Ive seen it referd to as  the batwing. The crossmember that the differential bolts to and the ends have bushings that rest/bolts to frame. How are these bushings removed from the crossmember? I want to replace with new. By the way its a 78. Thanks.

          We used some wd-40 for lub. Made a double wedge, much like a pickel fork. You can hammer it or weld shaft from a muffler chisel and use a burp gun. Come out fairly easily, leave bolts in to catch.

I burned the last set out with a torch I did..but the air hammer would work fine also..I had more trouble separating the bushings from the frame..it's like they were welded on there..but it popped off ok..to do it at home would take some time..maybe a big hammer and chisel and work your way around until it pops loose..if you don't have the patience for that then most shops can get them out without much fuss.. Rich

I used a hydraulic press to push them. After cleaning and painting, I then soaped up the new ones and pressed the new ones in.

'78 would NOT have a "batwing" style diff mount. It will have a "normal", steel crossmember. The bushings in those are held in by tabs that are bent over onto the crossmember. Bend the tabs back straight, soak the outer edge with penetrant(WD40, PB Blaster, etc), and you should be able to smack them out with a hammer(manual or air powered), or press them out with a press.

The '80-'82 diffs with the "batwing" mount are a bit more difficult, and may require some heat. There are tools available to remove/replace them but they can be removed without.


http://www.c3vr.com/member_pages/4401_4500/4427/diff1.JPG

Joel I was wondering about the batwing term. I didn't realize that when GM went with Dana that the batwing term came into play. Also I forgot about the fun of the tabs in the removal and installation process. I bent them over somewhat on the new install, then used the press to totally bend them back. You always keep the information coming.........thanks!  

Thanks for the replys. I had no trouble removing crossmember from frame.(lucky I guess,the car sat for more than 15 yrs. Only 57k on od.) OK,. so bend up all the tabs,soak with penatrating oil and press them out. Looks like a steel sleeve around bushing, is that part of crossmember or bushing? Sorry for all the questions but this is my 1st vette and dont want to screw anything up. I saw the term "bat wing" in another post but didnt see any simularety. Great info on this site, Thanks again.

Frank, the steel is wrapped around the crossmember cushion.  It will push out. Just throw the old stuff away. When you get the new crossmember cushion, they will have the steel wrapped around the new rubber

|UPDATED|10/13/2011 7:35:25 AM (AZT)|/UPDATED|

Frank on the bottom side I added this...........I would recommend it...............

|UPDATED|10/13/2011 7:38:28 AM (AZT)|/UPDATED|

Ask any and all questions you may have...we're here to help!   Everyone here learned by doing, and from having someone's help. It's a lot easier to work on/repair/restore one of these gems when you know you have someone that has already been there helping with info.