BB Tune, Range Tech and Oil Consumption 07 5.3L

Farmingdales Finest · October 10, 2014

First off I am not a mechanic so bear with me.

My 2007 Yukon XL last Friday was driving great until suddenly It started making a loud metallic banging noise that got worse with acceleration. I had no warning lights come on. It has had excessive oil consumption since about 40,000 miles and it now has 129,000. Burning about 1qt per thousand miles and my GMC dealer said it was normal and they wouldn't help me when it first did this. I confirmed this with my mechanic that GM considered that normal which we both felt was ridiculous.

On Monday this week I had it towed to my mechanic and he did a motor flush and oil change. That cleared up the noise so he didn't pull open the engine. He said if that didn't work he expected lifter damage. He wants me to drive it for 1,000 miles and bring it back for a change and to check it out to see if there is anything that needs to be addressed. Which leads to my questions.

In my research over last weekend and this week I have read some people say that getting a BB tune or the Range Tech module will get rid of the oil consumption. My question is will they work with a higher mileage engine like mine? Will I need to do anything else to the engine in light of what has recently happened and finally since I am out of warranty which would be a better option for me? I don't beat my truck with high revving , don't tow. I use it as a daily driver to get me to work, home projects on the weekend and to take me hunting and fishing on the weekend.

Thanks in advance!

Snow White · October 10, 2014

most likely you have stuck rings on 1,7,4 or 6 cylinder (deactivating cylinders) which doesn't always mean you can see the smoke from the oil blowby. It's also possible to have a lifter acting up, but if that were the case it would sound like a 7 cylinder with a weird harmonic and be quite a bit down on power with the lifter in a failed collapsed position.

I suspect you now have broken ring and with the broken ring you're getting an absurd amount of piston slap with a sloppy piston floating around in the cylinder. It's like sticking 1/2" bolt in a 3/4" hole if you get my drift...

If that was me, and it was banging, I would have the heads pulled and check out the damage but before you do that.... get a junkyard 2007 engine so you can unbolt the old one and bolt in the new one... they aren't that expensive.

Then, you can get the AFM delete kit, http://www.summitracing.com/parts/cmb-09-0026 <- thats JUST HOW popular the delete is LOL. You can't just slap in new lifters because the cam has a special grind for cylinders 1,7,4 & 6 with different lobe parameters than the 2,3,5, & 8.... so you'll want a cam as well.

IF you do all of that, THEN get the tune done, you're tahoe will be good to go for another 200,000 miles easy.