# Removing the bushings on top of the rear differential



## Orion88 (Apr 24, 2012)

I have just about given up on removing my old, hard, cracked bushings from my rear diff on my 1970 GTO. I've beaten and banged on them, heated them with a torch (thats how I got my front bushings out), hit them with an air hammer, and so far they haven't budged, but I have managed to mangle them enough that now I HAVE to get them out. Any tricks here?? I'm painting my frame/suspension tomorrow and would like to paint the diff as well but I need those bushings out first!!


----------



## ALKYGTO (Mar 29, 2010)

Take a 3/8" drill bit and drill all around the center in the rubber to get it out. Works like a charm. :cheers


----------



## Orion88 (Apr 24, 2012)

Great... of course my friend who needed to borrow my drill for a 'day' has still not given it back. I guess I better remind him tonight...


----------



## geeteeohguy (Feb 2, 2008)

......and after you drill out the rubber and drive the inner sleeve out, you can easily collapse the outer shell and drive it out. I've never had a problem with them using the right bit on my air hammer: a very thin, wide rounded blade that conforms to the outer shell of the bushing and lets me walk it out from under the lip. Easypeasy, Jaaaap-an-eesy. Any questions?


----------



## Orion88 (Apr 24, 2012)

I'm not sure what you mean. Are you talking about the bushings on the control arms or on the rear diff? These are the ones I'm referring to. I don't see anything that could collapse as it all seems to be pretty thick gauge steel.

Sent from AutoGuide.com Free App


----------



## geeteeohguy (Feb 2, 2008)

Yep. Those are the ones. The right air chisel bit and the right technique and its less than a 5 minute job. BTDT many times.


----------



## leeklm (Mar 11, 2012)

Here is another trick that helps... hold a 2lb or larger hammer on the backside of the ear while you smack the bushing. This helps the bushing absorb the impact, and provides a little support to avoid breaking the ear off the diff. I have not had this happen, but have heard of it...


----------



## 66goatframeoff (Nov 8, 2011)

Do you have an heat they fall out when you heat them up but if not agree drill out the rubber and collapse the outer case put some anti sieze on the new ones if you ever have to change them out plus the drive in a little easier.


----------



## Orion88 (Apr 24, 2012)

I got them out with a drill and an air hammer.

Sent from AutoGuide.com Free App


----------



## geeteeohguy (Feb 2, 2008)

Excellent. The trick is to get underneath that flanged lip, and walk the blade of the air hammer around the circumference while prying out. It takes a super thin but strong blade and it gets easier the more you do. I can't even fathom trying to smack them out with a regular hammer....I'd be afraid of breaking the casting. The 'shock' effect of the air chisel is what does it.


----------



## rickm (Feb 8, 2012)

there are also a few tricks to installing your new ones.


----------



## Orion88 (Apr 24, 2012)

Do tell!!!

Sent from AutoGuide.com Free App


----------



## Instg8ter (Sep 28, 2010)

put the new bushings in the freezer overnight and lube them up before you press them in.


----------



## Orion88 (Apr 24, 2012)

And I should replace those with OEM rubber, NOT polyurethane, correct?

Sent from AutoGuide.com Free App


----------



## ALKYGTO (Mar 29, 2010)

I would go urethane, they are more rigid and will help control wheelhop.


----------



## Orion88 (Apr 24, 2012)

I thought there was an issue with polyurethane bushings on the rear suspension binding when you corner.

Sent from AutoGuide.com Free App


----------



## geeteeohguy (Feb 2, 2008)

I've heard that, but I'm not sure why that would be. I do know that the Urethane bushings are kind of harsh on the street. Also, no need to put the bushings in the freezer overnight....an hour or so will do the trick. That, and use anti-sieze on them. I install them with a big socket that fits perfectly and a press, for the arms, and a hammer on the diff. The arms need to be supported internally so they don't collapse.


----------



## Orion88 (Apr 24, 2012)

I bought some aftermarket boxed and tubular rear control arms that already have poly bushings in them. I just thought I should keep the diff bushings rubber so there is some flex in cornering. Honestly I'm not really sure. I've heard a lot of people say that poly bushings in the rear will immediately make your car worthless in the turns, but I know AlkyGTO is running with them and I've seen videos of his car destroying some on-ramps!!


----------



## chuckha62 (Apr 5, 2010)

If it were mine, I would go poly in the rear and rubber in the front. Oh, wait... I did. 

Personally, I like the control of the poly in the rear and the ride doesn't seem to suffer at all. The front have rubber and I like the ride quality better.


----------



## ALKYGTO (Mar 29, 2010)

Orion88 said:


> I bought some aftermarket boxed and tubular rear control arms that already have poly bushings in them. I just thought I should keep the diff bushings rubber so there is some flex in cornering. Honestly I'm not really sure. I've heard a lot of people say that poly bushings in the rear will immediately make your car worthless in the turns, but I know AlkyGTO is running with them and I've seen videos of his car destroying some on-ramps!!


Did you get the braces that tie the upper and lower control arms together? They install in front of the rear crossmember and factory 4 speed cars came with a stamped steel pair. 

I believe BearGFR has some upper control arms that use spherical bushings to eliminate any binding. Maybe he'll chime in here.

Honestly I don't notice any ill effects on my car and it does handle the twisties pretty good for a big, fat overpowered car with a locked rear.


----------



## geeteeohguy (Feb 2, 2008)

Bear's car has adjustable arms and Heim joints, I think.


----------

