Driver's front cv issue…help!

[jandhsanchez]

So I'm new to Envoys/Trailblazers. I just got a 2004 Envoy SLT last week and for the most part I love it. It's great for the family. I have 4 kids and the leather, nice interior, ac, and smooth ride are all perks compared to my last ride. I had a 1992 Landcruiser with 3.5" OME lift with 35" BFG Krawlers. It was great off-road but I needed a more family friendly vehicle and wanted one with some attitude and off-road capability. I stumbled across an Envoy with what seems to be the Liftmeister 2.5" spacers up front and I'm assuming Z71 springs in the rear (or other lift springs) because there are no spacers in the rear and the rear is slightly higher. It also has new sway bar links all the way around. New shocks and struts as well. It's a nice ride for sure and I'm looking forward to making my own and getting a body lift, 33s, roof rack, lights, etc. but I ran into a potential problem this week. It looks like the cv axles are new up front as well with new rotors and pads all the way around. The drivers side cv is making a ton of noise at the diff and there's quite a bit of play as well. When driving it squeaks and clunks and binds while moving at any speed, but more noticeable at slow speeds. When trying to turn the tire while jacked up it moves backward with resistance. It won't roll forward at all while jacked up. On the passenger side, the wheel will go freely in both directions, forward and backward. The videos attached show this. I've searched all over this forum and trailvoy for answers but don't see anything like what I've got going on. There is no tear in the boot, no obvious signs of grease or leaking anywhere. My questions is

Is this just a cv axle issue or is it a differential issue?
Can I still drive it? It's my daily driver but if it will cause more damage or damage to the diff then I'll have to get to it sooner.
What is the fix? And how difficult?
What costs am I looking at?

I can do the work on the cv or potential bearing that I can get to without pulling the diff but if I have to pull the diff then I don't think I'm qualified to do it in my driveway.

My previous truck (FJ80) had solid axles up front with birfield joints. So no where near as much moving parts and relatively simple repairs. Just bearings and seals. I don't understand too much about the IFS these things have. Thanks in advance for the help.

Driver side



Passenger side

[Opeth]

Yea, with that much play... I'm going to guess who whole front diff is toasted. Those cv shafts shouldn't have more that maybe 1/8th play movement, less is better. I'm guessing your diff went dry and burnt all the bearings up. Pull the driver side fill/ drain caps and see what comes out... I'd bet metal shavings. Your looking at a whole new diff...

[jandhsanchez]

Thanks for the reply. I just pulled the front diff fill plug and it was bone dry. The former owner must have done no regular maintenance…only did the fun stuff. Thanks guy. Now to find a new diff and install. Oh man this will suck

[navigator]

if you have to replace the front diff and want to go to 33's, I would think strongly about looking for a front diff with 4.10s and a matching 8.6" rear diff with 4.10s, that is unless you are running 3.73s or lower now. Replacing the front diff is a ton of work (relatively speaking) and if you can upgrade at the same time you're ahead of the game.

Most of the TBs seem to have 3.42s and those coupled with 33's can lead to tranny overheating and a shorter lifespan.

[jandhsanchez]

Mine has the gt4 so 3.73. I would like to do that if i have the funds. doing the front is going to cost 500+ when its all said and done.

[jandhsanchez]

Also, now that I have to remove the front diff, (1) what other things will I need to replace at the time? What seals and bearings, and should I get new cv axles (because of the grinding I have)?; (2) Is there currently a locker produced for the front? If I'm in there and it's available, I may as well install it? Lastly, if I needed to drive it for a few days, would any more damage be done since the front is already shot? Thanks again for the info.

[KingBird]

There was a locker made.

Lock-rite made it for our 7.2" diff.

It has since been discontinued, and no one has one in stock. In that area, you're kinda screwed unless you just happen to find someone selling one.

I have an idea in that regard, but it's not something I'd do to a truck that would be primarily on pavement.

