Car Rear Hub Install - How To

A quick summary of some of the things i've fixed on the 2005 Pontiac Grand Prix GTP in the past couple years:
The reason i needed to replace one of the rear hubs on my Pontiac Grand Prix was because of a mistake i made weeks before.  While replacing my rear struts for the second time i accidentally hit the plastic ABS sensor with the 3lb hammer.

fix abs sensor, strut, shock, brake, wheel bearing, hub

Here's the entire process of installing the new hub.  But continue reading for more in depth description and pictures.

Install Rear Hub - GM - Pontiac Grand Prix

The struts are held onto the car with a couple of big bolts.  And in order to set them in place i needed to use the big hammer.  On one of the swings i missed and hit the back of the hub.  For some cars it wouldn't be a big deal.  But on my car i have a plastic ABS sensor which measures the rotation of the wheel. 

So even though i didn't mess up the ABS break itself, just one of the 4 sensors, it still caused an ABS warning light to appear on the dashboard.  It's annoying that if just 1 part of the whole process is broken, the whole thing doesn't work.  That's like saying if the 'Q' button on the keyboard is stuck, the entire computer won't work.

A few years ago i replaced the front hubs/wheel bearings on the car, with the help of my friend Mike.  I bought the hubs from Rock Auto via Ebay.  This time i compared a few other sellers.  The first thing i did is use my favorite trick for auto parts, checked Advanced Auto Parts.  They are usually more expensive but online there are always coupon codes that you can use to get $10 or $20 off when you spend at least $50.  Next i checked Rock Auto for their price.  And the last place i checked was Ebay.  It turned out that the best deal i got, on a part that looked to be well made was from Detroit Axle via Ebay.  The part looked good, had the ABS sensor attached, was less expensive then the others, and it was from nearby Detroit. 
detroit axle, how to replace rear hub, wheel bearing, grand prix

It arrived in the mail a couple days later and i went about putting it on the car.  This was one of the first jobs that i also got to use my new tool cabinet.  It was nice not having to run up and down the stairs after tools i needed in the garage.  Here was everything set out that i thought i needed.
garage tools, shop, car fix, repair, brakes, replace, hub, wheel

The first step was to remove the tire, break caliper and disc.  Then i had to remove the 4 bolts which held the hub in place.  I sprayed WD-40 and Liquid Wrench over the 4 bolts and gave it time to try and soak into the threads.  Also i tried a trick that i learned from working on the motorcycle, tapping on the top of the bolt head.  Just adding small taps will help to try and loosen threads that had been fused together for almost a decade.
replace wheel bearing, rear hub, pontiac grand prix

To access the bolts there are 2 holes drilled into the hub.  This allows you to insert a socket wrench with an extension.  So i tried loosening the bolts with a socket wrench.  I had to put a metal pipe over the handle to give me a bit more leverage.  But i eventually got all 4 bolts loosened and removed.  However that did not mean that the hub could be removed.  It is still set firmly in place because the round hub was rusted/fused/corroded in place inside of the fitting.  I'm not exactly sure what the name of that part is, the swing arm or the knuckle. 
how to remove hub, rear hub, car, bolt, rusted

It took me about 20 minutes of hammering with a large hammer to remove the hub.  I hit it from every angle, hit it with a wood block, hit it while pulling on the front.  I eventually saw some movement from the swing arm, and a few minutes after that the hub was removed.  I could actually see the broken ABS sensor.
abs sensor, damaged sensor, hub, wheel bearing, gm

Before i put the new hub in, i decided that i should test to see if it will fix the problem.  So i connected the wire to the back of the new ABS sensor.  When i started the car the warning light went away and i knew that it would fix the problem.  To fit the new hub back in place i first needed to remove the corrosion.  So i used sandpaper and a wire brush.  Lots of white powder came down
replace hub, pontiac, rear end, install, fix, replace

while i was scraping.  Even after the sanding and scraping the hub didn't seat easily.  To get it to fully set in place i had to gradually tighten the 4 bolts down, sort of in the same way as you would tighten down lug nuts.  My goal was to get the hub to tighten flush with the swing arm socket.  If it wasn't straight, the wheel would be out of alignment.  But after i felt that the hub was tight, i reinstalled the disc and caliper.  Then rebolted on the wheel.  Everything seemed to be working fine.

Then a couple of things happened.  The first unrelated thing was that my front tire popped, not the tire on the rim i just replaced.  I had hit a pothole back in February and my tire rim was bent.  Because it was an aluminum rim there wasn't anything that anyone could do.  If it were a steel rim it could be bent back into place.  But the car still rode fine, for 6 months at least.

This is a picture of that same rim, when i hit a pot hole a couple of years ago.  Apparently in Michigan your right front tire (closest to the curb) takes a lot of abuse from pot holes.
dented aluminum rim, fix aluminum rim, flat tire, pothole

When i took the flat tire off i was surprised to see that it wasn't a puncture, but rather the top-inside edge of the wheel was worn completely down to the steel.  It was probably a combination of riding with a slightly flat tire and because of the dent in the rim.

I'll have to publish another post about finding a new rim and tire and rotating the tires.  But also i have to mention that i did need to take the car to get an alignment.  I looked into doing it myself but it was too complicated.  The fronts were ok but the rear tires needed some minor adjustment, probably from the two times i replaced my rear struts.  For now though, it's riding fine and will hopefully go last a while before something else going wrong.

1 comment:

Anonymous said...

I stumbled upon your blog the other day looking for some info on doing a rear hub install. It was a huge help! Thanks for posting images too!