NEED HELP 06 Trailblazer EXT 4.2 Engine swap

[Rick]

Need some help and advice. My water pump went out and blew a head gasket while on a trip home. Not sure about the head condition but the Engine still cranks. Had TB towed to shop which is 2.5 hours from my home. Hard to work on it when it's so far away. The shop will not replace the head gasket as they are worried about bolts breaking off and warranty issues afterward and recommending a swap with a used engine. I have seen links to auction sites to buy used TB for a used engine. I have only done one engine swap in my life and would like this to be as easy as possible. Can anyone tell me or point me to a place where I can find year, make engines that would be compatible with my TB? 06 Trailblazer EXT, 4x4.

When searching for an engine, I know I can search for a direct swap vehicle at an auction, but what would I search for if I am looking for one that is already pulled? Is there an engine spec number of some kind?

 

[Mooseman]

I don't know why they're so resistant to pulling the heads. I did it on my 9-7x and no issues at all. I think they're trying to fleece you into an engine swap rather than a head gasket job. And if you do get the heads taken off, I would also do a DOD/AFM delete while you're there and get it tuned out. Or if it's still working fine, I would at least get it tuned out to prevent a future failure.

If you do go ahead with an engine swap, you can also use an iron block from a truck, which may be a bit cheaper than the aluminum LH6. Only penalty is an extra 60 lbs or so and AFM will have to be disabled via a tune since it wouldn't have it. Not exactly sure of the years but I think the LM7 up to 07 would work. I think @TollKeeper knows more about this than me but I did find this guide.

LS Engines 101: An Introductory Overview of the Gen III/IV LS Engine Family

Learn what is an LS engine and find out basic information on this popular engine family. The article includes LS model names, RPO codes, and a list of LS engines.

www.onallcylinders.com

 

[TollKeeper]

For me to give an accurate answer, I need to know the 8th digit of the VIN.

Being that its an 06, its likely an 58x engine, but the 8th digit tells all!

This is for a V8 only... Same with @Mooseman link above..

https://www.onallcylinders.com/wp-content/uploads/2018/04/05/LS-LT-Reference-Guide-Summit-Racing.pdf

If you have a 4.2 LL8, @Mooseman is the best option. I am not all to familiar with this engine. I know enough to get me in trouble. LOL

 

[TJBaker57]

For me to give an accurate answer, I need to know the 8th digit of the VIN.

Per previous messages it appears it is a 4.2 ll8.

 

[TollKeeper]

Editted my post above to reflect that bit of info.. @Mooseman is the best for engine crossing than me on this engine!

 

[TollKeeper]

If you have the LL8, I dont blame the shop for not wanting to do a head gasket. Pain in the ass on this engine. A blown head gasket is also hardly ever heard of on this engine!

 

[Mooseman]

He does have "LS Engine Swap" in his title. @Rick , If you're talking about going from the 4.2 to an LS engine, it's a pretty involved process that has been covered here in the past.

 

[Rick]

Shop states that their experience on this engine is too many bolts break off when removing head...so they don't want to do it. With 225k miles and the potential of busting bolts off, their recommendation was a lower mileage engine swap. Which they had sight on one with low 90k mileage.

@TollKeeper The eighth digit of my VIN is an "S"

@Mooseman, I have the 4.2l 6 cylinder. I don't know if I am going from LS to LT...I don't know the difference. I believe my EXT is the LS version, but I don't find that label anywhere, but from the front end, I believe it is the LS.

 

[Mooseman]

OK, that makes more sense. I changed the title of the thread to avoid any further confusion.

The shop is right for not wanting to do the head on the 4.2 and that's what we also recommend here.

Year interchangeability is located here:
4.2L interchangeability by years

 

[TollKeeper]

So lets go back to basics.. not trying to talk down, just to provide the acronyms, and terminology, needed for this to be less stressful.

LS and LT, generally, refer to trim levels, and, generally, have nothing to do with the engine.

You do not have LS ENGINE. You have a LL8 Vortec. LS Engine (not trim) refers to the V8 engines found in most GM truck's from about 2000 to current. But yours is not one of them. Most of the GMT360, probably 90% of them, have the engine you have, the LL8, Inline 6 cylinder.

A LS ENGINE swap is possible, but not really recommended. Its a hell of a job. Its easier to take your body off your truck, and put it on a truck with the LS engine, than it is to swap a LS engine into your truck. No joke.

The shop is correct about head bolts breaking. They do, and will, and its a job to get them pulled. Than you have to replace them, as they are torque to yield. In other words, they are designed to stretch when the initial head is installed.

A 90k mile engine is really good miles. But I would be leary about a shop that says "we happen to have one of those". Is it still in a truck? can you hear it run? What year is the truck it came out of, as some years DO NOT swap to other years, even though the engine is still a 4.2 LL8.

At 225k miles, what condition is the transmission in?

How much are they charging to swap to the new LL8 engine?

 

[Rick]

OK, that makes more sense. I changed the title of the thread to avoid any further confusion.

