rearend broken in my c3

[MYBAD79]

The slip shafts are $425 shipped from that shop in Utah. this incl the yokes, U-joints and flanges... just so you have an idea when you talk prices with your local shop....
I took the stock half shaft length (I think it was 13 7/8") and told those guys I needed at least 1/4" travel each way .... I think they have 1/2" travel each way, 1" total.....

 

[tracdogg2]

All the parts used in the telescopic halfshafts come from a late 70's 3/4 Suburban driveshaft. All readily available. But you still need to use the snap rings.(They are not c-clips). To use actual c-clips you need to change to 30 spline stub axles and spider gears. Which, if you are planning any engine mods, you should do anyway. The stub axles in your car are soft to start with and it wouldn't surpise me if your snap rings had long since been ground off and the only thing holding the axle in was the rolled metal on the axle tip. Running the car on the lift might have enough of an opposite load to get the axle to pull through, assuming this is the problem. The fact that you couldn't put it in park tells me the posi clutches are shot.
Although it is common knowledge not run the driveline on a lift the real problem is no one that I know of makes a correct short stroke shock for vettes. Nearly all replacement shocks are longer than original when extended which allows the trailing arm to hang lower and allow the u-joints to bind.
Mike

 

[mrvette]

All the parts used in the telescopic halfshafts come from a late 70's 3/4 Suburban driveshaft. All readily available. But you still need to use the snap rings.(They are not c-clips). To use actual c-clips you need to change to 30 spline stub axles and spider gears. Which, if you are planning any engine mods, you should do anyway. The stub axles in your car are soft to start with and it wouldn't surpise me if your snap rings had long since been ground off and the only thing holding the axle in was the rolled metal on the axle tip. Running the car on the lift might have enough of an opposite load to get the axle to pull through, assuming this is the problem. The fact that you couldn't put it in park tells me the posi clutches are shot.
Although it is common knowledge not run the driveline on a lift the real problem is no one that I know of makes a correct short stroke shock for vettes. Nearly all replacement shocks are longer than original when extended which allows the trailing arm to hang lower and allow the u-joints to bind.
Mike[/QUOTE]

INteresting thought, When I bought my '72 in '95, one of the early mods was to do KYB shocks from VBP along with their 360 lbs plastic spring....

and of course with the ass in the air, the U joints were in a bind...

some years ago I changed to Bilstein shocks from them...and sure enough I can run my ass in the air no sweat....

honestly never thought of it much, just was.....so you provided a 'eureka' moment......:drink:

 

[MYBAD79]

if you really wanted to be able to run the car with the rear up in the air (I cannot think of a good reason) then just add a pair of bump stops under the trailing arm - at the forward frame pocket where the bushing and pivot bolt is located..... that way you can limit how far the trailing arm can drop.
Again, I dunno why you would want to do this but it could be as simple as a plate welded to the frame, two threaded holes (3/8") and a bolted on plate that you shave until it limits the arm movement to where you want it ......
:drink:

 

[fastcompany2]

All the parts used in the telescopic halfshafts come from a late 70's 3/4 Suburban driveshaft. All readily available. But you still need to use the snap rings.(They are not c-clips). To use actual c-clips you need to change to 30 spline stub axles and spider gears. Which, if you are planning any engine mods, you should do anyway. The stub axles in your car are soft to start with and it wouldn't surpise me if your snap rings had long since been ground off and the only thing holding the axle in was the rolled metal on the axle tip. Running the car on the lift might have enough of an opposite load to get the axle to pull through, assuming this is the problem. The fact that you couldn't put it in park tells me the posi clutches are shot.
Although it is common knowledge not run the driveline on a lift the real problem is no one that I know of makes a correct short stroke shock for vettes. Nearly all replacement shocks are longer than original when extended which allows the trailing arm to hang lower and allow the u-joints to bind.
Mike[/QUOTE]

INteresting thought, When I bought my '72 in '95, one of the early mods was to do KYB shocks from VBP along with their 360 lbs plastic spring....

and of course with the ass in the air, the U joints were in a bind...

some years ago I changed to Bilstein shocks from them...and sure enough I can run my ass in the air no sweat....

honestly never thought of it much, just was.....so you provided a 'eureka' moment......:drink:

well i can say it did not seem nearly low enough to be in a bind. the shocks that are on it are monroe air adjust. had them on there after the mount on the the diff. for the springs cracked and i welded them. i had spun the wheels freely by hand and seen no binding. i can understand that u-joints being at an angel speed up and slow down and that can do some odd things but i think my axles just pulled out.. don't know what all that did though.