2008 L76 6.0L engine swap

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

AlexMahon

TYF Newbie
Joined
Mar 24, 2023
Posts
15
Reaction score
23
Which engines are a 1-to-1 swap for the 2008 L76 6.0L engine? Which transmissions are a 1-to-1 swap for the 2WD 4L70-E? Time to start thinking about a reman or crate engine without AFM/DOD and trans and would like a 6.2L with a beefier trans. If not a 6.2, another 6.0.
 

Marky Dissod

Full Access Member
Joined
Mar 3, 2023
Posts
4,232
Reaction score
6,175
Location
(718)-
So far as external dimensions go, ANY GM Gen3/4 4.8L / 5.3L / 5.7L / 6.0L / 6.2L / 7.0L V8 is physically interchangeable with any other.
That's why they're called GM Small-Block V8s.

If you're not willing to run a custom 87 octane ecm tune for the 6.2L,
you're likely better off with another 6.0L; 6.0L V8s tend to be cheaper to acquire than 6.2L V8s.
If you plan on physically deleting the VVT, seriously consider the 243/799 holy port heads used on the LS2.
If you plan on keeping VVT operational, stick with rectangular port heads.

@NickTransmissions would know how to better answer this question; all I can say is you ought to look for RPO M70.
I do know, however, that any 4L60E M30 / 4L65E M32 can be rebuilt to meet or even exceed M70 specs.
 
OP
OP
A

AlexMahon

TYF Newbie
Joined
Mar 24, 2023
Posts
15
Reaction score
23
Thank you for your response, Marky.

What I'm looking for is total 1-to-1. Not just block fit, but wiring harness, ECM, TCM, etc., e.g., just the lazy man's drop-in. Which of the following non-AFM/DOD 6.0 or 6.2. engines will fit 1-to-1 everything:
"K"/LY6/6.0 2007-10
"G"/LY9/6.0 2010-17
"2"/L9H/6.2 2009-13
"8"/L92/6.2 2007-08
"H"/LS2/6.0 2005-07
"W"/LS3/6.2 2009-17

Re: the trans, I'm satisfied with the 4L70-E, but would like to explore other options, again for an easy 1-to-1 fit. Is the 4L70-E the best of the lot?

In addition to the 1-t0-1 total fit information, which of the "fits" are recommended and why?

My purpose is to find the least expensive/best reman'd or crate engine that will require minimum modification for 1-to-1.

Thank you.
Alex
 

Marky Dissod

Full Access Member
Joined
Mar 3, 2023
Posts
4,232
Reaction score
6,175
Location
(718)-
What I'm looking for is total 1-to-1. Not just block fit, but wiring harness, ECM, TCM, etc., e.g., just the lazy man's drop-in.
Besides an L76?
Which of the following non-AFM/DOD 6.0L or 6.2L engines will fit 1-to-1 everything:
"K"/LY6/6.0L 2007-10
"G"/L96/6.0L 2010-17
("H"/LS2/6.0L 2005-07)

"8"/L92/6.2L 2007-08
"2"/L9H/6.2L 2009-13
("W"/LS3/6.2L 2009-17)
Parenthesized LS2 & LS3, because I actually think those are closest to what you want ...
Are you asking about a CAR engine on an SUV forum? Did I just get psyched out or something?

Having said all that, I consider ANY of the above engines effectively interchangeable with each other,
but that's because I'd be willing to work around the wiring harnesses & ecms & tcms.
I'd also consider the V8s you're not considering that have V4 crap,
because I'd delete all that V4 schidt before installation - it ain't hard with the engine in the open,
and once deleted, an L77 (for example) becomes an L76 with flexfuel capability.
Re: the trans, I'm satisfied with the 4L70E, but would like to explore other options, again for an easy 1-to-1 fit. Is the 4L70E the best of the lot?
In addition to the 1-to-1 total fit information, which of the "fits" are recommended and why?

My purpose is to find the least expensive/best reman'd or crate engine that will require minimum modification for 1-to-1.
You may want to wait for an answer from someone else regarding the transmissions,
but I believe that the 4L70E / M70 only came from TrailBlazers SS, which are all AWD (I'd LOVE to be wrong here!).
 

j91z28d1

Full Access Member
Joined
Feb 28, 2022
Posts
4,657
Reaction score
5,903
to have a 6.0 in a 08. do you have a 2500?

and I thought 6.0 was non afm already.


in general, the 6.0 is considered one of the best/ most reliable truck engines. I'm not sure I'd go thru the hassle for 0.2L more.
 

swathdiver

Full Access Member
Joined
May 18, 2017
Posts
21,321
Reaction score
30,315
Location
Treasure Coast, Florida
Which engines are a 1-to-1 swap for the 2008 L76 6.0L engine? Which transmissions are a 1-to-1 swap for the 2WD 4L70-E? Time to start thinking about a reman or crate engine without AFM/DOD and trans and would like a 6.2L with a beefier trans. If not a 6.2, another 6.0.
The LY6 is about as close as you can get to 1:1 with no other changes. The L92 would work but you're really going to need a tune. The L94 and L9H are Flex Fuel engines with larger injectors and a tune would be required to get it running right unless you used your old injectors and harness, etc.