The shop is right for not wanting to do the head on the 4.2 and that's what we also recommend here.

Year interchangeability is located here:
4.2L interchangeability by years

Thanks!! Appreciate the confirmation of the shop.

 

[Rick]

So lets go back to basics.. not trying to talk down, just to provide the acronyms, and terminology, needed for this to be less stressful.

LS and LT, generally, refer to trim levels, and, generally, have nothing to do with the engine.

You do not have LS ENGINE. You have a LL8 Vortec. LS Engine (not trim) refers to the V8 engines found in most GM truck's from about 2000 to current. But yours is not one of them. Most of the GMT360, probably 90% of them, have the engine you have, the LL8, Inline 6 cylinder.

A LS ENGINE swap is possible, but not really recommended. Its a hell of a job. Its easier to take your body off your truck, and put it on a truck with the LS engine, than it is to swap a LS engine into your truck. No joke.

The shop is correct about head bolts breaking. They do, and will, and its a job to get them pulled. Than you have to replace them, as they are torque to yield. In other words, they are designed to stretch when the initial head is installed.

A 90k mile engine is really good miles. But I would be leary about a shop that says "we happen to have one of those". Is it still in a truck? can you hear it run? What year is the truck it came out of, as some years DO NOT swap to other years, even though the engine is still a 4.2 LL8.

At 225k miles, what condition is the transmission in?

How much are they charging to swap to the new LL8 engine?

Thank you for the explanation and clarification!! I knew the LS is the trim option but didn't know if it crossed over to other "options". I do not want to go to the V8 (LS engine) especially if it is as difficult as you describe. Don't have time for that.

I don't know where they were seeing a 90k mile engine, they were just pricing it out at $7800. Which is too much for me to put into it, which is why I am looking at doing it myself.

My 225k transmission is in good shape. I haven't had any issues with it. 4x4 works great too...Have been working to do some "upgrades" (suspension, lights, bumpers). Like the truck and have been through it so much that I don't know if I want to relearn a new one. LOL!

Thanks for your help!

 

[TJBaker57]

they were just pricing it out at $7800. Which is too much for me

That is plain batshit crazy.

 

[TJBaker57]

Had TB towed to shop which is 2.5 hours from my home

This is a case where a premium AAA plan would be really handy. 3 times in the past decade I have been towed just under 200 miles FREE as part of the annual membership that costs me $120. For 250 miles I would only have to have paid for the 50 miles over 200.

 

[Rick]

This is a case where a premium AAA plan would be really handy. 3 times in the past decade I have been towed just under 200 miles FREE as part of the annual membership that costs me $120. For 250 miles I would only have to have paid for the 50 miles over 200.

Towing is part of my USAA plan, but only for 50 miles. This whole breakdown was a crazy freaky story that has been hard to believe. The truck broke down in a middle of now where spot between Phoenix and Tucson, much closer to Phoenix than home. Called insurance for towing...35 min arrival. Told me I needed to get to a safe place being I was on the highway after dark. Said that the tow company wouldn't let me ride with them due to COVID protocols. Which is crazy as AZ is very open and over most all this. Called my wife who graciously came to save me, hour and 45 min drive for her. 45 minutes, the first tow company texts me, says they can't find vehicle (which I am sitting in), and gave up. Called insurance, dispatched a second company, says they are about 90 mins out. Being truck won't start, insurance tells me to leave keys in the truck for towing company. Told them I have no way to get anywhere without the tow vehicle. Said they would send a Lyft for me. Asked me for my address. Told them, I-10 at mile marker 179. Said the Lyft won't stop along the highway...I needed to get for the highway. After some words, told them I didn't have time for this nonsense. Packed up my backpack, and duffle bag and proceeded to walk the 7 miles to the next exit and meet my wife there at a turnaround. Made it halfway before my wife got to me. Got a text at 1:30 AM that a third company actually got the truck and towed it to the shop it is at now. Needless to say...not a good time. Still sore from walking in the dark, carrying a load like that. haven't done that in a long time. My bitchin is over...carry on.

 

[Rick]

OK, that makes more sense. I changed the title of the thread to avoid any further confusion.

The shop is right for not wanting to do the head on the 4.2 and that's what we also recommend here.

Year interchangeability is located here:
4.2L interchangeability by years

I checked out your link and all I see is that the 06 to 09 are directly interchangeable....Is that correct? Are there other models that have this same engine that would be good for a direct swap?

 

[TJBaker57]

I checked out your link and all I see is that the 06 to 09 are directly interchangeable....Is that correct? Are there other models that have this same engine that would be good for a direct swap?

NO!

02 to 07 can be made to work. 08 or 09 cannot be made to work in your 06.

 

[Reprise]

I-10... how far are you from Quartzsite? And how soon do you need this work done?

I'm planning on being out that way after Thxgiving. If you find an engine, I can put it in. Or I could swap the head (yes, I know the bolts tend to break).

