Maintenance: G-body front bearing hub replacement

[robaurora01]

im surprised this is not a sticky!

[Aurora40]

Nov 9, 2008 7:05:04 GMT -6 robaurora01 said:

im surprised this is not a sticky!

It is stickied here:
aurorah.proboards47.com/index.cgi?board=nextgeneration&action=display&thread=5422

Otherwise we'd have about 50 stickies at the top of the board.

[robaurora01]

ohhhh, well that makes more sense now lol

[tfmooney]

kudos to kobalt for these great instructions. They gave me the confidence to DYI my 2001 3.5l. It took me about 140 minutes to change my left front bearing hub and I took my time to make sure everything was clean and free of corrosion.
My experience was a little different. No problem with a tight splined drive shaft but corrosion inside the knuckle wouldn't let the hub release from the knuckle. I had to pry out the hub. When I did, the wheel speed sensor portion separated from the hub and remained inside the knuckle. I had to pry it our with a screwdriver. Everything else went very smooth.
Thanks again.

[ntrenn]

Another encouraged to do their own work!!!!

I had the same problem with the bearing separating on my Rendezvous, but it took me 2 hours with a sledge to get all the pieces out....

[oldwino]

There's a trick that machinery mechanics use that may help in some cases when the old hub is stuck in the knuckle.

When putting press fit bearings on the shaft, they would cool the shaft, causing it to shrink, and heat the bearings, causing them to expand. Then the bearing is put on the shaft and once the temps equalize you can't even beat the bearing off if you wanted to.

i realize that the hub is already in contact with the knuckle, but heating the knuckle while using some ice in the center of the hub may help in getting some clearance to remove it.

Just a thought.

[clutch1]

To break the axel shaft free from the hub I'm a big fan of using a punch right in the hole in the middle and smacking it with a big hammer till its free. Everyone has their own way though lol.

Nice writeup though, always good to encourage people to DIY, that's what I always tell people (prolly won't once I work at a shop and all, but for now it's no loss to me )

[aweb80]

Thanks for the write up. I need to do this to the passenger side soon.

[luxman]

Ok, so i did replace my left front bearing this morning.
Mine is a 96 and there are some differences the way the bearing is bolted to the knuckle.
First instead of having three 13mm bolts in back of the knuckle, you will find 3 T50 (torx) in front of the bearing. You just have to go through the biggest hole in the hub.
Same thing for the caliper... Torx instead of bolts (T50).
No need for a puller with mine, shaft got out with the push of my hand (after removal of the 34mm for sure ;D).
Took me about 45 minutes to complete the job.

Really easy if you do have the right tools.

Oh! bonus! My traction control light is off now. ;D

Thanks for all those pictures!

[aweb80]

FYI, the 2 gen Aurora's (all G bodies for that fact) have the same front HUB as the Second gen W cars.

[schmoe]

Thanks for the great tutorial. Currently trying to do this myself.

Found a couple of difference between your car and my '96 Aurora. First my caliper bolts take a 3/8" hex (like an allen wrench), and my hub anchor bolts also take a hex from the front of the hub.

My current issue is with the hub anchor bolts. The top one seems stripped, the other two seem either a size in between my metric or english sets or super corroded to the point of not taking the right hex socket. Has anyone run into these problems victoriously?

[trey1475]

Thanks for posting... this will be my next project to tackle this weekend... The technician at Kaufman told me he couldn't do an alignment because my front bearings were bad.

[andy2003si]

What car is that?

[andy2003si]

May 2, 2009 11:03:48 GMT -6 clutch1 said:

To break the axel shaft free from the hub I'm a big fan of using a punch right in the hole in the middle and smacking it with a big hammer till its free. Everyone has their own way though lol.

Nice writeup though, always good to encourage people to DIY, that's what I always tell people (prolly won't once I work at a shop and all, but for now it's no loss to me )

I've seen my dad use this technique on my mazda mx6 lol, and he's a gm certified tech!

[trey1475]

I have a 3.5 2001. We did it this past Saturday and it wasn't too difficult. I didnt need a puller to get the hub off.. I did the trick that Foxman suggested earlier in this thread and it came right off. Thanks for the help.

[bobsblue95]

@schmoe... those three bolts holding the hub on are *not* hex/allen head bolts, they are TORX, T-55. Also an easy way to stop the axle spinning without the rotors installed is to simply back out one of those bolts and stop halfway through the access hole, then remove the axle nut. A gentle tap on the hub with a brass mallet was all it took to get my hubs loose from the axles.

[RCA1186]

Did this today, was pretty straight forward, I didn't even need a puller for the hub, about 5 wacks with the sledge took it off with ease haha, the problem I had was with the hub bolts, they felt like they were welded in, one head got rounded and I broke a wrench on another of the bolts!

