Gathering some intell

[TollKeeper]

So my envoy is still running great. But I cant ignore the fact the engine has some miles on it..

So I am gathering info on my engine and possible replacement, when that time comes, if it ever comes.

I started here... LS Engine Compatibility

I have a 2004 GMC Envoy with the LM4 VIN P 24x V8. These engines are a direct swap for years 2003-2005. Aluminum block.

I know the 2007 and up LH6 will not work as the reluctor was changed from a 24x to 58x.
I know the 2007 and up LS2 will not work for the same reason.

My first question revolves around the 2005-2006 LH6 and LS2. Both are the 24x, and these engines will have the DOD/AFM. Since my current engine wiring harness doesnt have this option, this should not matter. Am I correct in my thinking that all I would need to do to use the 2005-06 LH6/LS2 engines is swap the intake and fuel injectors over? Or are there other challenges I need to be aware of.

I would much rather go the route of the LSA/LS3/LS7/LS9, but that would be a headache adding in the 58x wiring, ecm, and likely having to deal with the AFM/DOD, reprogramming for other things, adding a TCM, etc.

When this does happen (if it happens), the usual stuff will be happening while this goes on, upgrading the diffs from GU6, to GT5. Replacing motor mounts, or other odds and ends.

This is just me gathering info for a "what if" situation. This is not something thats going to happen any time soon.

 

[mrrsm]

Your intelligent and analytical approach to searching and confirming what you want to do is the Hallmark of a Thoughtful, Capable Mechanic. These links may not be precisely what you are seeking... but they both have many hyperlinks at the bottom that will guide you to more specific information:

https://www.onallcylinders.com/2017/09/21/ls-engine-spotters-guide-cars-trucks-ls-engines/

https://www.onallcylinders.com/2017/09/28/ls-engine-spotters-guide-part-2-matching-engine-vehicle/

 

[TollKeeper]

I appreciate that @MRRSM , have those bookmarked for future reference.

 

[Mooseman]

The LS2 6.0L does not have DOD. Easy to tune out though. You would need to beef up the tranny and diff with that engine.

Best thing would be to just rebuild your existing block unless it's grenaded. Then you can choose your cam and get it tuned.

It you do need a replacement block, you can swap in an iron block of the same vintage with 24x, even a 6.0L. Those would be easier to find than an aluminum block. Difference is supposedly just 60-100lbs.

 

[littleblazer]

LQ4/LQ9 swap and done.

 

[Reprise]

^^^ +1 on the 3rd-gen 6.0, however you want to go about it. Yeah, it's iron block, but you'll never have to worry about the bottom end, and you can go any direction you want, if you're thinking about future mods -- either 'all motor', or FI.

If you're going to do a swap, and want a 24x motor, I'd go this route in a second.

 

[mrrsm]

And even with the Added Weight of a reliable and sturdy Cast Iron Block... You can still move to balance the scales somewhat if you ditch the Heavy Cast Iron Stock Exhaust Manifolds for some Lighter Weight, Stainless Steel Shorty Headers.

Weight Loss... Better Performance ...and Some *Bling* ...all at the same time. :>)

 

[TollKeeper]

I'm not really worried about the tranny. When the clutches started slipping some years ago, and it was still under a warranty, I had the GM dealer put a new tranny in. Extended warranty paid for the regular tranny, and I paid the difference for the GM performance tranny.

The front diff I have waiting to go in is from a TBSS, and the rear diff is coming from a 97x Aero, I think. I'm still not sure I went the right course here, I like the G80, never had a LSD. I'm thinking of returning it and just getting a GT5/G80 from whichever vehicle it comes from. I do more where I would need the G80 up in the mountains with snow and off road with the quads.

You are correct that I could just send it out to a machine shop and get it rebuilt, or put a low mileage one in. I have sourced a low milage one, it's out of an 06 97x 5.3. However, that engine likely will not be available when/if this engine goes. And I don't currently have a place to store an engine I might not need. That engine is what got me to start this thread.

At one point I was considering all those performance mods, supercharger, cam, etc. And I definitely have a need for speed. But kids, and old age have shown there ugly head to me, and at this point I just want an absolute bullet proof truck, like it has been for the last 12 years, and 100k miles. So for me, if I do rebuild the engine, I would likely just build it to OE spec, or something very close.

I love my XUV. It literally is there best truck I have ever owned. Truck when I need it to be, grocery getter when I don't. Besides one stress crack in the drivers door that has a bit of rust starting, the truck is completely rust free. I know all the little quirks of this truck and how to manipulate the truck into doing what I ask of it. I would rather have a SWB V8 model, but it's hard to part with something I know so well, for something I know nothing about.

 

[mrrsm]

Mr. TK ...If you decide to experiment in any way with mixing and matching Gear-Axle Ratios and the Drive Geometry for the purposes of better handling the difficult terrain around you, this Link has much to recommend it for breaking down all of the RPO Codes and their respective Gear/Axle Ratio Numbers. The data here probably deserves to added to the appropriate FAQ for this topic as well:

GM RPO Axle Code List | GM Axle Gear Ratio Lookup

Crawlpedia is an off-road encyclopedia featuring a complete list of GM RPO axle codes to find your gear ratio.

www.crawlpedia.com

 

[HARDTRAILZ]

The g86 may actually be a better option than g80 for towing in the snow.

 

[TollKeeper]

The g86 may actually be a better option than g80 for towing in the snow.

Can you give me any more details on that?

 

[HARDTRAILZ]

The g80 locker with unlock at high speed wheel spin. Also once locked you lose side to side traction the g86 will maintain by more easily shifting power and keeping you going straight vs sliding sideways.