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02 Bravada Smart Track Front End Problem, PLEASE HELP

01-13-2009, 05:34 PM

I have a 02 Olds Bravada with the AWD Smart Track system. Recently while coming off the highway I noticed a couple crunches and a Thud in the front passenger side Wheel. After further looking into the problem when I got back home, I noticed the front CV Joint was hanging there not pushed into the front differential.

So I took the wheel off, popped the Ball Joints off, Tie Rod end and loosened the Axle Nut and pulled the axle out. What I thought was first a busted CV Joint, I noticed some extra parts coming out with it. After everything was out of the way, I noticed on the front differential I could see the output shaft.

So come to find out after doing a bit of research I found out that it was part of the housing on the differential that had busted. GM doesnt have a name for it but "housing". It is a housing on the housing of the differential. Or like a housing for the output shaft that the CV joint when put all together butts up to. Then I googled the OE part number and found a website that has a brochure of different differentials/parts and found they call it a "Disconnect Housing". After attempting to locate this part ANYWHERE on the internet and every parts store in the State of Indiana, I have found myself here. To my surprise every forum I have searched I have failed in finding someone else anywhere that has had this problem. It has rendered the vehicle useless.

So I am here just to see if anyone here has had a similar problem and can help me identify the correct part. Im almost 100% that I have it identified from the AAM brochure using the OE Part number to CTRL+F to find it.

GM wants $300.00 for the part and would like to save a bit of money fixing this. They frustrate me cause even their mechanics had never seen anything like it before.

If anyone could please maybe speak from experience or look into it for me I would greatly appreciate it.

The OE Part numbers I did manage to get from GM is.....

"Housing" #12479197
Bearing #26063326
Seal #12479302

What I got from from the brochure is.....
Disconnect Housing #74074107
Bearing #74003326
Seal # 7400434P

I did contact AAM through email and asked how to buy from them and they just told me that I have to contact a Distributor to locate the part. I did call a few earlier but everyone is telling me that what they carry is the actual Differentials, Ring, pinion, Shafts, housing all sold together and not sold seperate. I offered the AAM part number and they said there wasnt anyway for them to cross reference and find it for me. I felt like they just didnt want to mess with it. ( is the url for the AAM brochure, in PDF form. You will have to CTRL+F and search for the part number, either part number to find it.

If someone could please tell me that I have the right part also carries one. My faith in GM is.....ya.....I dont have words to finish that sentence.

But anyway, I can't seem to get a 100% professional confirmation that I know what I'm talking about. :banghead: :banghead: :banghead: :banghead: :banghead: :banghead: :banghead:
Any and all help will be greatly appreciated.


Chris Stewart
01-15-2009, 06:52 AM
What do you think about using a complete front differential out of a junkyard Bravada, Blazer or Jimmy KC?
I don't know for sure about the '02 differentials but the '97's have the ratio stamped on the passenger side tube/front side of the rear differential. If you find your ratio and find the same one at an automotive recycler, you might get what you're looking for.
For your Bravada to just start dropping front differential parts is new to me. Is it possible it was involved in a wreck or some other event the did severe damage? By replacing the whole differential assembly, you might be removing any other damaged pieces that haven't finished breaking apart yet.

01-15-2009, 07:48 AM
I have seen this before, when the Bravada first came out I was a SM for Oldsmobile and some guy went on the beach and busted up the ft diff. The 2002 if it is like my Trailblazer goes thru the oil pan. Anyway, I would be concerned as to why this happend before just fixing it, make sure the diff didn't break up forcing the housing the also come apart. This is an oe part only from what I can see. Remove the diff drain plug and see what comes out with the fluid.

01-15-2009, 08:14 AM
Yes, the Trailblazer, Envoy, and Bravada all use the same AWD 02-09. I know there is a variation that sometimes make these different, but I know GM told me that these vehicles still come out with this AWD system. When Identifying this part, I went to a new dealership and climbed underneath a few Trailblazers and Envoys just to see how this was together, I will put a picture of this broken part up either as my signature or somewhere else and include a link. What surprises me the most, with all these same vehicles having the same suspension, that they still use this and I'm having trouble finding that part.

I was thinking at some point in time that it was damaged, or ran into a ditch or something...hit a hole large enough to tweak the entire suspension on that entire side, I should of also included that the CV joint's band was also popped off and all the grease in the joint was slung all through the wheel well.

I have called a few junkyards that keep newer vehicles and what I have been told is that once these housings are installed and drove on for 50k or more miles they have a tendency of breaking or cracking right at the recieving end for the drive axle. Anyone who has a trailblazer, envoy, or bravada can look at their vehicle on the passenger side. Right where the Drive Axle goes into the front differential theres a Cone or cylinder Shaped aluminum piece that recieves the drive axle. You can see this without jacking the car up, that Cone or Cylinder shaped receiver is what broke, that is part of the housing, at least what GM calls a is odd shaped and I've never seen anything like it. I have a picture of it, I will upload it as my sig or something today....Im just wondering if you guys are right and more damage has happened during this process. It is about 5 below outside right now and supposed to be colder tomorrow, I will pull that drain plug and see what comes out....may take a day or 2, its horrible cold here in the midwest.

