Dropping my Diff
Thread Starter
Instructor
Joined: Sep 2008
Posts: 216
Likes: 0
From: Eugene OR
Dropping my Diff
Hello everybody,
I'm dropping the differential out of my '72 small block and I'm running into a very strange problem.
I dropped my spring, my control arms and bracket, disconnected my short shafts and driveshaft, put a jack under the diff and disconnected the the single bracket in the front and the two bolts that connect the crossmember to the frame.
For whatever reason, the diff doesn't drop.
Does anybody know what I've missed?
Thanks!
I'm dropping the differential out of my '72 small block and I'm running into a very strange problem.
I dropped my spring, my control arms and bracket, disconnected my short shafts and driveshaft, put a jack under the diff and disconnected the the single bracket in the front and the two bolts that connect the crossmember to the frame.
For whatever reason, the diff doesn't drop.
Does anybody know what I've missed?
Thanks!
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
Yes rust. The two bolts that hold the crossmember are stuck. The sombreros are rusted or stuck together. This is a common problem. Either use a long prybar, I have a 6 foot bar I use or use a gear puller. When it pops you will hear a loud bang. Have the rear supported as it weighs in about 100 pounds.
Le Mans Master
Joined: Oct 2000
Posts: 7,831
Likes: 5
From: Austin TX
Yeah, a really big pry bar!
You need to pry the crossmember down.
It takes a LOT of force.
Do some searching and you'll see lots of advice.
I bought a longer bar a few weeks ago to do some garden work which should work nicely next time I change a diff.
The last time I did one I almost hurt myself.
I must be getting old!
You need to pry the crossmember down.
It takes a LOT of force.
Do some searching and you'll see lots of advice.
I bought a longer bar a few weeks ago to do some garden work which should work nicely next time I change a diff.
The last time I did one I almost hurt myself.
I must be getting old!
Burning Brakes
Joined: Sep 2008
Posts: 805
Likes: 5
From: Naperville Illinois
My vote is for the 2-jaw puller. Put the 2 crossmember bolts back in about halfway; the puller will bear on the bolt heads and the bolts will keep the diff from falling to the floor when it comes loose.
Drifting
Joined: Jan 2011
Posts: 1,853
Likes: 81
From: Hamilton Virginia
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Team Owner
Joined: Mar 2002
Posts: 24,160
Likes: 78
Use a puller not a prybar
A prybar will force the joint off center which is why it takes so much force that way. A puller will yank it straight down.
Melting Slicks
Joined: Apr 2004
Posts: 2,008
Likes: 38
From: Space Coast Gator Territory
What I didn't see anyone mention is buying long shoulder bolts to replace the factory bolts, when prying the notoriously stuck sombreros loose. These long shoulder bolts will stop the assembly from falling to the ground, as mentioned. They also help in the reassembly, by guiding the cross member up into position. Remember, the weight of the third member creates a weight off-set and imbalance that can be a challenge to control. Once the sombrero is engaged, the factory bolts can be replaced and torqued to spec. This is a method that made my dis-assembly and assembly go easier. I'm glad you got it out safely, I needed a five foot pry bar to separate one I had done.
You might like to put some heat wrap on your exhaust pipes, to better shield the new composite spring from heat.
You might like to put some heat wrap on your exhaust pipes, to better shield the new composite spring from heat.
Last edited by Red 69; May 8, 2011 at 10:35 PM.
Thread Starter
Instructor
Joined: Sep 2008
Posts: 216
Likes: 0
From: Eugene OR
Good Luck!
