How to tell if I have a LQ9 or LQ4 this gets weird
#1
How to tell if I have a LQ9 or LQ4 this gets weird
I know I know, use the search, but I did that. Obviously the LQ9 has flat tops and the LQ4 is dish. However, I cannot see well enough into any of the spark plug holes to tell if the motor is an LQ9 or LQ4. The only thing I can see is that there is a number 0 stamped into the top of the piston as thought it was put there with a dot matrix printer. Now, the motor I'm told came out of a '04 GMC Denali which means it should be an LQ4 I know, but looking at the side of the cylinder head where they stamp the last 10 digits of the VIN in, I see the letter N, which I thought should mean it's an LQ9. Also I took the oil pan off and windage tray to peek inside the block to do a general once over to make sure everything is fine. I then come to find that this motor has Dimpled rods. Do dimpled connecting rods only come on LQ9's? Also, is there a way to identify from the bottom of the piston any casting marks or numbers that could tell me if it was a dish or flattop piston? I don't feel like yanking a head off to look but I need to know the compression of the motor so I can intelligently select a cam.
#2
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I think the only way you are going to know for sure is to pull the heads. From what I have seen if the engine was from an '04 then like you thought it should be an LQ4. If it was from a Denali manufactured in '04 for the 2005 model year however, it could be an LQ9.
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Man, thank GOD you said that Shannon! It should never be tghis difficult for someone to find out. Guys, here's a word of advice to always remember. You engine and transmissions RPO code will always be tagged to your vin. So when in doubt....ask someone to decode your VIN #
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#8
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Man, thank GOD you said that Shannon! It should never be tghis difficult for someone to find out. Guys, here's a word of advice to always remember. You engine and transmissions RPO code will always be tagged to your vin. So when in doubt....ask someone to decode your VIN #
FWIW - My 6.0 said it came from a 2500 Silverado, but the paperwork that showed up with it save vin code N. I pulled the oil pan to look at the rods and was convinced that I had gotten an LQ9. Later when I finally took the motor apart, I found out that I had the dished pistons. The people who sell these motors don't always know what they are talking about.
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How does he have the VIN from the truck it came from? Do they really stamp it on the cylinder head? That's the first I've ever heard of it.
FWIW - My 6.0 said it came from a 2500 Silverado, but the paperwork that showed up with it save vin code N. I pulled the oil pan to look at the rods and was convinced that I had gotten an LQ9. Later when I finally took the motor apart, I found out that I had the dished pistons. The people who sell these motors don't always know what they are talking about.
FWIW - My 6.0 said it came from a 2500 Silverado, but the paperwork that showed up with it save vin code N. I pulled the oil pan to look at the rods and was convinced that I had gotten an LQ9. Later when I finally took the motor apart, I found out that I had the dished pistons. The people who sell these motors don't always know what they are talking about.