By the way, the hub bolt is a dealer item at $4.37 a pop.

[RCA1186]

By the way "maintenance" is spelled wrong on the thread title

[RCA1186]

Also per the FSM caliper bolt torque spec is 38ft/lb not 130ft/lb, drive axle nut is 107ft/lb not 120ft/lb

[nelson480]

Good to know about the axle nut. RetardZone said it was 100 lol

[RCA1186]

Well I'm not sure how much a difference 7ft/lb would make lol, but still, I don't trust them for most things haha. Oh by the way, Dorman wheel studs have the wrong part number listed for Aurora's studs at every major parts store in America meaning good luck finding the right size one if you need it lol

[Aurora40]

Oct 14, 2011 22:48:07 GMT -6 RCA1186 said:

Also per the FSM caliper bolt torque spec is 38ft/lb not 130ft/lb, drive axle nut is 107ft/lb not 120ft/lb

I have to think you are reading that wrong. Caliper mounting bracket is usually quite high. Make sure you aren't confusing it with the sliding pin that holds the caliper to the bracket. To do a hub, you'd remove the caliper bracket from the knuckle.

My FSM says 137 lbs-ft front, 91 lbs-ft rear. And just generally in my experience, caliper to knuckle torque is usually pretty high, high enough it's hard to do in the confines of the wheel well.

[RCA1186]

Oct 16, 2011 10:08:56 GMT -6 Aurora40 said:

I have to think you are reading that wrong. Caliper mounting bracket is usually quite high. Make sure you aren't confusing it with the sliding pin that holds the caliper to the bracket. To do a hub, you'd remove the caliper bracket from the knuckle.

My FSM says 137 lbs-ft front, 91 lbs-ft rear. And just generally in my experience, caliper to knuckle torque is usually pretty high, high enough it's hard to do in the confines of the wheel well.

Nope

[Randy T.]

Brake bracket to strut- I think this should say brake bracket to knuckle.

Brake caliper to knuckle-This should say caliper to bracket.

I checked my '98 and '97 fsms and they both said the same as your picture. But, as Aurora40 said, caliper bracket bolts should be torqued to at least 100ft lbs or more. That info is a mistake. I hope people are not torquing their caliper bracket 13 lbs, that's a scary thought. lol

[XJSman89]

I guess I never posted in this thread. This writeup helped a ton last summer; it made my hub replacement really easy! After my brakes locked up and my ABS and Traction Off lights illuminated I got the car scanned at a dealer and was told the speed sensor in my right front hub was bad. I got it replaced in no time with this writeup at a fraction of what the dealer wanted to charge!

My hub wanted to be stuck in there too, after hitting the upright with a torch for a little bit it popped right out with some elbow grease. Good stuff!

[RCA1186]

Oct 25, 2011 11:53:48 GMT -6 Randy T. said:

Brake bracket to strut- I think this should say brake bracket to knuckle.

Brake caliper to knuckle-This should say caliper to bracket.

I checked my '98 and '97 fsms and they both said the same as your picture. But, as Aurora40 said, caliper bracket bolts should be torqued to at least 100ft lbs or more. That info is a mistake. I hope people are not torquing their caliper bracket 13 lbs, that's a scary thought. lol

My brother's Chrysler manual lists his at 15ft/lbs

[sempar]

Excellent write up. I've helped my son do front hubs ( three times) on his 2004 Alero. Never had to replace the hubs on my 89 Olds 98 ( 350,000Km and counting).
My 2001 Aurora FSM shows 137 ft/lbs for caliper to strut mounting bolts. Wouldn't be the first time I've seen printing mistakes in manuals.

John

[armond21]

First off, thank you all for a fantastic forum. I own a 98 non autobahn edition and this has been an excellent source of information.

As of right now, I'm planning on purchasing all new wheel hubs, calipers, brackets, rotors and pads in the front and rear. The issue i'm having is I'd like to replace the hub bolts also (I live in northeast Ohio and we love our road salt) since they're probably rusted. I'm unable to locate the part numbers on the GM parts sites. Can anyone point me in the right direction? I think I may have located the front ones on gm parts direct labeled as "Splash shield bolt" but I'm not sure that's even correct.

Thanks guys!

[sall]

Front... Number 7. That part number 1802 2052.



Rear... Number 40. That part number is 2561 0656.

[armond21]

Thanks for the speedy reply! It has occurred to me that I've forgotten about the caliper bracket bolts. Could you possibly identify the part numbers on #16 in the first image, and #44 on the second? I'm assuming those are the bracket bolts. Much appreciated! The first few rounds are on me if you're ever in my neck of the woods.