Underdrive pulleys on a NNBS silverado

[icetraxx08]

I have done a search and read through them but all I have found is members saying that they have them and are going to install and not a followup.

I have a set of underdrive pulleys sitting on my back seat. I am on the fence on taking them back and using the money for either stereo/speaker upgrade or some nerf bars. I have a 08 crew cab with the 5.3ltr. I have a custom tune, dynatech long tube headers & cats, corsa touring cat-back exhaust, and a cai. To those that have installed them in a 07-up nnbs was it worth the install?
Thanks,
Larry

[icetraxx08]

any one have these on a nnbs?

[oleshifty]

have one on my 01...same motor. PUT THEM ON

[Mang213]

Its a simple upgrade for little money and no real side effects. Go for it and let us know your results

[11 6.2]

Its a simple upgrade for little money and no real side effects. Go for it and let us know your results

+1

[pl4yboy]

have one on my 01...same motor. PUT THEM ON

Not the same motor. His is a Gen4 with VVT.

[Mang213]

Did all 5.3's have vvt in '08?

[cjriojas]

i thought only the 6.2 had vvt

[pl4yboy]

i thought only the 6.2 had vvt

My 5.3 has it.

Did all 5.3's have vvt in '08?

I THINK. I'm not positive.

[GasGuzzler]

You would be surprised how many different engines these things can have....VIN derivitives and RPO's confirm there is more than one of some of the sizes but I'm not sure of all the differences. My dad's GMT900 (NNBS) 2007 Sierra has Flex-Fuel and 4 cylinder mode but no VVT. I too thought the VVT was 6.2 only.