Bought a motor today and now I'm finding conflicting info on whether it's a 5.3 or 4.8. The link that's scaring me is
http://service.gm.com/dealerworld/vi.../vincard07.pdf
They list the 8th letter as a c is a 5.3 in a car and a 4.8 in a truck. I am not exactly sure what it's out of. I called a dealer and gave them all 9 digits on the back of the block and they said 2007 5.3 Yukon. Can someone help me sleep tonight. Code is C7R217785
also it has 799 heads and is DBW
it has flat top pistons but i read that all 2007 and later motors do.

 

Well, the 799 heads are the same thing as the 243's as far as I know. The rest I', not sure.

 

I'm hoping someone can chime in. I don't want to have to drop the pan if I don't have to. There isn't even any carbon at all on the pistons. It seriously looks brand new inside.

 

Is this the same engine they tried to represent as an Escalade LQ9?
If it was from a car it would have a transverse bell housing and aluminum block.
If it has a strandard bell housing pattern and a truck intake, I see an 07 8th digit c as a truck 4.8.

 

No they had sold the 6liter already. I saw this one sitting on the top rack of the 3 story shelf and climbed up to check it out. It is really really clean. I woulda waited for another day and a 6.0 but they want top dollar for them out here. The block says 4.8 and 5.3. I just recalculated the last nine numbers of the vin that are on the block. yes.... last 9 numbers, that would put the "C" as the check digit, not the engine code. So my vin would be 00000000C7R217785.

 

8th digit O= 5.3 LMG

 

Gary I put in zeros cuz all I have from the Vin is the last 9 stamped on the block.

 

Just a heads up. If you're getting the MSD or Edelbrock spark controller, get the correct one for an 07. I think those are 58x reluctors.

 

I'm gonna look at the plug today.

 

Dropped the pan and found infact it is a 5.3. Through all that excitement I forgot to lookat the reluctor wheel.

 

Pull the crank sensor behind the starter out and look. Easier than dropping the pan again. If you trust it, just look at the sensor body color. Gray = 58x, black = 24x

 

 

The good news is that I only put 4 bolts back in because I wasn't sure if I could reuse the pan gasket

 

You can reuse the oil pan gasket. Just use a little RTV at the 4 corners wher the block joints are.

 

I look at picture post#3>>>Motor is 5.3L