hey im a newbi with trucks and i have a question about my truck i have an 05 silverado and i wanna know if anyone knows what gears do i have and if i should put 4.10s if they dont come with them. and maybe go posi can u guys let me know what i should do for a little more power to.. its a 4.8

 

Welcome to PT.net
You probably are riding on 3.42's. There's a code in the glove box, I forget what the code is but someone will chime in shortly.
4.10's and a good LSD would be a great mod. A lot of us started with gear/posi mods.

Use the search function above and you will find tons of information about what you seek.

 

GT4=3.73
GU6=3.42
GT5=4.10. its in the bottom of your glove box little sticker with a ton of 3 digit codes. oh and g80 is the code for a locker just to make sure you don't have one.

 

my 4.8 came with 3.23...what the code for that?

 

hmmm.... not sure i did a quick search and found those.

 

Most Trucks Not All Most Trucks In 05 Came With 3.23s I Think The Z71 And Some With The Towing Package Came With 3.42

 

Yeah, you most likely have the 3.23 gear. Here's the codes.

GU5: 3.23
GU6: 3.42
GT4: 3.73
GT5: 4.10

 

Are you 2wd or 4wd?