2003 LQ4 Cam Housing 1st or 2nd Design

[dag19]

I've got a 2003 LQ4 6 liter. Just so happens 2003 is when there is a 1st Series Design and a 2nd Series Design for the cam housings. How would I go about identifying which design I have? I am trying to order a new cam and bearings but want to make sure I get the right parts.


Cam Housing Bore Diameter
Bore 1/5 = 2.326, Bore 2/4 = 2.317, Bore 3 = 2.307 (1999-2003 1st design)

Bore 1/5 = 2.346, Bore 2/4 = 2.326, Bore 3 = 2.307 (2003- 2007 2nd design)

[AussieinNC]

As far as I know there is no way to identify externally whether the engine of series 1 or series 2.

Simplest way..wait until you pull the cam before you order the parts....

Measure the journal diameters then order the right cam.

[dag19]

I was afraid that was going to be the answer...cheers to the waiting game!! Thank you sir!

[71cadc10]

knock out old cam bearings first, then order the set you need

the cam itself doesn't change...just the cam bearings (you likely know that but just making sure)

[AussieinNC]

Unless the cam bearings in the block are damaged, I would suggest leaving them alone...
Be aware that factory line bores the cam tunnel after the bearings are installed due to core shift issues...or at least what a lot of info suggests...

So if you see a cross hatch on the bearing surfaces it is not a failure point...