Always learning, and having learned that the 5.3 is not the same old dog that it used to be; what with the 243 heads and TBSS intake manifold, I have a question. What year did they start putting this new bird in trucsk? I'd guess 2007 but I could be wrong so I'm asking the local brain trusts............

 

in 2005 GM produced the L33. I haven't stayed up on the newer Gen IV engine designations.

 

The current vortec 5.3s are the 4th generation of LS based engines, which started being put into trucks in 2005...I also think the 243 heads were put in some truck engines in '05 as well, but I think the current TBSS-style intake was only introduced in 07 for the new GMT900...so I think the TBSS intake/243 head combo is only 07+

 

Cool- thanks guys. So how would I know what I'm looking atsay under the hood of a 2007? Something says in the glovebox..............

 

RPO code for the engine is in the glovebox, among the many other RPOs. I think the engine code is near the bottom left, but I could be wrong.

Engine codes for Gen IV are:

RPO Name Displacement
LY2 4800 4,807 cc (4.807 L; 293.3 cu in)
LH6 5300 5,328 cc (5.328 L; 325.1 cu in)
LY5 5300 5,328 cc (5.328 L; 325.1 cu in)
LMG 5300 5,328 cc (5.328 L; 325.1 cu in)
LC9 5300 5,328 cc (5.328 L; 325.1 cu in)
LH8 5300 5,328 cc (5.328 L; 325.1 cu in)
L76 6000 5,967 cc (5.967 L; 364.1 cu in)
LY6 6000 5,967 cc (5.967 L; 364.1 cu in)
LFA 6000 5,967 cc (5.967 L; 364.1 cu in)
L92 6200 6,162 cc (6.162 L; 376.0 cu in)

 

Cool- thanks, Preston...................

 

Sorry, this just bugs me. They are the 4th gen small block not 4th gen LS1. Yeah I'm OCD like that.

Carry on.

 

the only trucks that gonna come with the 5.3/90mm intake is the GMT 900 not the 2007 classic. so dont even worry with looking under the older body style for a gen IV block bc its not gonna be there.

are you getting a new truck?

also you can forget about the
L76/LY6/L92 those heads arent the 243/799s they are the L92 rectangle port heads.

 

Yeah- I'm kinda eye- ballin' what's out there. Fawk! now the 5.3 comes with a 90mm TB? Whoa that rocks.....................

 

No, all truck TBs are 87mm. It's the intake manifold that has the 90mm plenum opening. Easy to get confused, I know I was for a while.

A lot of guys here (myself included) have bought 90mm TBs from cars (corvettes, camaros, G8s) because they bolt up just fine to our truck manifolds.