My '08 w/ the 6.2 could use some help when towing at higher elevations. Before someone suggests a duramax, I've already considered it. I just fixed my oil leaks and I'd like to consider adding a magnacharger that puts out 6psi of boost. I'm getting mixed messages though about the longevity of these engines. Some are telling me at 120k the engine is just about done and adding a supercharger will kill it. Obviously I don't want to do something that leaves my family an I stranded b/c I killed the engine. So I thought I'd through it out to the forum. What do we think? Do we think the 6.2 at 120k will handle 6psi or is it on it's last leg and this be the a nail in the coffin? Again, this is just to make towing a bit easier, I'm not looking to improve 1/4 mile times. This is my first GM car so coming from a landcruiser and diesel excursion, 120k seems still pretty young to me. Oh and we're only towing about 6k lbs.

 

One thing I am noticing on these motors is they develop quite a bit of combustion chamber carbon build up, and would seek out to complete cleaning that before increasing the compression even more.
For towing improvements I would do gears first our 4.10’s are pretty inadequate even for stock vehicle without towing. 4:88’s would be my choice. And have done it on a Ram truck I had awhile back.

 

Should have mentioned that I already re-geared to 4:56, definitely helped. It's funny you mention carbon build up. I have a friend that owns a service shop and he said the same thing about carbon build up. He suggested using techron periodically. He's was also one of the people that said adding the SC at 120k is not a good idea.

 

At 120k an LS engine is just fine to add forced induction. These engines are good for 250k plus as long as they are taken care of and maintained. Even then they can generally just be rebuilt and good for another 250k. I would go with an Eaton based one (Magnuson) as that will be more bottom end power and should net you 75+ hp.

 

^agreed, they are basically an iron block LS so I wouldn't worry about it

 

Really, the 6.2 in my '08 H2 is an iron block?

 

I just checked my 8th digit in the vin is '8': According to wikipedia this is an L92, Aluminum block and heads.

 

the older LQ4 has the iron block

 

So do we still think the aluminum block is still a 250k motor? Maybe shifting the investment towards a re-manufactured engine makes more sense if the aluminum block is on it's last leg.

 

I installed a SC on a Tacoma 3.4 Aluminum block at 115k never had an issue and it was one of the most fun and power gain improvement modification i have done. With that said i would do it after cleaning the combustion chambers either via head removal or through the spark plug hole with the cylinder at compression stroke. Then a compression test and cylinder balance test to see the top end condition.