The 4L70 Supermatic was the ultimate 4-speed. It is not backwards compatible with the older 4L60/65 if memory serves. It's a royal pain to swap over to the 6-speeds but can be done with lots of time and money. Even 10-speed swaps can be done now.
 

swathdiver

Full Access Member
Joined
May 18, 2017
Posts
21,321
Reaction score
30,315
Location
Treasure Coast, Florida
to have a 6.0 in a 08. do you have a 2500?

and I thought 6.0 was non afm already.


in general, the 6.0 is considered one of the best/ most reliable truck engines. I'm not sure I'd go thru the hassle for 0.2L more.
The L76 was an all aluminum hot rod 6.0 with AFM and VVT used from 2007-2009 in the GMT900s.
 
OP
OP
A

AlexMahon

TYF Newbie
Joined
Mar 24, 2023
Posts
15
Reaction score
23
Thank you for all your responses. The present setup is OEM for a 2008 Yukon 1500 SLT 2WD, i.e., the L76 6.0L and the M70/4L70-E. I have installed a Range AFM disable OBD port device that cuts out the AFM. You've collectively answered my question re: the trans - stick with the 4L70-E. Re: the engine, it would be nice to get the additional torque that an LS3 would provide (420 lbs. v. 375 lbs. = +45 lbs./+12%), but not when considering the hassle of mixing and matching ECM and TCM variables. This entire inquiry is in anticipation of a crate or reman (minus the AFM) down the road - I've got about 177K on the odometer and would rather pre-emptively re-engine at about 200K (about a year from now) rather than wait for the current engine to die (the Arizona-only body/frame is perfect with numerous suspension enhancements). Thanks again to you all.
 

Marky Dissod

Full Access Member
Joined
Mar 3, 2023
Posts
4,232
Reaction score
6,175
Location
(718)-
... it would be nice to get the additional torque that an LS3 would provide (420 lbs. v. 375 lbs. = +45 lbs./+12%),
but not when considering the hassle of mixing and matching ECM & TCM variables ...
'Hassle'? About $500 more, to make an LS3 / L92 / L9H work, is a 'hassle'?
Sounds to me like passing up a bang-for-the-buck-upgrade. L92 / L9H would be easier.
... got about 177K on the odo, would rather preemptively re-engine at about 200K (about a year from now) rather than wait for the current engine to die ...
You gonna sell off the old L76 to defray the costs, or keep it and rebuild it?
 

donjetman

Full Access Member
Joined
Oct 22, 2018
Posts
2,005
Reaction score
3,690

MWR Denali

Member
Joined
Sep 19, 2016
Posts
33
Reaction score
28
I swapped the factory L76 in my 2007 Avalanche for an LS3. I also wanted to eliminate AFM/VVT, although if I had to do it over again I'd probably keep the VVT. There were limited VVT cam options at the time when I originally did the swap in 2015. I've got about 60k on the swap now and it's been great. I sold my 125k mile L76 for $1800 and the buyer/friend included a start-up tune for the LS3. I went the LS3 route since I was able to "delete" AFM and VVT without having to pull a head bolt. I added a cam, converter and longtubes as well, but you could skip that if you wanted and the tune would be a breeze. I ended up with a brand new engine, and no AFM to worry about for not much more than what it would cost to address the issues I was having (broken exhaust manifold bolts and a few annoying fluid leaks). I did blow the stock trans on the first drive (and twice more thereafter), but I've since addressed that as well. I'd have RPM build you a 4L70 and send yours as a core and you won't have to worry about it again.

I know you want a 1:1 swap but the LS3 is about as simple as a modern swap gets. I believe I have a word doc with all the parts I used if you have any specific questions. Off the top of my head I did need a 3-bolt cam gear, MAP adapter harness, I had to adapt the knock sensors, I used a Camaro water pump and tensioner, and needed to adapt a few accessories for belt routing. I did a ton of other maintenance while I was at it like motor mounts, etc.
 

Forum statistics

Threads
138,049
Posts
1,997,878
Members
102,990
Latest member
spectol
Back
Top