Front Diff swap

[MK-voy]

i was just looking at the ARB lockers, they produce a unit for H3,I know that envoy and trailblazer have the AAM725 aluminum diff front and H3 have AAM760 cast iron are they interchangeable.
could AAM 760 be fitted in an envoy???

[HARDTRAILZ]

I don't believe so.

[v7guy]

I believe this had been looked into a few years back and it was a negative.
At this point the only way to swap in a different diff would be to build a drop bracket with a bolt pattern for a different diff.

[MK-voy]

so u need to build a whole new front???? no other option to upgrade front dif????

[HARDTRAILZ]

Correct.

[MK-voy]

is it safe to change front gear ratio to 4.56 on the same aluminum housing

[janesy86]

Fishsticks (Donny) did it. No reason it should be a problem.

[Skindiggers]

The only problem when you change the gear is to align the ring with the pinion ... That will give you some headaches !

[navigator]

I remember Donny having problems with the disconnect, CV axles (due to tight turns after locking) and TRE.
I don't recall (but could be wrong) any issues with the diff itself.

[Trail X]

Fishsticks (Donny) did it. No reason it should be a problem.

So did AlekG.

[janesy86]

Oh ya. Forgot about him, and Tebees for that matter...

[fishsticks]

My 4.56 ring and pinion, locker, carrier and aluminum housing are the only things in the front end I HAVEN'T broken.

If you skip the front locker or keep the tires around 32-33" I think you'll have far less in the way of problems. I haven't heard Alek or Greg mention any problems. Jon A has the same locker I do, but on stick gearing and 32" tires, and I think he's done fine. I pounded on the truck with the locker/gears and 265-70/17s and never broke anything. 35s started my breakage cycle.

[MK-voy]

so ur advice is to stick with 33 to be safe from heavy breakage??

[fishsticks]

so ur advice is to stick with 33 to be safe from heavy breakage??

Or leave the front open.

[v7guy]

Donny, nobody had actually grenaded the front diff have they? hasn't it mostly been failures of the disconnect?

I don't think there's been a strong reason to upgrade the diff yet... I don't suppose there will be a reason until someone makes a drop bracket for the front in an attempt to stay IFS with a chevycrew sized rig

[fishsticks]

Donny, nobody had actually grenaded the front diff have they? hasn't it mostly been failures of the disconnect?

I don't think there's been a strong reason to upgrade the diff yet... I don't suppose there will be a reason until someone makes a drop bracket for the front in an attempt to stay IFS with a chevycrew sized rig

Front diff failures have been exclusively due to neglect as far as I have seen. I'm sure one could destroy one with some stupidity, but I've been rough on mine, and the last fluid change was clean as a whistle.

That said, having a locker replaces the weakest link in those diffs: the spider gears. Those things are retardedly small.

[Skindiggers]

Guys.. i think our biggest problem is with the front axles , not the diff itself if we could find some stronger , bigger cv joints that can also have more angle of movement , than we will be able to run 35" tires without so many problems, we will also be able to lift the truck more and we will have more flex !

[v7guy]

The only option we have for CV upgrades are custom shafts from RCV and those aren't exactly cheap.
Then after that we still have to contend with the amazing exploding splined disconnect.

If I remember right the reason we became interested in the H3 diff originally was because ARB makes an air locker for them

[Skindiggers]

Do you have a link for those custom cv joints ?

[v7guy]

http://www.rcvperformance.com/store/catalog/index.php

https://www.rcvperformance.com/store/catalog/product_info.php?products_id=121&osCsid=e2612bed961488215fae133f921e1a1b