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Northwest Chapter
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what's the deal with the pcm's? do they interact with the bcm? if not, i don't see why you couldn't swap a 6.0 pcm/harness out of a 2500 onto a SS drivetrain and reprogram the 2500 pcm's tables...
They are a wacky ordeal, GM's bastard child brewed in the depths of he|| solely because GM didnt have a PCM that could run the VVT on the exhaust cam of the I6. You can tell they werent liked because the GMT355 platform with the I4/5 motors got the P12 from the beginning and the I6 got it in 06-07.

If you have a SS drivetrain might as well use the SS wiring. If not you'll run into issues with the reluctor rings being wrong (another reason the P10 cant run anything else, it uses a 7x reluctor whereas the E40 V8s use a 24x and the E67s use a 58x). This can be overcome easily with swapping parts, but that gets expensive (but again you're doing a swap so what isnt expensive).

If you start with a donor I6 truck, Ive been thinking you might be able to swap an LS1 512kb or 1mb PCM in like the 02-04 LWB trucks with the 5.3 used. If you used a 512kb one you would also be able to run Custom Operating Systems from EFILive or HPTuners for nitrous, SD, etc. Downfall, if you want to use a Gen IV motor you have to swap some hard parts (like the crank reluctor, knock sensors, probably more) and maybe change the fuel system (depends on the donor year TB). But if this LS1 PCM swap works, swapping a Gen III small block Chevy in would be easy. Bolt it up, pick the OS you want to use (build your wiring harness around this specific OS, probably an F-body one), full flash the PCM with the appropriate cal and done. Not an SS swap, but a V8 swap and there isnt anything that says you cant use a stroker LS1, blown LQ9 (ala Silverado SS, Escalade), heck even start with the baby 4.8L and bore/stroke it for some serious power.

And yes they interact with the BCM, they affect the cluster too (but that may be through interaction with the BCM).


Yea, I thought they were different Erik. Wasn't sure what the difference was, but figured there were difference, being that the HP and TQ numbers differ so much with the different vehicles. Like I said, not sure about the computers, and how they'll interact with the different components. Thanks for the info Erik! :thumbsup:
The difference between say a 2500 HD 6.0L and the TBSS 6.0L is not simply software. Packaging, cooling system (ours blows compared to the full size), transmission, rear end size/ratio, and then the critical things like iron vs aluminum block, truck intake vs car intake (both have the truck but you can swap them with efans), compression ratio, etc all factor into the power ratings.
 

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2002 chevy trailblazer_ls
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219 Posts
so you couldn't pick up an ls3, ls controller, 4l85e, and tranny controller from gmpp and rig up the gauges to work with the outputs from the controllers? :confused:
 

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Northwest Chapter
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so you couldn't pick up an ls3, ls controller, 4l85e, and tranny controller from gmpp and rig up the gauges to work with the outputs from the controllers? :confused:
Maybe, but you'd lose 4WD (if you have it), have to beef the rear diff up, then you might be able to get the E67 ECM working but its doubtful. Guages and DIC are almost a dead no.

If you start with a V8 base truck, you'd be a lot better off. Even an EXT with a V8, SWB 5.3 would be a TON easier than the I6 simply due to the differences in engine harnesses.
 

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2002 chevy trailblazer_lt
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Just a hint to everybody - you can subscribe silently to a thread by using the Thread Tools pulldown menu. No need to clutter the thread with a post.
^ :crackup: :dielaugh:


I think this is a brilliant idea doing this swap, although i think i'd leave it to where it still looks like a regular TB. If you do that then people might will be like oh it's just another TB then when you race em they'll be like :eek: :eek: :ugh:! :crackup:
 

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2002 chevy trailblazer_ltz
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Any updates? i was thinking of getting a 4.8 or 5.3 from a truck and wiring harness. BTW the SS 6.0l LS2 is Gen IV. A 6.0 from denali,escadale,2500 truck pre 2007 are Gen III
 

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Northwest Chapter
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Any updates? i was thinking of getting a 4.8 or 5.3 from a truck and wiring harness. BTW the SS 6.0l LS2 is Gen IV. A 6.0 from denali,escadale,2500 truck pre 2007 are Gen III
Im curious as well, hope I didnt scare the OP off with my long-winded responses. But everyone who thinks about this should know what they're getting into, its not a simple engine swap by any means.

I really wish we could figure out if the BCM actually cares what PCM is feeding it information...as long as it gets a class 2 serial comm (GM's used the same protocol type since OBDII in '96) it should be able to interpret the signals...

Be prepared to redo a lot of that harness. I think anyone trying to do a Gen III swap should look at rewiring their harness to use a LS1 PCM, not an E40/E67 and T42. Should be easier, can leave the engine 100% stock if you so desire (no reluctor issues, etc). Plus the LS1 PCM is very powerful, especially if you throw a Custom OS at it. I can get the pinouts for the LS1 PCM used in the 03-04 LWB trucks if anyone wants it.
 

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2002 chevy trailblazer_ltz
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I have the 4l60e on my 02 Trail. it should be the same as the one in the trucks, heck im even running a i-6 trailblazer stall on my 03 silverado. By getting a gen III engine with a complete harness its up to figure from the 0bII to the ls1 pcm theres no need to do a Gen IV Pcm/Tcm. After that just worry about the drivetrain axles and motor mounts.


