 5.13 gears with your 33s.

Go with 4.56s. I'm fixing to install some in my truck and I run a 29" tall tire, and I daily drive my truck and drive it on 800 mile round trips at least once or twice a month

 

for being an 09 5.3 it should have the 6L80e not a 4L60e. i thought only the 4.3/4.8 trucks came with the 60e still.

 

It's a 4-speed auto.The crew cabs in 09 had 6-speeds...

 

I would go with 4.10s and the 3200 converter. That should wake it up tremendously. Also I suggest measuring the true rolling circumference of those tires and adjusting the tune accordingly. I guarantee they don't measure a true 33", probably closer to 31.5".