Lowering Differential: What Am I Missing?
Thread Starter
2nd Gear
Joined: May 2011
Posts: 2
Likes: 0
Lowering Differential: What Am I Missing?
I'm installing one of the rear suspension upgrade systems by VBP on my '77 C3. I need to lower the differential so that I can remove the cross member. My problem is that the differential isn't coming down and I can't figure out why. I must be missing something.
Here's what I've done to this point:
1. Removed original leaf spring.
2. Removed shocks.
3. Removed struts.
4. Removed 2 bolts in differential cross member.
As I see in the VBP video, the differential should simply come down at this point. But it doesn't. The cross member is solidly in place and won't budge (even with encouragement from a crowbar).
Anyone have any ideas?
Here's what I've done to this point:
1. Removed original leaf spring.
2. Removed shocks.
3. Removed struts.
4. Removed 2 bolts in differential cross member.
As I see in the VBP video, the differential should simply come down at this point. But it doesn't. The cross member is solidly in place and won't budge (even with encouragement from a crowbar).
Anyone have any ideas?
Drifting
Joined: Jul 2004
Posts: 1,695
Likes: 65
From: Kissimmee fl
Finalist 2021 C3 of the Year - Modified
2017 C3 of Year Finalist
Cruise-In VIII Veteran
St. Jude Donor '07
Most will say get a bigger crow bar. 
Make sure to keep the bolts in the crossmember or swap them with a couple longer ones till you get it to break free. This keep it from crashing. Some here have recommended a 2 jaw gear puller. When I pulled mine, I went with a wedge (ball joint pickle fork) to get things loose. When it comes loose you will know it! 
Make sure to keep the bolts in the crossmember or swap them with a couple longer ones till you get it to break free. This keep it from crashing. Some here have recommended a 2 jaw gear puller. When I pulled mine, I went with a wedge (ball joint pickle fork) to get things loose. When it comes loose you will know it!
Melting Slicks
Joined: Mar 2009
Posts: 3,126
Likes: 15
All above correct. Apply pressure with a wedge front and back on one side and wait. You are allowing rubber of crossmember mount to peel loose from the "sombrero" the metal that the mount is stuck to. Apply more pressure and wait agian. It will come off. mike...
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Joined: Nov 2006
Posts: 19,445
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From: Athens GA
St. Jude Donor '12-'13, '15- '16-'17-'18-'19, '21
Did this just yesterday on my 75.
LOTS of PB Blaster up around the rubber bushing where it meets the frame. Let it run down into the bushing and set for about 30 min.
Then use the biggest pry bar you can find. Mine was a 5 footer.
Blocks or braces just under it about 4-6" away (from the upper cross member, not the diff) will catch it.
BUT - remember to get the front bolt out of the snubber on the diff where it meets the frame in front of the diff.
Ask me how I know........
Good luck and be careful.
I crushed my left pinky getting the spring off. It slipped off the braces/cinder blocks and drove the ratchet into my hand and then into the pavement. Finger has 5 fractures in it. Luckily its my left hand and I am right handed.
Bman