Downside is that I'm more familiar with the V8 than the I6, but I'm not frightened by the task, or I wouldn't make the offer. And I have this community to lean on w/ any questions I run into.

I can offer 'cheap' and 'good'... but not 'fast'.

 

[TollKeeper]

That's a hell of an offer @Reprise !

Here's his next problem, getting that truck from where it is, to somewhere he can with on it. I would suggest a friend or family member, if they have a truck, borrow it, rent a U-Haul, and get her home. That is likely your most cost effective solution.

Next problem.. how much does this shop want to get it out of the shop..

 

[Mooseman]

I have done an LL8 engine swap and it's no walk in the park. Not to discourage anybody but there are extra steps like the front axles, the rack and pinion and tight areas before you can yank it out. I did learn a trick or two on doing it. Took me a month however I was doing it outside in a hot blazing July sun on days off from shift work. That being said, it's still easier and less hassle than the head swap.

Yeah, that shop is either smoking some bad crack or trying to fleece you due to your situation. You can buy a good whole truck for that! If you can find an engine or a whole truck locally, even having to tow yours home, would be much more reasonable. Just remember that if you do get a whole truck, it will double your work, having to also pull the replacement engine out of the donor.

@Reprise , that is HUGE offer. Love this place!

 

[TollKeeper]

NO!

02 to 07 can be made to work. 08 or 09 cannot be made to work in your 06.

@Mooseman , hopefully the info is correct this time..

For you, an 06-07 are a direct swap, no modifications needed.

02-05 can be made to work, with not a lot of work. They moved a couple sensors, so wires need to be extended.

08-09 is no go. Major sensors for the crank and cams changed, and these cant be easily modified without complete disassembly of the engine.

@Mooseman - what about the sais on those older engines, what needs to be done there?

 

[Mooseman]

SAIS is a direct swap in even on the engines that didn't have it as the provisions are already there.

All your other info is correct

 

[Rick]

I-10... how far are you from Quartzsite? And how soon do you need this work done?

I'm planning on being out that way after Thxgiving. If you find an engine, I can put it in. Or I could swap the head (yes, I know the bolts tend to break).

Downside is that I'm more familiar with the V8 than the I6, but I'm not frightened by the task, or I wouldn't make the offer. And I have this community to lean on w/ any questions I run into.

I can offer 'cheap' and 'good'... but not 'fast'.

Thank you for the offer, that is very generous of you and I appreciate it! Unfortunately, I am in the opposite direction of you. The truck is being transported from Phoenix to my location tomorrow, which is south of Tucson by 30 minutes. Thank you again!

 

[Rick]

That's a hell of an offer @Reprise !

Here's his next problem, getting that truck from where it is, to somewhere he can with on it. I would suggest a friend or family member, if they have a truck, borrow it, rent a U-Haul, and get her home. That is likely your most cost effective solution.

Next problem.. how much does this shop want to get it out of the shop..

Shop charged a $75 diagnostic fee. Shipping it home is $300 being it needs to be winched up on a trailer. Not too bad. Can't go get it myself right now. Then we will see what I find as far as a replacement engine.

 

[Rick]

Has anyone everyone ever bought a car on copart auction site? Costs $59 to sign up to bid. Anything I should be mindful of?

 

[TollKeeper]

I have bought a few on there. There are things to be mindful of. The price you bid, is not how much you are going to pay. There are fees!

https://www.copart.com/member-fees-us-non-licensed/

Auction fee, listing fee, etc.

Be very mindful of the location. Just because it says its in One State, doesnt mean it is. A particular auction will have secondary lots.

I bought a car in Denver, but the car was actually in Grand Junction.. Just 250 miles away!

 

[Rick]

I have bought a few on there. There are things to be mindful of. The price you bid, is not how much you are going to pay. There are fees!

https://www.copart.com/member-fees-us-non-licensed/

Auction fee, listing fee, etc.

Be very mindful of the location. Just because it says its in One State, doesnt mean it is. A particular auction will have secondary lots.

I bought a car in Denver, but the car was actually in Grand Junction.. Just 250 miles away!

I am required to join and login to see the link you provided. May do that later tomorrow. How do you determine the location of the vehicle versus the auction location?

 

[TollKeeper]

 

[Reprise]

Thank you for the offer, that is very generous of you and I appreciate it! Unfortunately, I am in the opposite direction of you. The truck is being transported from Phoenix to my location tomorrow, which is south of Tucson by 30 minutes. Thank you again!

No worries
I just looked up Tucson, and you're in a different 'quadrant' (Qz is SW, Tucson is SE (almost in Mexico, which means I'd probably have been in for a sweaty experience similar to Moose when he did his swap). Just a little bit far to travel back / forth. Although I could've stopped on the way, as I'll be driving down from IL.

Good luck with locating a different engine / getting it swapped in.
Whatever you do, don't spend $7800 on it!

 

[Djsaggs]

I just did an engine swap in my 2003. Bear thing I ever did

 

[NJTB]

Did you ever get the engine swapped, or buy a new car?