I am curious, whenever i Look in parts catalogues or websites, it seems that parts are for 99-04, 05-06, and 07+

WHat makes the 05 different? Is it because 05 is drive by wire?

 

What kinds of parts are you looking at?

I think drive by wire started in 03 but I'm not sure. in 05 they went to drum brakes in the rear. Fuel filter is in the tank with the pump. The front grille is different and HD hoods went on in 06-07 classic. All I can think of off the top of my head.

 

05+ is efans

Other than that, it really depends on what mods you're talking about. 99.99% of the mods are the same for all 99-07 trucks.

 

+1, although the suburbans with traction control got DBW as early as 01

 

Some trucks too in 01

 

Efans, bigger brakes up front (and subsequently you can't fit a wheel smaller than 17"), drums in the rear...

That's all I can think of right now.

 

My 07' sierra classic is the definition of a bastard. However all parts fit backward from that year.

 

Arent the head styles different? Cathedral vs Rectangular ports?

Thanks for the input guys...

 

All of the GENIII truck engines should be cathedral port. I'm not sure which heads are rectangular port, but I've never seen a GENIII with them.

 

06s and 07s nbs have a crappy OS