epfatboy

iTrader: (3)

While tearing down my 2002 LQ9 I noticed the rod ends were larger than I expected and sure enough they are GEN4 rods.

This engine came out of a 2002 Escalade. It has a Blue/red PCM and is a 6+2 DBW with a 4L60e.

I was looking specifically for a 04-07 Gen3 LQ9 ‘cause I’m gonna spray it and wanted the gen4 rods. I settled for this low mileage queen (144K on the odo) and she’s treating me right already…

Just for that I think I’ll polish her crank while I’m in here…

G Atsma

WHOA!! Way to go!

epfatboy

iTrader: (3)

Photo evidence

https://photos.app.goo.gl/3CyRyzyiiUSkr9ov5

https://photos.app.goo.gl/7pxaASyCrqwfLpXw5

01FormulaTA

iTrader: (20)

The LQ9 was the first engine to get the newer rods with the floating pins, the first year of the LQ9 was 2002. All LQ9s have them, the 4.8/5.3's started to get them later in 04+

epfatboy

iTrader: (3)

So are the rod and main bearings the same as an LQ4 with GEN3 rods?

I assume the journal sizes are the same, the difference being counter weight balancing only?

01CamaroSSTx

iTrader: (3)

Correct!

epfatboy

iTrader: (3)

You know what is different... cam bearings...

Looks like in 2002 the LQ9 uses the 2nd DESIGN cam bearing, that will teach me to just assume.

NOTE:
I planed on the dura bond CH-10 this is the 1st design. The dura bond second design is CH-23 (larger bore same width) BUT... everyone is out of stock and as I can tell the CH-25 is the 3rd design but is a substitute (same bore as CH-23, .145 wider) for the CH-23. Just repeating what I'm reading, I'll keep you posted.

epfatboy

iTrader: (3)

I should note the head bolts still are the early design and need 4 short bolts.

Che70velle

iTrader: (6)

The CHP-23T is a Teflon coated bearing that is a direct replacement for the out of stock CH-23’s. Of course there expensive.

Fast355

I have a 2006 LQ4 with them too. Also came from GM with the LY6 style pistons.

JacobChevys

That is true ^ all LQ9s have them. I believe they are the exact same as the LS2

epfatboy

iTrader: (3)

Hey thought I'd update, I was 100% WRONG when I thought I might have had 2nd design cam bearings. I dug out the old bearings and measured and they are in fact 1st design as they should be.
I did a little chamfering/deburring on the block bores and hammered a new set in of 1st design no problem. 95% prep, 5% execution.

Che70velle

iTrader: (6)

Good on you sir. Keep us updated on the build please. We like pictures also…

epfatboy

iTrader: (3)

Here is a google photo library of the engine build.

https://photos.app.goo.gl/jSsqDm8FzDab97ds8


it’s going slow but it’s going. I’ll toss a few pics of the car in there too.

JacobChevys

Looks good man keep us updated! I’m doing something very similar.

question did you have the block machined or did you just do a quick cleanup on the bores(cylinder walls) with a dingle berry hone?

epfatboy

iTrader: (3)

Just cleaned up the walls.

I ran a stone hone thru first to check how straight the walls were then ball honed it.

No ridge at all, pistons (new rings, gapped to 22) tapped in real nice.

epfatboy

iTrader: (3)

Just to say this…

I decided to replace the cam bearings and that meant the pistons were coming out. Since the pistons were coming out I was gonna have a look at the mains.

Both the rod and main bearings looked great but I let the magic out and I needed new rod and main bearings

So the only thing that went thru the shop was the crank to get polished.

If you really want to keep your JY build to a minimum don’t look at your cam bearings;-)


next up I’m going thru some 799 heads.