68 Differential Crossmember stuck
Thread Starter
Melting Slicks
Joined: Jan 2006
Posts: 3,028
Likes: 2
From: North NJ
68 Differential Crossmember stuck
I removed my half-shafts (68 is considerably thinner than later years), rear struts, original 9 leaf metal spring, aftermarket air shocks, drive shaft and differential. I've read that you should losen the diff crossmember but not take the bolts out, remove all other bolts holding diff to anything and use the weight of the diff case to pull down on the crossmember bushings. I used pickle forkes to try to "pop" the bushings and get the crossmember down but with no result. I beat the crap out of those pickle forks trying to pop the crossmember bushings. What am i doing wrong? Finally I just unbolted the diff and pulled it off the car. (bubba already cut two holes in the inside body to access the 4 diff bolts to crossmemeber. Any ideas of how to get the crossmemeber down? I'd like to paint it with POR-15. Are these bushings replaceable? I'm ordering the performance plus suspension kit from VB&P and I beleive they are included. Are these difficult to replace? The ones on the car are original along with everything else so I'd like to replace and paint. Any ideas guys?
Melting Slicks
Joined: Oct 2004
Posts: 2,662
Likes: 8
From: Knoxville Tennessee
The diff crossmember bushings are just rubber over a big round stud. It is a tight fit but there isn't anything holding it except the pressure of the bushing itself. Use a big pry par on each side and it will come down, and if it is that tight I doubt that it needs replacing. It doesn't do anything except keep that joint tight and not squeek.
Bernie
Bernie
Intermediate
Joined: Mar 2006
Posts: 32
Likes: 0
From: Wallingford CT
Rear Crossmember Removal Help
Here's are some tipsto help remove a stubborn crossmember. Use the weight of the differential with a tranny jack or other support about an in or so just below to catch it from falling. Hit the stubborn atttaching areas with PB Blaster or you favorite penetrating oil for several days before the disassembly party. Loosen the bolts holding the crossmember in place, but leave them in somewhat to catch the diff and crossmember. Use a pry bar as described in earlier posts. If necessary, add a LITTLE heat to the bushing bolt with a propane torch (1-2 minutes or so but, be careful not to heat it too much. Use the 3 foot pry bar again if necessary. Say a prayer or two before, during, and after. 
Instructor
Joined: Jan 2006
Posts: 166
Likes: 23
From: Colorado Springs Colorado
Use a 2-jaw gear puller. Thread the bolts in 3-4 turns to prevent it from hitting the ground when it pops loose. Put the 2 x jaws on the outside part of the crossmember, put the gear puller bolt on the bolt going up into the cross member and tighten. It will pop right out in a matter of seconds. I fussed for over an hour with a crow bar and didn't get very far. The gear puller works just like a machine press. I've heard it also works great on the strut mounting bolts as well.
I never liked the crowbar because of how it made the car rock when it was on the jack stands. Didn't feel too safe to me. I didn't need any heat or anything.
RE: the crossmember bushings. I think you'll find you're cross member bushings will be in pretty decent condition once you remove the crossmember, despite how badly rusted your actual crossmember might look, the bushings seem to hold up well.
If not, Zip and Ecklers both sell replacement bushings. I took mine to a local machine shop to have them pressed out, and the new ones pressed in.
I never liked the crowbar because of how it made the car rock when it was on the jack stands. Didn't feel too safe to me. I didn't need any heat or anything.
RE: the crossmember bushings. I think you'll find you're cross member bushings will be in pretty decent condition once you remove the crossmember, despite how badly rusted your actual crossmember might look, the bushings seem to hold up well.
If not, Zip and Ecklers both sell replacement bushings. I took mine to a local machine shop to have them pressed out, and the new ones pressed in.
Pro
Joined: Apr 2005
Posts: 603
Likes: 2
From: Illinois, USA
The gear puller worked better than anything I had to work with up to that point, except that it kept pitching to one side or the other ...so that was a little frustrating.
I ended up shooting some PB Blaster on it, and dropping it down, and rocking it back and forth to get it to come free (twist towards front and rear of the vehicle). I had one that came loose, and the other was being a pistola.
Brian.
I ended up shooting some PB Blaster on it, and dropping it down, and rocking it back and forth to get it to come free (twist towards front and rear of the vehicle). I had one that came loose, and the other was being a pistola.
Brian.
Team Owner
Joined: Jul 2004
Posts: 40,412
Likes: 792
From: Redondo Beach, California
Even though my 68 was rust free and the trailing arms/shock mounts, etc,were easy to remove, the differential crossmember was not. I had to use a crow bar. OK now that the crossmember was out, I decided to replace the rubber bushings. I took a grinder and removed the bent over 'tangs" that held the old bushings in. After grinding these things away, I just knocked the old bushings out.
I sealed up all the openings on the differential crossmember with duct tape and then poured about a quart of Rustoleum Primer into the interior of the corssmember. Swirled it around, and poured out the paint. I also drilled two small drain holes into the differential crossmember. The differential crossmember can collect water, so some drain holes are a good thing.
To install new bushings, I took them to a suspension shop and had them pressed into position. (Actually this was Tom's Differentials. They were nearby, although I think they have now moved to Idaho.) I think you need a press to get the new bushings installed.
I sealed up all the openings on the differential crossmember with duct tape and then poured about a quart of Rustoleum Primer into the interior of the corssmember. Swirled it around, and poured out the paint. I also drilled two small drain holes into the differential crossmember. The differential crossmember can collect water, so some drain holes are a good thing.
To install new bushings, I took them to a suspension shop and had them pressed into position. (Actually this was Tom's Differentials. They were nearby, although I think they have now moved to Idaho.) I think you need a press to get the new bushings installed.
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Thread Starter
Melting Slicks
Joined: Jan 2006
Posts: 3,028
Likes: 2
From: North NJ
Two jaw gear puller worked GREAT! Was using a crowbar but since the car is on jackstands I didn't like the way the car was shaking since the diff was already off. Shot some PB blaster in the bushing and used the gear puller and POP. Scared the crap out of me the first time, sounds like a gun. I have a press to put the bushings back in. What do you do if those bushing flanges break off when bending them upwards? Good idea with pouring the primer. If I've got some POR-15 left I'll give that a shot. With all the dismantling this weekend I now need to find a tranny shop in northern Jersey to check my muncie 4spd out. It seems there is a bit of play left in the shaft that connects to the flywheel. Don't know much about manual trans so I'd like to find someone good but reasonably priced. Its a matching trans so I don't want to get screwed. Any recommendations?
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
I feel the 2 jaw gear puller is the best choice but I do find that 2 large chissels really work great. Just leave the bolts 1/2 way in to catch the crossmember when it drops, insert on chissel in front between the frame and crossmember and another behind. By hitting back and forth the chissels are driven in and will quicly pop the crossmember off.