I recently had to replace my engine, and having removed and replaced the differential twice prior, removing the engine made working on the front diff extremely easy, lol! I used two separate methods each of the times I worked on mine. The first, I disassembled the front diff inside the frame and ended up removing it in three pieces, the two case halves and the carrier. This meant reassembling the same way, months later it began leaking at a rate that required attention. The second time, I unbloted the motor mounts and lifted the engine with a cherry picker enough to literally squeeze the diff out/in. This WILL NOT WORK WITHOUT CUTTING PART OF YOUR ENGINE CRADLE! I DO NOT recommend this method.

I've heard of others removing the a/c compressor and dead pulley to remove the diff up through the engine bay but I've never tried it.

If you need 4.10s there is a Bravada in the parts yard here in Lubbock with them, also a Saab 9-7x with them. Let me know if you need them. The parts yard here doesn't care if all you bring with you is a socket set and a sawzall, just sayin'...

[navigator]

I pulled mine up through the front. I went ahead and replaced my water pump while I was in there and upgraded to the awd sleeve and put a grease zerk in the disconnect while I had everything apart. I followed one of the threads here and it was pretty straightforward. Some bolts are much easier to get to if you jack up the engine. I put a 2x8 on the oil pan to distribute the weight as others had done, and took it easy. I need to write it up, there were a few bits here and there that would have made it faster.

[jandhsanchez]

If I were to go ahead a update to 4.10 is it a bolt in with the 4.10 diff. What else needs to be done, besides the rear getting it too?

Kingbird, if I wanted the 4.10 from either of these vehicles how much would that run me?

[jandhsanchez]

Also have the g80 in the rear so how difficult to install 4.10 there?

[KingBird]

I'll call and ask, not sure about shipping, a few of these guys have shipped diffs before, maybe they could chime in with the approximate weight for accurate shipping calculations.

I have no problem going out there to snag one for you. If it were me, I'd replace both seals before I installed it, might have to order those (I always have).

EDIT: I called them, their price for the front diff is $305. Seems kinda high to me. I don't remember paying that much for mine. Hell, the entire transfer case with encoder motor was only $200. I don't understand their pricing system.

[KingBird]

Well, I don't think it would be cheaper to ship an entire rear end to you, so you'll probably need to find that locally, or you could have someone change your gears out. It would be cheaper to find a junked envoy/Trailblazer/Bravada/Ranier
/ascender/9-7x in your area with those gears and just swap the entire rear-end.

[jandhsanchez]

Will the rear diff with the 4.10 fit into the 8" rear? And what about the current G80? Could that go into the new diff so I would still have it? Thanks for the info, just trying to figure this all out before I do it. I know I can just get a 3.73 front diff and put it in, but if upgrading to 4.10 is not that much more then I'll just look into that. Thanks

[jandhsanchez]

Thanks for the help Kingbird

[KingBird]

I haven't had gear work done to one of these rear-ends. I had 3.55 limited slip with HD gears put into my old 'vette for about $600. Not sure what it would run with a locker. It's usually cheaper to buy the entire rear and just swap it with your own.

Most Bravadas and Raniers from '02-'04 had 3.73s base, the rest had 4.10s and I haven't found one yet (awd) that didn't have the G80 locker. That's why I say to look for those in the parts yards. They were usually the "higher-end" versions of these trucks option-wise so you'll get more goodies out of them.

[navigator]

The 8.6 (from an 06) rear I have in mine was supposedly out of a Bravada and it has the G86 limited slip.

[KingBird]

Bravadas were discontinued in '04.

No clue about post '04, as the only Ranier I've found at the yard that was an '06 was 2wd, is now sans-motor (thanks to me), and I didn't even look in the glovebox to check for G80 or G86.

[navigator]

OK,maybe it was something else, it was one of the "off" brand gm step children, not the TB or Envoy.

[KingBird]

Their biggest mistake was making all of the step-kids awd instead of selectable.

How are you going to offer up luxury versions with no option of a low-range???

Don't even get me started on the Bravada front grill. Ugliest damn front-end since Edsel... I'd change it to the 9-7x front end if the headlights didn't throw like they do. Brightest stock headlights I've ever seen.

[jandhsanchez]

Well after a bit more research on some parts in my area I found a front carrier assembly with 3.73 for $220 about 5 min from me. So with funds the way they are I guess 4.10 will be added to the ever growing list of future mods. Thanks for the input.