Here is a Wikipedia on LS based Motors

http://en.wikipedia.org/wiki/GM_LS_engine
 

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2006 chevy
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72 Posts
After reading through all these posts still no pics. :bonk: Sack punch for you. You've got my attention on this one. Very difficult to say the least.

I think you'd be better off just putting your body on the SS frame:woot:
 

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2005 chevy trailblazer_ls
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Okay Soooo I have a question...
So if I take a let's say a 5.3 envoy denali motor and harness and put it in my 05 tb why wouldn't the bcm communicate together?

When you purchase a bone yard 5.3 denali engine it comes with the harness and you can add the ecm for 150. So why wouldn't this work?

As for the 4l60 why change it or the t-case out? If the tcm is tuned correctly in gto's i've put over 550 to the tires stock.

I'm planning to do this but you all have me kinda worried. But on paper 5.3 denali's harness should pretty much bolt in. As for the bcm I'm bot sure yet I guess I'll try to get the bcm also. I'm also not sure on the gauge cluster.

I'm kinda stuck on which exhaust to use looking for stock SS exhaust but haven't found one yet.

Why change anything other than the engine I'm sure the transfer case is stronger than everyone thinks.
Has anyone actually tried this or no? If so did they use a stock harness? I'm sure I could build a harness that's a stand alone as I do with my lsx swaps I've done but it seems easier than that If you have the correct harness.
 

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2005 chevy trailblazer_ls
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Okay so I just looked on alldata and the pn for the bcm is the same for the 5.3 as the 4.2 which makes me think even more this swap wouldn't be too hard.

Also if a 4l60 in a z71 holds up why wouldn't it work fine in a trailblazer? Gonna go pull the tcm tune outta my tb to look at the parameters to see if they are really different than say a 05 z71 I'll let you know what I find on that.

Gm was cheap or lazy and usually most parts are very interchangeable to save on costs and engineering.
 

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2007 chevy trailblazer_ls
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The 4L60E works fine with the 300JP 5.3L that you're talking about... It's a bit under-built in stock form, for the 400HP 6.0L LS2 that this thread is about, though... IIRC, the GTO weighs ~1000# less than this vehicle does, and has less weight over the rear wheels, so is able to put less power to the ground (given the same tires), and therefore, less drivetrain stress... There is a reason that AWD vehicles (think WRX or DSM) go through transmissions when you beat on them...

IIRC, stock 5.3L exhaust on these is the same as the stock SS exhaust...

Mike
 

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2005 chevy trailblazer_ls
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The 4L60E works fine with the 300JP 5.3L that you're talking about... It's a bit under-built in stock form, for the 400HP 6.0L LS2 that this thread is about, though... IIRC, the GTO weighs ~1000# less than this vehicle does, and has less weight over the rear wheels, so is able to put less power to the ground (given the same tires), and therefore, less drivetrain stress... There is a reason that AWD vehicles (think WRX or DSM) go through transmissions when you beat on them...

IIRC, stock 5.3L exhaust on these is the same as the stock SS exhaust...

Mike
The weight isn't that far off. My wifes 05 gto at race weight with me in it is 3973. My friends 08 awd ss with me in it is 4721 on the same scale. I do agree weight kills but the 4l60 is still a strong trans if tuned correctly.

The 100hp differance from 5.3 to 6.0 isn't really 100hp. From all 4 of the rwd tbss's I've tuned made 280 or less to the tires stock.
This engine in stock form is very under tuned. I can't imagine stock to stock the 5.3 REALLY is only making 180 to the tires. Not possible.

The last 5.3 truck I tuned stock did 252.7rwhp and 291.9rwtq which is only 30hp off from the last 07 rwd tbss I tuned.

I'm not trying to start a war just am puzzled as to some of the logistics.
I'm really wanting to do this but in some respects still scared..
 

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Wow, I thought those were more like 3500#... You're still talking a 700# difference, though, plus the extra traction that's hard on parts...

Like you say, though, the 4L60E can be built to be plenty strong, but either way, you're either looking at building up a 60 or going with something stronger, all together..

Mike
 

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2005 chevy trailblazer_ls
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Wow, I thought those were more like 3500#... You're still talking a 700# difference, though, plus the extra traction that's hard on parts...

Like you say, though, the 4L60E can be built to be plenty strong, but either way, you're either looking at building up a 60 or going with something stronger, all together..

Mike
The goats are fat as crap lol.. Wife's car still runs 11.20's though cam only and 150 shot. Mines a lil or guess much faster
IMO I'd stick with the 4l60 til it broke then build a tranny. I'd make sure you get a good tune. It seams that everyone is very very scared of this swap.

Guess I need to try it for myself lol. I have a real bad 408 laying around but think I'm gonna start with cammed and ported headed 5.3.

Bartonmd are you sure the exhaust is the same on the denali?? I thought that was the reason the 5.3 gets rated at 300 Vs 325. As the trucks are.
 

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Bartonmd are you sure the exhaust is the same on the denali?? I thought that was the reason the 5.3 gets rated at 300 Vs 325. As the trucks are.
No, it's just what I gather...

Though I know it's different than the trucks, but I gather the Denali and the TBSS are the same...

Compnine says the headers/cats are the same... They don't have a part number for the rest of the exhaust on the 5.3, so I don't know... I suspect the headers may be different between the 2, but have no proof either way.

Mike
 

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Nice find! These guys might be able to build a better electric fan wiring kit that works.
IIRC, The PCM4less kit worked (electrically), but they had so many questions on the install that they stopped selling them...

Mike
 
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