Thanks again, you guys are great.

01-15-2009, 09:30 AM
11 below here in upstate NY, this AM. I will look at my TB, it has 110k and has had plenty of 4wd use, sure sounds like the deal with axle points to some external forces are in play here. I would look real close at the suspension and chassis for anything suspicious, how long have you owned this truck?

01-15-2009, 10:04 AM
What sucks, I just bought this in August....So its really new to me still. I bought it used from one of those County Fair Tent Sales. I did take it to the mechanic before I bought it to have it looked over real good. Guess he missed

But I talked to another mechanic today, he said his shop calls that part an Axle Tube, I ran the Disconnect Housing name across him he said he'd never heard of that before.

I do wish I would of ran a Carfax on this vehicle before I bought it, Im starting to wonder if it wasnt wrecked at some point in time. Or ran into a ditch or something to cause some type of evil tweaking on the front in.

I have some pictures on my cell phone that I can bluetooth to my computer, I can show you guys exactly what I am talking about. I will have them up after I pick up the wife from work, so probably around 3pm EST. I will probably load them up to my Myspace that way they will be full size and can see detail. Ill post back in a bit.

Good thing I am laid off from work for a if this would of happened next month Id been taxing it to work 15 miles each way..:banghead:

01-16-2009, 05:54 PM
Man, its been so cold out today..... What did ya guys think about that plane landing in the hudson? Pretty crazy stuff.

Anyway, I finally got the pictures posted to my myspace account. I put them there because they are larger and more detail can be seen. Just so you get more of an idea of what I am talking about.

This is the direct URL to my
myspace, ( View pictures and they are under their own Album, about 5 or 6 of them. I left captions with the pictures to kinda tell you how stuff goes together.

Did you ever look at your TB Chris? You can see this part barely from the front passenger side, the drivers looks nothing like the passenger.

Well we went ahead and had GM order the part without paying for it, that way we can see exactly what we are working with...Didn't think of that before, but I would still like to find a Distributor for AAM or a way to buy this part cheaper than what GM wants for it, 277.00 just for the housing, not sure on the bearing and seal yet...

Still not 100% we ordered the right part. lol Well I appreciate your help and time, if anything someone else will at least have this forum and I will leave them pictures on my myspace so anyone that ever googles and tries to find information or has this problem they they will find information for it.

My father-in-law today, googled about this part for me and came up with this site. After he read it all and was thinking "hey this guy has had the same problem" he realized it was me. lol

Thanks again AF, Max and Chris for helping out. You guys are the best, definately my new site to seek out help!!!!!


01-25-2009, 01:10 AM

any follow up on this yet? my '02 bravada has been making noise on the front passenger side, take it in to the shop and they tell me nothing's wrong. i don't want to end up hearing a "crunch and thud" like you did.


01-25-2009, 03:13 PM
Yes, have you checked out the pics I posted on my myspace? It turned out to be what is called a Disconnect Bearing. Its really hard to say that you are experiencing this same problem, but I would definately be worth looking into. Where you CV Joint meets your front differential, if you look at the pics you can see the part that broke on mine.

That part broke from the housing, it was all one piece. I'd say mine came from the previous owners either wrecking it or hitting a hole or ditch hard enough to crack that piece. It can be started as a crack that even a mechanic unless he is looking for it could easily over look. If at all possible jack your car up, put it on jack stands (for safety) and climb underneath your car. Look for the housing and make sure you don't have a crack in it. If this part fails your 4 wheel drive will not work at all and could end up having your CV joint pop out of the front end and causing more damage than you want.

I would also say, maybe its in your Hub rather than up in the differential, but would definately be worth looking at your to make sure you arent hearing the early affects of what happened to mine. The pictures can be seen under "Pics" at

Post back and tell me what you end up finding out. I finally have the part coming in Tuesday so mine will be fixed.
over 300 dollars for this fix, it isnt cheap and even if your is cracked it would just be a matter of time that it would fail.

Chris Stewart
01-26-2009, 05:37 AM
Good pics Kevin.
You might make sure there's no junk inside the front differential before you reassemble. Is there a front differential cover you can remove and wash out & check the innerds?
Maybe the replacement part will be a stouter piece.

01-26-2009, 12:41 PM
O ya, I am definately going to clean out as much as I can. The output shaft where this housing bolted to, was packed full of some heavy duty Grease and where the part had beat around it was also filled with Aluminum shavings.

I am going to pull the plug for the differential and drain it to make sure there isn't more that happened to it. I'm pretty sure it's safe to say its outer workings rather than inner, but I am going to be 100% before I get it all back together and back on the road.

Another question I have been meaning to ask, I havent really had to the time to go look myself, is there an actual plug to drain the front differential, I mean these front ends are different and are like built through the front oil pan. I really dont know too much about these, but if you know or anyone knows the "Easy Way" to drain them please share that info. :iceslolan

Chris Stewart
01-27-2009, 06:12 AM
All my front differentials through the years did/do not have drain plugs.
Remove all the cover bolts except a top bolt and a bottom bolt...just back them out about 3/8" then set your drain pan and pry the bottom of the cover outward to drain until the big gush subsides then you can remove the last bolts and cover.

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