Thinking about Trailbalzer

CrazyDrei

Space Monkey
Mom's '02 had IRS, the entire discombobulated mess of a rear axle/suspension was a joke.

It rode nice when it wasn't broke. PITA to work on (the sealed wheel bearings have to be pressed in an out of the knuckle with a shop press) rear axleshaft leaks, driveshaft vibration, struts broke... on a pavement pounder that usually only carried two people and never saw a trailer. Just yuck.

I don't care about the front (I do like the real wheel bearings and lockouts on my Ranger's IFS) but gimme a solid rear axle any day over an IRS for a truck.

85_Ranger4x4,

Well, that just burst my tiny little bubble of hope for Ford IRS, thanx.
 

85_Ranger4x4

Well-known member
85_Ranger4x4,

Well, that just burst my tiny little bubble of hope for Ford IRS, thanx.

It would have its merits but most are built more like something out of a minivan than like what is in a humvee.

There is just so much less to go wrong with a solid axle if you keep good oil in them. Literally so far the rear axle in my Ranger has outlived its original host by 14 years and counting. I have done nothing but put seals in it and replace the limited slip clutch packs before I swapped it in. I guess I did change the oil and put a neater diff cover on it over this past summer. All the bearings looked new before I put it in the truck and it still runs silent and smooth on the highway. They just work.

For something that runs heavy I do like that the wheel bearings run in oil. Like mom's Explorer we had to put three rear wheel bearings in it. After all the fun of replacing one and then the new one dying within two months... you bet we did an autopsy on the bad one. New Timken... the poor thing had very little grease in it from the factory. It is a sealed thing you have to destroy to open up so there is no way to know exactly what you are getting until they start talking to you.
 

Todd780

OverCamper
Is this the Trailblazer build you were referring to?

 

1stDeuce

Explorer
1stDeuce,

Wow, thats pretty much the kinda feedback I was looking for, thank you very much.

I am aware of the front diff oil pan mounting, weird as all hell. I am also thinking about one with a 5.3 motor just because thats what I am very familiar with and can tune it to be exactly how I like it. Not sure about the front diff configuration in the V8 vs I-6. If you know anything about that let me know.

Interesting you mention how tail happy it gets even with the 3.73 gears.

Tell me more about the 3" body lift, you mentioned that it's pretty hard on stuff, what stuff is it hard on?

I know that I want to play with a GMT360/370 platform, but not really sure which direction I want to go with it. I either want to do bad and stupid things with it and build it as a dedicated 4x4 trail rig (with GM IFS, I know, feel free to give me crap about this one) or a really screwed up "practical" backroad 2wd street legal truck. In either case I want at least 35" tires on it.

I think that I am narrowing my search down to a TB with 5.3, I might have to pay a premium for it but with all the parts I have laying around it will be a huge savings over the entire build.

The 5.3l also has the diff mounted to the oil pan.

The gear ratio has nothing to do with the tail happy bit... On slick roads, it is notable that the transfer case waits to engage the front axle until the rear axle slips, and it's kinda "sloppy" compared to the auto transfer case in pickups. If you happen to be turning a corner, or at an intersection, and the rear tires slip some as you tip into the throttle the rear starts to slide out before the front starts pulling. (A spinning tire has no lateral grip.) It can be kinda fun once you know it happens, and stability control will help catch it when it happens if you are an un-suspecting driver. As this is an early platform for stability control, the system is tuned to be "safe" vs. fun... It unfortunately tends to be a bit heavy handed with throttle reductions if the going gets loose. Again, this is 2006+ only. Earlier trucks had no traction control, except perhaps some 2wd trucks with engine only TC. (Not recommended...)

I don't think a 3" body lift is especially hard on anything. I was perhaps unclear when I said 2" max, but I was talking about lifting the front suspension more than about 2" as being hard on things like CV joints, tie rod ends, and ball joints. 3" is, IMO, asking for trouble, and the only way to do this is to greatly reduce droop travel from static ride height. This will make the truck ride pretty harsh, and results in limited suspension travel in a practical sense, as your "normal" ride height is so close to full droop.

The 3" body lift will look pretty bad, IMO, as the frame is already hanging down below the body quite notably. at 3", you would be looking at the full frame below the body. A 1" or even 2" body lift might be an option for a little more clearance.

Honestly, if you think you HAVE to have 35's, I would recommend that you're looking at the wrong platform. Those are, IMO, HUGE tires for a small SUV, and you're going to end up with a POS that drives like crap, and doesn't work well offroad anyway. Gearing is going to be pretty terrible, as it's unlikely you'll find a 4:10 V8. If a wheelin only rig is what you want, then forget lift and just whack the fenders till those tires fit, but that's not really expo style, it's Pirate4x4 stuff... I'd have to take another look, but I don't think 35's will package even if you remove the front fenders... Seems like other body parts are well in the way, like rockers, floor, radiator support, and perhaps even the frame... Going to a wider offset wheel gets tires away from the frame, but then they swing an even bigger arc into the floor, radiator support, etc. The 6 on 5" bolt pattern for TB is pretty specific to that platform, limiting aftermarket wheel selection, but the 17" wheel is pretty wide, so you could run a decent size tire on it.

