Is there away to figure out what year is my lq4 block? Also what's the difference between both power wise.. If I'm not mistaken there's a newer version wich is 04 and up, and the older version wich I believe is 02 and down.. Any tips or input will be greatly apriciated

 

The actual blocks itself are the same LQ9/LQ4.

 

The '04 and up thing is referring to the connecting rods used. The LQ9 style rods are stronger and were used in both LQ4 and LQ9 versions starting in '04. The blocks themselves weren't any different.

 

It sort of is important to know the year of the block you’re looking for or already have when building from a bare block. While yes, all the Gen III 6.0L’s are essentially the same and the same part number was used for any given year model LQ4 & LQ9 assembly, there are some important differences that need to be addressed. There was a design change in 12/2003, where as most people are aware that the head bolt lengths were changed to all short pieces, but the cam bearing bores in the block also changed and as such will require the appropriate bearings for the year model block chosen. Only the O.D. of the bearings changed, not the I.D. and is why all the camshafts still interchange.

 

The 6.0 older then 2003 had a different crank that will require the use of a custom built converter to bolt up to a 4l60e. The easiest way to tell if you have the new crank or the old is to look at the back of the engine. The new style will be flush with the back of the engine the old will protrude about 1/2".

 

Only the ’99 & ’00 model 6.0L's with the iron heads had the long crank, the ’01 and up models with aluminum heads came equipped with the common short crank.

 

This is correct. Any aluminum headed 6.0 mated to a 4l80e will have a spacer attached to the end of the crank for proper spacing.

 

Yeah sorry brain fart

 

None. Those didn't start until 01+ although I'm sure there might be some late production 00 6.0s with aluminum heads.