Hey everyone:

I'm new to the site, found it while searching for info on my 5.3L LC9 oil burner. I have a 2009 Suburban LT that is fairly new to us (2nd owners) but beyond the warranty limits for our used purchase. The suburban has 106k miles on it, mostly highway it seems as the truck is in perfect condition topside and underneath.

It has the AFM which i assume is why it burned up all of the oil in about 2000 miles, at least enough of it to cause some serious knocking. No oil light came on by the way. Long story short, changed the oil before weekend road trip, wife drove it to work next 3 days after. Blew smoke upon starting one afternoon, checked oil and nothing showing on dipstick. Filled oil, started and ran but ticking pretty good ( not in the topend by the way). Drove 1/2 way home oil pressure dropping steadily from 40 to 20. Knocking got progressively worse. Stopped and trailered home.

Quick google search of 5.3L oil consumption and i was shocked! Couldnt even begin to read all of the results. How did i miss that when researching suburbans!!!

Anyway after countless hours of reading on this site and others, i've decided that i do not want to replace the 5.3L with a 5.3L, but i'd like to do a 6.0L swap. I had that same engine in my previous 2500hd and had great success with it.

The 5.3L is out of the suburban on a stand, and the wife is driving one of our other projects. Not in a rush to get it back on road, would like to invest the time in getting it fixed correctly. We love the truck itself and i dont mind doing what it takes to make it right.

I would appreciate any assistance from you guys and gals out there that are more familiar with these engines than i am. I have a nicely equipped garage and the truck is on a lift and i've pulled the engine already. I would me more than happy to provide a detailed step by step writeup on this site with pictures when finished, i noticed there are alot of others asking about this swap as well.

My current plan is to locate a 2009 6.0L from a 2500HD, and get computer also? Is there a recommendation on alum vs iron? or another year/model that is more ideal for the swap? I have the 6 speed transmission with tow/haul in the suburban, is this adequate?

I'll be looking to purchase (assuming i find a good one) in the next week. I'll get some pics to add this evening of the current teardown.

Thanks in advance for your time and recommendations

Barnes

 

the 2009 6.0 from the 2500 will be a good one.. i dont believe it has the AFM crap so thats a plus.
All you really have to do is drop the 6.0 in and get the ECM tuned (from one of our sponsors - Black bear performance, Wheatley, Nelson, mind went blank.....)for it. And your ready to rock and roll!

 

Excellent, thanks for reassurance on the engine choice. i'm currently searching for a good low mileage assembly.

 

My brother had a 2004 LQ4 that just turned over 450,000 miles, untouched besides water pump. They are reliable if they are half way taken care of.

 

even better. in regards to the lq4...that is cast iron correct? will i need to change anything suspension wise on the suburban if i go that route? i believe i read that they are about 100 lbs heavier.

 

What RPM range would you most likely be running this thing in? Figuring it as a daily heavy Suburban, I'd bet that you're looking for max torque at low RPM correct? I may be wrong on my recommendation that follows, but from what I have seen on here it might be the best way to go for you.

Find a low mile LY6 or an (L76 or 07+ LS2 if you'd like to run an aluminum block) (like you were thinking) but make it a short block (either buy it that way or make it that way - sell heads / intake manifold to recoup some costs). The rectangular heads (heads that come on the LY6, L76, L99, L92, and LS3) haven't been as popular with the 2500HD gas guys, as it seems they lack torque down low compared to what a late model 05+ LQ4/9 can produce. Blame it on the LARGE intake ports, large intake valve, blah blah blah. In a car application they're GREAT it seems.

Now, for heads, find a nice set of 243/799 heads (smaller chamber than the 317's for higher static compression which should put you in the low to mid 10.X:1 range. Have them cleaned up with a nice multi-angle valve job and some seat to bowl blending to match up/smooth the port transitions out. LS6/LS3 springs would work just fine, provided you stick with the stock cam or better yet, get a baby cam that maintains intake valve closing event a few degrees near stock (so you don't loose dynamic compression that affects low RPM torque output). By baby, I mean small! Something 206 'ish duration on the intake, and 208/210 'ish on the exhaust, provided you're not looking for rev range to far beyond the stock 6.0 torque curve.

Use the stock intake manifold / throttle body AFTER you have thoroughly cleaned it of any debris.

Should wind up with a nice torquey 6.0 for your Sub.

 

ForcedTQ:

Yes, you are correct in that this will be a daily driver and used regularly for trips back home to NC from PA. When i drove it with the 5.3 i did miss the "torquey" feel of my previous 2500HD with 6.0 on the hilly commute to work.

Your recommendation sounds great, but i gotta admit i'm not as educated on heads and cams. The numbers make my head spin a bit. While i'd love to have the setup you speak of, i'd need some handholding to make it happen.

I'm thinking i may want to stay as "stock/simple" as possible at least until its no longer the wife's daily.


Barnes

 

Would there be any difference in a 6.0 that comes out of a van as opposed to 2500 truck?

 

No.

But let me know where you source your donor engine from as I'm looking for an LQ9 for my yukon. I live just south of you in Cecil County, MD.

 

forced actually has some good ideas, and basically the same thinking that I want todo with my truck. Let me try and save you some cash.
Source a low mileage LY6 out of a 2500hd.
Sell the intake and heads, including rockers as they're unique to the L92 heads.
Use your complete topend off the suburban LC9 (heads, intake, and valvetrain)
I personally would have a valve job done to the heads while they're off, and a set of hardened pushrods since they're cheap.
Junk the 5.3 block, make a table, or scrap it lol.
Now you have a torquey 6.0 with a fresh top-end that will last.

This is the my exact plan for my sierra, except I will probably add a cam to mine. Good Luck!!