'79 Differential Removal
10-23-2018, 01:05 PM
#1
Advanced
Thread Starter
'79 Differential Removal
I'm going to be removing my rear diff soon to get rebuilt since my side yokes have a TON of play in them. I'm looking to see if anyone has any tips or warnings about the process. My trailing arms have been rebuilt before and most of the commonly frozen bolts are new so I'm not expecting too much trouble in that department.
I'm thinking maybe the diff. crossmember might give me some troubles. When reinstalling it am I going to need to replace those bushings or can I get away with reusing them (they look pretty dried up)?
I'm mostly just looking to see what other people do when removing the diff, parts that should be replaced along the way, things to look out for, what people struggled with the most, any special tools I might want, really just anything that will make this process smoother.
I'm thinking maybe the diff. crossmember might give me some troubles. When reinstalling it am I going to need to replace those bushings or can I get away with reusing them (they look pretty dried up)?
I'm mostly just looking to see what other people do when removing the diff, parts that should be replaced along the way, things to look out for, what people struggled with the most, any special tools I might want, really just anything that will make this process smoother.
10-23-2018, 05:59 PM
#2
Former Vendor
Member Since: Aug 2006
Location: Jeffersonville Indiana 812-288-7103
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St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
For us, we put the car on a lift (I hope you have one)
We remove the spare tire carrier, and if the car has under car exhaust we remove the rear section of it.
We then use a long 8' 2x4 to pry the spring on the outer edge upward, if you do this you use the strut rod as close to the spindle support as possible so you don't bend the strut. In doing it this way you can remove the nuts from the end of the spring. You'd be amazed at how easy this is.... If you don't have a lift though you'll need to clamp an L bracket on the spring and place a floor jack under the edge of the spring (not an easy task).
Then mark the position of the camber bolts to the center bracket, remove the camber bolts and swing the strut rods out of the way once done remove the center bracket from the carrier.
Remove the 1/2 shafts, the drive shaft (again marking their positions in relation to the respected yokes...
Then remove the spring from the rear end, the four center bolts.
Then take a transmission jack and position it under the rear carrier. You can and lightly put tension on it.
Next take the outer bolts out of the crossmember and sometimes you'll have to pry it loose. Once you get it loose the rear end is out. Once you get it out you can inspect the condition of the outer bushings, if they are bad replace them if not re-use them.
Sounds simple... but getting the bushing to release from the frame can be quite a task sometimes.
Willcox
https://willcoxcorvette.com/
http://repairs.willcoxcorvette.com/
We remove the spare tire carrier, and if the car has under car exhaust we remove the rear section of it.
We then use a long 8' 2x4 to pry the spring on the outer edge upward, if you do this you use the strut rod as close to the spindle support as possible so you don't bend the strut. In doing it this way you can remove the nuts from the end of the spring. You'd be amazed at how easy this is.... If you don't have a lift though you'll need to clamp an L bracket on the spring and place a floor jack under the edge of the spring (not an easy task).
Then mark the position of the camber bolts to the center bracket, remove the camber bolts and swing the strut rods out of the way once done remove the center bracket from the carrier.
Remove the 1/2 shafts, the drive shaft (again marking their positions in relation to the respected yokes...
Then remove the spring from the rear end, the four center bolts.
Then take a transmission jack and position it under the rear carrier. You can and lightly put tension on it.
Next take the outer bolts out of the crossmember and sometimes you'll have to pry it loose. Once you get it loose the rear end is out. Once you get it out you can inspect the condition of the outer bushings, if they are bad replace them if not re-use them.
Sounds simple... but getting the bushing to release from the frame can be quite a task sometimes.
Willcox
https://willcoxcorvette.com/
http://repairs.willcoxcorvette.com/
10-23-2018, 07:02 PM
#3
Team Owner
Wilcox covered it all
My half shafts needed new Spicer solid u joints. I only removed them from the center differential and let them hang down
I removed the struts on the a-arm side so as to not mess with the center camber adjust cams. Then unbolt it from the bottom of the diff.
With all that a out of the way. You can come in with a floor jack from the side and jack up to the outside edge of the spring. Just put a little pressure on the spring. Then remove the nut and let the floor jack come down slow. Repeat on the other side. I've never used any type of clamping device. Coming from the outside works best. Even on a lift I use a screw jack outside of the spring nut.
My half shafts needed new Spicer solid u joints. I only removed them from the center differential and let them hang down
I removed the struts on the a-arm side so as to not mess with the center camber adjust cams. Then unbolt it from the bottom of the diff.
With all that a out of the way. You can come in with a floor jack from the side and jack up to the outside edge of the spring. Just put a little pressure on the spring. Then remove the nut and let the floor jack come down slow. Repeat on the other side. I've never used any type of clamping device. Coming from the outside works best. Even on a lift I use a screw jack outside of the spring nut.
Last edited by gkull; 10-23-2018 at 11:50 PM.
10-23-2018, 07:28 PM
#4
Melting Slicks
One thing I might add use a thread chaser on your threads in the sombreros. Clean threads start quicker and less chance of stripping. I just did this those bolts gave me a little grief.
10-24-2018, 11:23 AM
#5
Advanced
Thread Starter
all great input, I definitely have a much better idea of what needs to happen here. By the looks of it I guess I will be replacing those crossmember bushings. Thanks WIllcox for the detailed instructions.
Is removing the rear portion of the exhaust totally necessary or can I work around it? I'm reluctant to remove it only because there's a particularly stubborn bolt on my exhaust which I've been avoiding like the plague. It's already stripped nearly smooth (thanks, bubba). I know I'm going to have to deal with it sooner or later... just hoping for later.
Also, does anyone have suggestions on which side yokes to purchase? Just looking at ecklers I'm seeing many options like "heavy duty," "for use with threaded endcaps" and more. I'm planning on sending the diff to a local shop for rebuild and I'd like to provide them with a direct swap for the yokes to keep costs down.
Is removing the rear portion of the exhaust totally necessary or can I work around it? I'm reluctant to remove it only because there's a particularly stubborn bolt on my exhaust which I've been avoiding like the plague. It's already stripped nearly smooth (thanks, bubba). I know I'm going to have to deal with it sooner or later... just hoping for later.
Also, does anyone have suggestions on which side yokes to purchase? Just looking at ecklers I'm seeing many options like "heavy duty," "for use with threaded endcaps" and more. I'm planning on sending the diff to a local shop for rebuild and I'd like to provide them with a direct swap for the yokes to keep costs down.
Last edited by Julius Rosenthal; 10-24-2018 at 01:00 PM.
10-24-2018, 06:49 PM
#6
Race Director
I have had to remove an install the rear differential due to the exhaust was all welded up and i had no choice due to the the pipes where they connected to the exhaust manifolds. The studs looked really bad and I had a fear of a problem was just waiting to happen. It is can be done....but it can be a pain..
As for your rear differential being rebuilt . I would HIGHLY advise gettign a hold of 'GTR1999' here on the forum due to he is the guru on gearboxes and is in your area. He lives in Connecticut.
https://www.corvetteforum.com/forums...1-gtr1999.html
Reason I am saying this is due to he KNOWS what he is doing and when purchasing side yokes he will know where to get them and how to deal with them.
DUB
As for your rear differential being rebuilt . I would HIGHLY advise gettign a hold of 'GTR1999' here on the forum due to he is the guru on gearboxes and is in your area. He lives in Connecticut.
https://www.corvetteforum.com/forums...1-gtr1999.html
Reason I am saying this is due to he KNOWS what he is doing and when purchasing side yokes he will know where to get them and how to deal with them.
DUB