Rebuilt the rear diff in my 79 cant get the spring to go back in. I have one side in and the 4 diff bolts started one side of the spring the holes are a inch and a half off from the bolt going in. I can get the spring flat enough but the bolt on one side is way off.

 

The 4 bolts to the differential should be installed in the center of the spring without the ends of the springs attached to the trailing arms. DO NOT TIGHTEN THE 4 BOLTS, Just snug them up

jack up the end of the spring and install the long bolts to the trailing arms, if the arms are hanging then the bolts will be on weird angles don't worry about it

Once the spring is installed, the weight of the car needs to be on the spring (basically the car on it's wheels) before you torque the 4 center bolts to the differential
M

 

I have one side in and the 4 bolts are not tightened down the bolt is way off will removing the strut rods give me a any play to get the trailing arm bolt to line up on the one side?

 

post 22…get arm up

https://www.corvetteforum.com/forums...estions-2.html

 

Don't do anything with the strut rod (that would make it really hard to put back in once the spring was hooked)
Raise the arm up to approx. ride height using a jack or straps or whatever and you should be able to convince the bolt to fit
M

 

So put a jackstand under the control arm and that will give me the room i need ?

 

Yes it will .

 

Spent another 3 hours unbolted it all still cant get the one side. 4 jacks still nothing, the problem is the bolt is not even close to going in the hole i dont know if its cocked or what.I am on the ground solo.My only idea is to hook a chain or strap to the spring and try to pull it towards the front of the car to get the bolt to line up.

 

Nothing about that looks safe
M

 

The spring is the correct width and sitting properly on the diff carrier?

Use a clamp and jack the end of the spring up into approximately the right height (ignore the adjustable wrench here)



Be careful, jacking that end of the spring is close to lifting the weight of the car, not sure if that center jack in your image is the only thing holding the car in the air there???? The car should be on jackstands on the frame and nothing under the diff or spring
You should be able to bring that bolt down into the spring, the trailing arm is hanging so the bolt moves inwards and towards the front of the car slightly but not a huge amount
M

 

x2
please make sure stands under frame..
That spring is a pita because it curves so much..
i jacked it control arm to approximately drive height and put a jack under it.
the jack up spring as mentioned already
BeCareful!!

 

You should have the bushing cup swaged to the spring end, then Jack the spring end up and lower the TA until you can slide the bolt through. It will not line up until the wheels are on the ground.

 

The image is just how i left it for tonight. I had two 3 ton jacks on the frame a jack on the end of the spring and a jack under the shock mount. i have jacked it every which way possible the closest i got it was in the first pic the bolt was an inch away from the hole at best. maybe take the lower shock mount off and see if it gives me anything.thanks for your input will try again tomorrow.may take it and put it on a frame machine so tired of fighting with it.

 

Jes, no offense, but the set up you're using - as pointed out - is an accident waiting to happen. Your bottle jack has a really small base and is sitting on soft ground vs. asphalt or concrete. Your other jack and set up is also suspect - jacks and stands shouldn't be set up on grass that can rather easily give way. If you don't have other jacks under the frame, as pointed out, some really bad things can happen. PLEASE take the advice given above seriously. And when 'jacking' the spring up on the final side, the car will most likely RAISE UP, causing your set up to be very dicey - and there's a lot of energy in that spring.

That said, if you follow the advice above, and make sure your spring bolt is all the way 'down' so you can move it back/forth as you raise the spring, you should be able to get it done.

 

OK, they are a pain (the steel arch ones like that) but many many many have been put on and off thousands of times.
This is the spring you took off (and the diff cover which is different on the 78/79) right?
There seems like gaps at the spring/diff joint there in the picture, is the spring centered to the differential, check with a tape from the end of the spring to the diff ear on both sides type of thing.

When I look at the first picture you posted, the bolt is pushed up through the trailing arm pretty much all the way, normally that bolt would be all the way down hanging in the arm and that will let it swing sideways a lot to meet the spring as you raise it up
M

 

This is a glass spring but you can see how far over the bolt will swing when it's hanging down in the arm all the way and there's no pressure on the spring yet


M

 

All the components where on the car when i took it apart i only replaced the bushings.the spring is in the hole in the diff cover and all the bolts are started so it would have to be centered..the bolt is all the way down.raising the spring high enough is not the issue the hole is off and i am not getting any closer than a inch off no matter where i lift the control arm car height etc.i will work on it tomorrow and let you know what i figure out.

 

its like a balancing act with arm and spring..spring only goes up, but the a arm moves in and outand up and down
again FIRMLY jack stand that frame

 

Lots of confusion here. The Jack and the stands should be sitting at a minimum on some heavy wide boards to prevent them from sinking into the ground and potentially seriously damage you or the Vette. No joke.

Why not start from scratch. Jack stands on the frame lifting the car at the drivers side behind the front and in front of the rear wheel. I would add another in the front on the passengers side to keep the car from tipping but don’t raise that side of the car. Less in the air the better. Lift it only enough to get the job done.

Then a Jack under the arm of the leaf spring as close to the bolt hole as possible. If you notice people use c clamps on the spring to keep the Jack from sliding away. Very important!!

Be certain your bolt is hanging all the way down. It is not in the first pic you posted.

CAREFULLY Jack up the spring. As you do so the whole car wants to rise up so be very careful and make sure that if all hell breaks loose you have a way out.

As you raise the Jack the leaf spring will rise up toward the bolt. The bolt should have plenty of play in it, meaning it’s tip should move in a circle allowing you a lot of leeway with the lining it up with the spring.

If you have it you might put a Jack under the trailing arm to lift it slightly to help with the alignment, you will need to raise the spring a decent amount. If you notice Interpon had a beefy block of wood to help. I had to do the same.

This should allow you to get the bolt on. Drop the car and tighten the diff screws to torque and adjust you trailing arm bolts were needed.

Safety first always. Walk away when you’re frustrated. That’s when accidents happen!!!

Good luck Ike

 

Jes, pull the link bolt down all the way through the arm so the hex head is resting on top of that bushing then pull the threaded end back and over toward the center of the car. Then jack the spring end up and maneuver the link bolt into the spring’s hole.

I had had a similar situation last month. Good luck.