47-55.1 Chevy 3600 5.3 LH6

[1953]

Hey guys second post here been planning my build out and i decided to go with a 5.3 LH6 out of a 07 trailblazer with 87k miles engine runs great its coming out of my daily driver its in great condition, has anyone used one of these motors in there trucks? I decided to go with front ifs cnotch in the rear keeping the truck long its a 3600. Anyone with some good tips on these LH6 engines id love to see and hear about your experiences.

[mongocanfly]

I think you'll have to change the oil pan ....you should be good to go...really no diff than any other LS swap...

[1953]

I figured it was pretty much like any LS i cant seem to find anyone who has used one in our trucks this TB has been sitting around my yard for over 2 years now i dont drive it much any more and finally decided its time for a V8 in the chevy lol will probably get a stand alone harness for it and maybe cam upgrade and build it up i will be using a bolt in IFS from speedway i think maybe the weld series if i can find somone to weld for me i dont feel comfortable welding a major assembly like that i weld but nothing to that degree

[mongocanfly]

I cant recall who or in what yr truck ,but I know theres several TB/LS engines in use here

[whitedog76]

If I recall, that's an aluminum block engine, same as what was used in the Escalades. My sister and my dad have both owned V8 Trailblazers. They both have had lifter and rocker arm trouble due to the cylinder deactivation setup.

There's no lack of LS swaps here, so I don't think you'll have any surprises.

I believe the Trailblazer is a front sump engine, so you'll have to jump that hurdle. I know that on the I6 Trailblazers, the TAC module and Trans control module was integrated in the ECM until the 08/09 models, so the V8 might be the same.

[1953]

Yes its all aluminum block, ive actually known one other person to use one in a monte carlo ss he had his set up pretty nice, yes its a front sump, and the cylinder deactivation setup i believe your referring to the displacement on demand ? I looked into that and they have a delete kit thats fairly easy to do, i was going to do that on the TB when i used to drive it and put a cam but it being a fairly cheap vehicle to own i decided not to build the engine up i think this engine is going to be pretty sweet in my 3600 with IFS and possibly a 4 link in the rear? Still weighting in on the rear options c notch seems more realistic for my budget, another thing is i would like a 6x5.5 bolt pattern if possible i have a beautiful set of trailblazer SS rims id love to incorporate, i am wondering about my transmission options the stock TB trans i am considering but not even sure what trans is in it havnt got down to look yet haha but i want a manual trans and i will need to figure out what trans will go well with the LH6 5.3 im very excited to get this going but i want to be totally prepared id love to be driving in the spring, i could drive now as all original 3600 but that was my dads style (R.I.P) not mine lol i do want somthing diffrent then the 3100 and other 3600s i want it long and lowered now air bags even later on i hope the speedway motors crossmember is a good choice cause that looks like the winner for me, this truck will never haul another load so hoping the bolt in works out they say they fit 3/4 ton on there website.

[joedoh]

trailblazer ss are 6 on 5.


lots of LS swaps in the project section, search for 5.3, and 5.3 aluminum.

[whitedog76]

Yeah, those wheels are destined for Craigslist. The Trailblazer, Envoy 6x5 bolt pattern is shared by, well... nothing.

Your donor vehicle will have the GM 8.6 rear end. You can get some donor axle shafts from a H3 or Colorado to get you the 6x5.5 pattern. There are 6x5.5 hubs available for the M2 spindles.

[1953]

Here is somthing intresting, i measured the width tire to tire on my donor trailblazer rear end and went and mesured the same on my 3600 and they was both 71' ish very close i went from edge of tire to edge of tire if the wheels wasnt still on i would have mesured it correctly, i wasnt aware that the trailblazer rear ends are darn there spot on with the stock 3600 rear diff, so my next idea is using it lol what do all of you think? Im using the motor forsure and possibly the trans thats if i dont find a good manual trans, im pretty set on doing a c notch in the rear, drive shaft length might be a issue im thinking. A big issue i have is my rear stock leaf spring hangers and pins are completely siezed up the last time i had the bed off and tires off i tried to remove them and they are siezed into the shackle and hangers any solutions for getting those un siezed ? Spring eye bolt i believe there called lol "still learning alot about this truck"

[joedoh]

i havent done one, so take it with a grain of salt, but there are a few trailblazer swaps (where they use the whole frame and drivetrain together) in the projects sections and the general feeling is that trailblazer axles are just too wide for an AD. better fit with the TF (55.2-59). even with the stock TB wheels.

search trailblazer in projects.

edit: here is BBEEPs panel, trailblazer axle (envoy actually) with the fender moved out 1/2 inch




staying around/under 65" is really a better width for an AD

[1953]

That is pretty close to fenders lol

[1953]

The track width to a 07 trailblazer LT is believe it or not 62.1 i double checked so the 71 measurement i had was off but im really debating trying it out lol

[whitedog76]

The HO52 that's under your truck now is 62.5 WMS to WMS, which is basically the same as the TB.

I also have a TB donor vehicle sitting in the driveway. I've been trying to convince myself to use the rear instead of an 8.8, but that darn oddball bolt pattern muddies things up.

[e015475]

I have an aluminum 5.3 out of a Trailblazer in my '49

It is the earlier LM4, not the LH6, so I side-stepped the cylinder deactivation issue.

