garys 68&72

I'm going to go through the differential on my 72. Just debating to do it with the rear on the car or remove the whole rear end.
If I decide to remove the rear end, will the springs fully extend (decompress) with the shocks disconnected and the 4 link in place? Or will a spring compressor be required?
I don't want to be dodging any flying springs.

70cutty

I usually just use the jack and let it down real slow.

Oldsmaniac

Jack up rear to undo shocks and lower rear and the springs should be able to be pulled out. The worst part of removing the rear is getting the bolts out for lower control arms. Freqently they are rusted solid to the metal sleeve in the bushings.... that is a pain.

garys 68&72

That was quick, thanks!
I suspect I'll pull the rear out. Torquing the crush sleeve, while laying on your back under the car is a pain.
BTW, already went through the control arm bolts a couple years ago...shouldn't be bad now.

Allan R

You likely will need to replace the rear upper and lower control arm bushings too. BTW, you also need to undo the center brake hose line. If it's original you might want to think about replacing it. The ones from NAPA are as close to OEM as I've found. Only thing not mentioned by anyone is undo the e brake connector (mickey clips) by the lower control arm. Since the rear end is out you might as well clean it up, and redo the rear brakes too. It just never ends.

Did this overhaul on my 72 2 years ago. Much easier with the whole rear end out. Then you also can drop the tank and clean up the bottom of the car, as well as redo the rubber lines from the fuel tank to the main line and vent cannister.

garys 68&72

Thanks for the advice.
Already did new brake lines, went through the drum brakes, new axle bearings and seals, new lower bushings and adjustable upper control arms a couple years ago. All new fuel lines too.
I'm just changing the rear end gear ratio and tuning the posi clutches while I'm at it.
Yeah.....I know, should have done that when it was apart. Just didn't know at the time what ratio I wanted.

joe_padavano

You can do this without opening the brake system if you want. Unbolt and remove the axle shafts, which also unbolts the backing plates. Bend up the clips holding the brake lines on the housing and remove the bolt on the flex hose and the brakes are now loose from the axle. Hand the backing plates from the inner fenders with coat hangers and now you can R&R the housing without needing to bleed the brakes.

monzaz

It appears from the pictures you have a Chevy 10 bolt 8.2 rear under the car...Just so you do not buy the wrong parts. Jim

PM if you need more answers or parts.

garys 68&72

Yep monzaz, that's exactly what it is. Good eye for so late at night.

monzaz

Yep, Just shim the carrier up and you should be good... The steel clutches last a long time. You can shuffle them also. Jim

garys 68&72

Yeah, got the ring/pinion I need and a rebuild kit.
Figured I would wait and see the condition of the posi clutches before I order those.

oldsguybry

I don't want to be dodging any flying springs.

Usually you can't dodge them .

garys 68&72

Yeah,
In spite of the good advice I get here, I'll probably put a chain around the first one anyway.
My biggest fear was that the upper control arms would have to be removed for enough travel in the axle. And that could also allow the axle to rotate....and springs fly out.

Allan R

When you undo the shocks and lower the axle, it will release almost ALL the energy in the rear springs. They will be able to just slide out. No chain required at all.

joe_padavano

^^^This. There is no stored energy and the raised features on the spring mounting pads prevent the springs from coming out until the axle is all the way down. Don't lose any sleep over this. In my experience the springs usually just fall out when the axle is down far enough. If you only do one side at a time, you might have to push down on the housing slightly to get the spring out.

Allan R

I found that when the axle is dropped, all I had to do was push down on one side rear brake drum. That makes more than enough clearance to lift the spring out. If you can't reach to do this, you can also put a jack under the opposite axle tube and force it up, which will drop the side you're working on more than enough to lift the spring out. When you have one spring out, the other is even easier to get. Reverse the process to install the new ones.

Never thought about pushing down on the pumpkin. Good tip.