As the title states, I bought an 06 GMC Sierra Z71 Ext Cab.. Didn't know it but the truck came with an L33 in it. Truck has 189K miles on it sadly and it is beginning to consume a bit of oil.. Nothing to write the prez about but none the less. I am here to ask what sort of plan everyone would go with on a rebuild.. I know these engines have up near 10:1 compression and great heads.. I was thinking about a set of forged pistons in the neighborhood of 10.5:1, leave the heads alone. Do a mild cam maybe a tr220 or something just to notice it has a cam, and a set of stainless headers and real duals..

How does that sound..

Would anyone suggest anything different?????

Keeping in mind that in stock trim this truck gets nearly 20mpg on the highway and i would like to keep it that way.. So no big stalls no stupid gears.. just a hint of lump at idle, a slight bump in compression and a tune...

Thanks

 

Sounds like a little TLC is in order. Maybe CAI, and some preventative maintenance. Radiator flush, trans flush, diff flush, plugs n wires, and a tune.

Since the winter is coming, check the brakes, rotors, and rotate the tires.

I'd leave the cam and pretty pipes till after the winter, and keep them pretty from the snow, ice, and salt.

 

There is a good chance you can just give it a light hone and rings. I have done quite a few of them for the dealership. If you go forged I would consider checking into boring it to 5.7L. I'm not 100% sure about the 05 but the last 07, and 08 I did had super thick sleeves.

 

If its been taken care of it ought to be fine. You might try a set of valve stem seals first before tearing it down. If you can bore it out to 3.902 that would be the way to go so you can have a 5.7. I'd send the heads off to Richard at WCCH to go through them since they've got some miles on them. Get a circle d 2600 converter that will help a lot and maybe mid 216ish cam. On a stock converter in that heavy truck especially if its a 5.3 is going to suck down low with a 220 cam.

 

I'd go this route, depending on how much the head work would be. If it's more than 2-300 hundred bucks, you could get fully assembled, steel valved 243's for about 650 per pair. Since they are the same design, you wouldn't lose any compression, and that would cover valve guides, seals, and they come with the GM yellow springs, which would be plenty for a decent size "truck" cam. I think I would also add 4.10 gears to your mix. I have an L33 and have found the 3.42's with 33 inch mud tires are just a little on the high side. It is great on the highway, but shifts a lot on hills, and could use a little more gear coming out of the hole.

 

Used to live in SO ILL.

Where you from?

Been tossing around the idea of throwing a small cam in a 6.0 and just swapping that in there.. Right now i like the economy of the 5.3 but at the same time i may very well start using this truck as a weekend offroad play toy..

6.0 torque be mighty nice..

 

I'm in Benton.

 

I was born and raised in Carrier Mills, went to school in C'dale and now working in Columbus Indiana as a Cummins Engineer..

 

Gen III engines use a little oil. It shouldnt need a rebuild if it has been taken care of.

 

Mine consumes consuming oil aswell switched it over to 10-30 and been running good.. also an)l33 with 90k miles.. I get 18-19 fwy miles with 4.10s 30' tires 3600 stall and 222/226 cam.. I use to get 20-22 when I was stock