One thing that was a little odd about my engine was the oil dipstick was in the pan, not the block. To fit a truck pan with a rear sump I had to drill the block to accept the dipstick tube. There was a boss cast into the block for it. but no hole machined.

You might want to check your engine and see where the dipstick is mounted.

[joedoh]

thats good news, if you are doing a MII front end be sure to consider the front track width, when I see a truck with a ZR2 rear (63") and a MII front end, the rear wheels seem to be way out in the fenders and the front wheels way in. good for turning, but just my opinion looks like a tapered frame.

[1953]

If I may ask what is so odd ball about the bolt pattern? And I am checking into this sump today going to start engine removal process on 3600 front fenders I won't be able to get to the bolt in crossmember for a while looking like November but in the meantime I want disassemble get my motor situated start on the C notch in the rear next after that, the dipstick looks to be mounted on the left side of the engine not sure where it runs too at this point but it's definitely running downwards it looks like it curves towards the engine can't be for certain it's hard to see down I just looked at the sump and it looks to be a front sump oil drain plug dead center of the sump

[whitedog76]

Originally Posted by 1953

If I may ask what is so odd ball about the bolt pattern?

The 6x5 pattern is unique to Trailblazer, Envoys, etc... No other car or truck uses that pattern. If you want to use those wheels on your MII front, you'll have to use a wheel spacer/adapter setup. TCI, and CPP have a 6x5.5 hub for the MII, so you can get an adapter to go from 6x5 to 6x5.5.

[joedoh]

take the front end off as one piece, fenders+inners+grille+core support. there is no reason to break it down, and its easier to store as one big chunk. unbolt the inners from the firewall, the fenders from the cab, the rad support from the frame. you may need to pull the bumper as well.

disconnect rad hoses and wiring (the wiring is likely shot, so cutting is fine). get a friend and lift it.

if you choose to take it all apart, drill alignment holes in everything before unbolting, so at least you can line it all up when you put it back together.

[dsraven]

here is a link to a tf truck with a trailblazer frame under it. the wheels are def into the fenders unless you downsize the diameter or flare the fenders.

http://67-72chevytrucks.com/vboard/s...d.php?t=653590

[dsraven]

if you have the skills to do the frame swap then adding some width to the fenders will likely not be an issue.
on the v8 trailblazers the tac module is on the firewall near the brake booster. on the inline 6 4.2l it is built into the ecm i believe. the oil pans on both engines have a hole through them horizontally to allow the front diff and cross shaft to be bolted onto the oil pan. they use the same oil pan on the 2wd models i think. a new oil pan, oil pick up tube, dipstick and tube etc could be used from, say, a camaro. I don't think the block is trailblazer specific. more research on that would be good.
these guys have some good info with lots of oil pan pics etc. what years were what etc. there are 2 parts to the ls primer atrticle on that site.

https://www.pirate4x4.com/tech/billa...SPrimer/Part1/

[dsraven]

here is an ad unit on trailblazer frame

https://www.mecum.com/lots/FL0115-20...to-mod-pickup/

[mr48chev]

Frame swap would give him more headaches then he is up to. Leave the frame swaps to Joedoe and the other guys who know the ins and outs and have the experience and equipment to do them.

I agree with Joedoe, remove the front bumper and brackets off the 3600 and remove the nose assembly as a unit. I've done it several times on my 48 and other trucks. You do need a helper to make it easier but it can be done by one person. It is also easier if the wheels and tires are off.

The bolt on MII front end just takes a 1/2 inch drill and a hand full of wrenches and a good tape measure. You need to make the notch in front of it to clear the steering but that can be done with simple tools too. The inner fenders need a bit of trimming for clearance but that is it.

Personally after I pulled the engine and a few other pieces I'd sell the trailblazer as roller and use the money to buy a rear end with less hassle to fit.

[dsraven]

for clarity,
I wasn't condoning the frame swap either, just some pics to show the width difference. it would be a lot of work especially on an AD. just saying IF a frame swap was done then adding some width to the fenders would be a piece of cake in comparison. meaning, adding some width to the fenders is not normally a piece of cake either for most of us, lol.

agreed with mr48, bolt in ifs is quickest, easiest and less likely to get messed up compared to a weld in unit, even if you have the right stuff and know how IFS geometry is supposed to work.

[1953]

Yeah im not doing a chassis swap i have the abilitys, i thought about it but i have a perfect frame as is no need for a swap with Mll ifs and all the upgrades they have now. And yes im going to sell the TB chassis as a roller or it may just be my next project after this one, and yes i agree also removing front as one piece, ive worked on this original chevy my whole life pretty much, very familiar with it and updating the engine and suspension shouldnt be to hard on me ive spent a good part of my life building motorcycles, my only down fall is welding my welding skills end at exaust welding pretty much lol but i can lay a bead pretty well, its a art form for sure knowing your penetration and proper set ups, i may find somone to do my c notch welds appreciate everyone advice really helpful and inspiring

[b-mac]

I'm not certain, but I have the 5.3 from a Buick Rainer. I think it's the same as what you have.

They have a somewhat unique DBW system. You could yank it all out, but if you don't want to change the throttle body, I think you'll need to do what I did.

See this thread below:

http://67-72chevytrucks.com/vboard/s...d.php?t=763040

Specifically, post #17