There is a thread here where a guy has a 370, and he's got about 3" of lift at the front. I think he's running a 32 or 33" tire. Perhaps he would have more wisdom for you... https://expeditionportal.com/forum/threads/my-04-trailblazer.216113/

Hmm. Here's what you're thinking of I bet... Older thread, but good info and ideas, and he's got 35's on a TB: https://blazerforum.com/forum/lifting-tech-44/2006-trailblazer-35s-57926/

If you do this, you better start a build thread!! :)
 
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CrazyDrei

Space Monkey
Is this the Trailblazer build you were referring to?


Todd n Natalie,

HARDTRAILZ!! Yes, that is the one! I've talked to him about several ideas I had rolling around in my brain and everything sounded very doable and promising with what i want to do.

It looks like he did pretty much the same thing with his TB as I did with my Suburban.
 

CrazyDrei

Space Monkey
The gear ratio has nothing to do with the tail happy bit... On slick roads, it is notable that the transfer case waits to engage the front axle until the rear axle slips, and it's kinda "sloppy" compared to the auto transfer case in pickups. If you happen to be turning a corner, or at an intersection, and the rear tires slip some as you tip into the throttle the rear starts to slide out before the front starts pulling. (A spinning tire has no lateral grip.) It can be kinda fun once you know it happens, and stability control will help catch it when it happens if you are an un-suspecting driver. As this is an early platform for stability control, the system is tuned to be "safe" vs. fun... It unfortunately tends to be a bit heavy handed with throttle reductions if the going gets loose. Again, this is 2006+ only. Earlier trucks had no traction control, except perhaps some 2wd trucks with engine only TC. (Not recommended...)

Sounds like it behaves like a worn out NP246 transfer case in a full size truck thats always run in auto mode. Scarry at first, then fun and then just annoying.

I don't think a 3" body lift is especially hard on anything. I was perhaps unclear when I said 2" max, but I was talking about lifting the front suspension more than about 2" as being hard on things like CV joints, tie rod ends, and ball joints. 3" is, IMO, asking for trouble, and the only way to do this is to greatly reduce droop travel from static ride height. This will make the truck ride pretty harsh, and results in limited suspension travel in a practical sense, as your "normal" ride height is so close to full droop.

Gotcha, realistically even with a upper control arm flip I don't think going more than 2" up front with either spacers or 5100 B8 shocks. Tie rods will get sleeves automatically, would have to look into the tie rod ends themselves but I generally pick my line very carefully and intentionally. I have played with different droops in my Suburban and reducing the downward suspension travel makes the ride unberably harsh and puts so much extra and unnecessary strain in the suspension parts. That would probably need to vehicle specific tinkering to find a sweet spot.


The 3" body lift will look pretty bad, IMO, as the frame is already hanging down below the body quite notably. at 3", you would be looking at the full frame below the body. A 1" or even 2" body lift might be an option for a little more clearance.

Yes 3" body lift will look horrible with the frame showing however there are ways around it such as running board or sliders to make it look prettier, not too worried about that aspect of the looks.

Honestly, if you think you HAVE to have 35's, I would recommend that you're looking at the wrong platform. Those are, IMO, HUGE tires for a small SUV, and you're going to end up with a POS that drives like crap, and doesn't work well offroad anyway. Gearing is going to be pretty terrible, as it's unlikely you'll find a 4:10 V8. If a wheelin only rig is what you want, then forget lift and just whack the fenders till those tires fit, but that's not really expo style, it's Pirate4x4 stuff... I'd have to take another look, but I don't think 35's will package even if you remove the front fenders... Seems like other body parts are well in the way, like rockers, floor, radiator support, and perhaps even the frame... Going to a wider offset wheel gets tires away from the frame, but then they swing an even bigger arc into the floor, radiator support, etc. The 6 on 5" bolt pattern for TB is pretty specific to that platform, limiting aftermarket wheel selection, but the 17" wheel is pretty wide, so you could run a decent size tire on it.

Yes I want 35s or 37s, I was also told that very same thing about my 2000 Suburban which runs 37s with no rubbing and no lift and it looks like nothing on pirate and everything on ExPo. I think I should be able to make 35s work and fit tastefully. Also I am not too worried about gears, my cost is $120 per end for any gearing I want, and should take a couple hours to swap them myself as well as either put a full spool or lunchbox in the rear axle.

I am quite concerned about 6x5.0. I would have to run spacers/adapters along with correct wheel backspacing/offset to maximize wheel travel, minimize rubbing, elliminate binding and find the optimal scrub radius. I saw that putting GMT800 front wheel hubs would require some machining which I don't have access to, but the rear end could be a direct 8.6 axle swap.

There is a thread here where a guy has a 370, and he's got about 3" of lift at the front. I think he's running a 32 or 33" tire. Perhaps he would have more wisdom for you... https://expeditionportal.com/forum/threads/my-04-trailblazer.216113/

Saw this build, waiting to see some pictures of his truck in action, he is a fellow Mainer like me might have to met up with him and check out the truck and pick his brain.

