Offroad Trailblazers and Envoys

axle swap

G80, GU6, GT4, GT5, WTF? This section is for gearing and driveline stuff.

by AWCougar » Sat Dec 28, 2013 6:41 pm

so the ext came with 8.6" rear axles with 4.10 gearing... interesting.
i haven't had the time to look much
but is the ext's front differential "bolt on" as well?
just my 2 cents on the matter of a locker on the front. if the front ends with them keep locking and half shafts keep breaking... maybe it's not such a good idea to locker the front.
but on that note bigger is better and lockered up is even better on top of that so i think i might try and research more into it
"Though we have heard of stupid haste in war, cleverness has never been seen associated with long delays." -Sun Tzu

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by Conner299 » Sat Dec 28, 2013 7:07 pm

Front diff on the ext is the same as on the swb. No "diff"erence! You guys see what I did there? :lol:
I DON'T care what my GMT360 was designed to do, I care about what it can do!
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by Aries » Sat Dec 28, 2013 7:30 pm

AWCougar wrote:so the ext came with 8.6" rear axles with 4.10 gearing... interesting.

Not all EXT's. My has GU6=3.42 for now.
Last edited by Aries on Sun Dec 29, 2013 5:04 pm, edited 1 time in total.
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by The Roadie » Sun Dec 29, 2013 4:01 pm

AWCougar wrote: if the front ends with them keep locking and half shafts keep breaking... maybe it's not such a good idea to locker the front.
but on that note bigger is better and lockered up is even better on top of that so i think i might try and research more into it
[Essay mode ON]

My attitude, after doing extreme trails including part of the Rubicon with Greg (Teebes), is that you get twice the traction by airing down. If you're on a trail that you have adequate ground clearance for, and not enough traction with 2 or 3 aired-down tires, and you have to gun it to spin up some tire to get over an obstacle or overcome mud or snow, but the RPM of any tire is at risk for a sudden change due to it "catching", then you're taking a suboptimal line, or you're trying a trail that's unreasonable to try to conquer.

I don't try to keep up with or pass much better-built trucks. I don't respond to taunts, voiced or imagined. I have OFTEN backed away from terrain that's going to break stuff. My retirement looms a lot larger than my ego for trail-conquering checklists. Full-throttle is no longer in my bag of tricks unless it's needed to get out of imminent danger, and with experience I hope to avoid crumbling trails like I was an idiot to attempt years ago. And because of the law of conservation of carnage ..... if you build up some parts of the truck too much, you push the potential for damage elsewhere that may be tougher or more expensive to fix.

Thus I don't have straight, stronger tie rod ends. I think I can arrange my driving to not bend mine anymore, but if I did, I'd MUCH rather have an easy ten minute trail repair that doesn't even involve taking the tire off, than a broken steering rack, which is where the stress is going to be transferred with stronger TRE. Think of the TRE as a mechanical fuse. Same thing for front lockers. A broken CV shaft is a 20 minute trailside repair. It could even be a ten minute project to remove the broken bits and limp out in 2WD. With a locker and a broken CV shaft, you get to limp home in 3WD mode. Not a huge improvement. Fails my bang-for-the-buck mod prioritization test.

A winch and a dose of patience can replace the desire for a front locker and beefier CV shafts. That's how my experience and temperment (old fartiness and tendency towards being a relative chicken-shit nowadays) say I should be going. It's funny to think back and realize what an asshat I was when I was only 50. Or 55. I *DO* still scare the pants off my boss with a Wrangler on 33's and 4.56 gears with two lockers when he tries to follow ME. He doesn't even yet believe in the benefit of airing down. YMMV.
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