Hmm. Here's what you're thinking of I bet... Older thread, but good info and ideas, and he's got 35's on a TB: https://blazerforum.com/forum/lifting-tech-44/2006-trailblazer-35s-57926/

Yep, HARDTRAILZ followed a similar path of greatest resistance building his TB as I did with my Suburban, I have been picking his brain and bouncing some ideas I had off him. I really like the look reminicent of 1990s Nissan Patrol trucks that he turned his into, looks really good. He has a very good idea of my TB project that I'm preparing to start in the very near future.

If you do this, you better start a build thread!!

Heck yeah! TBs and GM trucks need more a presence in the overland community.

Officially started my search for a GMT360/370 with a 5.3, hopefully I can pick one up sooner than later and start tinkering.
 

CrazyDrei

Space Monkey
Those two look pretty darn sweet! I want one, but with bigger tires ?

And you guys are officially a bad influence. I found a 05 TB EXT with 5.3 and 4x4 for a reasonable price that I'm going to look at this week.

EdoeXZZ.jpg


It is a 2005, so it's an LH6 motor with Active Fuel Management and 8.6" rear end.
 

Todd780

OverCamper
Those two look pretty darn sweet! I want one, but with bigger tires ?

And you guys are officially a bad influence. I found a 05 TB EXT with 5.3 and 4x4 for a reasonable price that I'm going to look at this week.

EdoeXZZ.jpg


It is a 2005, so it's an LH6 motor with Active Fuel Management and 8.6" rear end.
A coworker had one of these at the same time I had my 2000 Suburban. They were very close in length. So close that to me, I would rather have a Suburban vs a Trailblazer EXT.

Just my 2 cents, I would go for the 5 passenger 'shorty' if going for a Trailblazer / Envoy.
 

ExplorerTom

Explorer
85_Ranger4x4,

Well, that just burst my tiny little bubble of hope for Ford IRS, thanx.

The Expedition went IRS in 2003 (or so). And is still IRS. Able to tow a metric butt load. I’m not sure how similar the Expedition IRS is to the Explorer IRS.

I have a 2014 Expedition and have replaced the struts on it. Sure it’s WAY more involved than replacing shocks on a solid rear, but it wasn’t horrible. Had to buy a couple large sockets but otherwise it’s just nuts and bolts.

I’ve got 110k miles on it (bought it almost a year ago with 94k) and it’s been great.
 

JohnDoe

New member
The main draw is that they are still cheap for a vehicle that has true 4wd with low range. Try buying any other SUV with these specs for the price, even Xterras have gotten pricey. 35's or 37's will blow up the stock diffs pretty quickly if you actually off road it. The 8.6 rear diff is marginal, Trailblazer ss rear ends are a direct bolt on 14 bolt semi float with 4.10 gears and a limited slip. Front your best bet is solid axle.

For others looking to keep closer to stock one thing to look for is check the VIN to see the gear ratios and if it has a rear "locker". GU6-3.42, GT4-3.73, GT5-4.10, G80-locking rear diff. I have 3.73 gears with 32 inch tires and it does ok, wouldn't push it with 3.42 gears. The G80 locker takes a few revolutions to engage but it does actually work and got me out of a few situations. However these are known to have a short lifespan if abused, keep a steady throttle when you feel a wheel slip and a few seconds later it'll lock up. Mash the throttle and you'll feel the G80 explode when it gets traction.

https://www.facebook.com/MDBFAB/ makes good skid plates. https://www.bilsteinlifts.com/shop/...t-shocks-for-2002-2009-chevrolet-trailblazer/ are good for a lift, just need a rear spacer. I combined with https://www.roughcountry.com/gm-leveling-lift-kit-289.html to replace the stock front shock mounts too and kept the front bilsteins at 0" lift. Also need wheel spacers to prevent control arm rub https://www.ebay.com/itm/ECCPP-4-pc...351489?hash=item3fcbfddc41:g:CMoAAOSweDRgBkLS
 

skrypj

Well-known member
My dad has a Saab 9-7x Aero which is a rebadged Trailblazer SS with the 6.0L LS2.

Its a raging pile of crap. Im pretty sure he has replaced most of that truck at this point. Front diff blew, trans had to be rebuilt, steering rack has failed multiple times. Etc.

But, its an animal. I always love driving it when I go home to visit. Its just a burly, loud, fast truck.

Anyways, look into the 9-7x. I think you can find then more readily with the 5.3L than you can the trailblazer. Aero’s are very hard to come by as they only made 490 or them or something and only in 2008 and 2009.

One oddity is that the passenger half shaft passes through the oil pan.
 

1stDeuce

Explorer
Skrypj, I don't know that I'd recommend this as a great option, since it only has full time 4wd with no way to even lock the center diff, but it is intersting to know that there was a Saab version of the SS. I had to GTS to confirm... I didn't know it even existed, and I worked on that platform back in 2006/7.

The normal Saab 9-7x was a re-badged Bravada/Rainier, with a horrible single speed "auto" t-case. I'll have to keep my eyes open for a 9-7x Aero... Sounds like only about 500 were made... Probably big $$$ like the SS AWD's. :)
 
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