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Car rear is up on stands with tires removed. Using bottle Jack, Vice grips etc to carefully and securely raise the end of the spring.
With the first few pumps of the bottle Jack, the trailing arm is moving upwards with the raising the spring end instead of sliding up the spring end bolt. I’m guessing there is something I’m missing here.
I’ve seen videos of doing this with the car not on jacks but access is limited. Should I try to keep the trailing arm fixed in place? If so, how? Do I keep raising the Jack to change the angle of the bolt and spring end until the trailing arm is “free” again?
Safety first. Do you have access to a proper floor jack? The Home Despot and your local hardware store will rent you one for little $. Get a rubber sanding block and put that on top of the jack with the curved surface of the block against the spring. This will keep the jack from slipping.
The geometry of all the parts involved makes the process of freeing the spring bolt and washers from the spring and trailing arm a bit tricky. Also, if your rear spring was not perfectly aligned when installed and/or has been displaced, there will be a longitudinal force being applied to the bolt (forward on one side, aft on the other).
Carefully jack up the spring slowly and see if the bolt is in the middle of the spring hole or offset forward or aft. Cut a 2x4 to use as a wedge between the trailing arm and frame to inhibit the arm movement. SLOWLY continue to jack and observe the interaction between the bolt, spring and arm. Jack only enough to get the bolt free.
I have heard it is easier when you have the trailing arm nearly horizontal. It curves toward the front as it goes down, putting an angle into the spring bolt. Spring is longer at that height too, so spring bolt is much more vertical that way. Block it at that height between the TA and the frame. But you will have a lot more load on the spring that way, and it will need to drop 6" or more to unload it.
I heard clamping a small 2x4 piece to the spring inside of the jack with a c-clamp is a great idea so the jack does not slip sideways.. Saw one guy using vice-grips clamped there.
The spring will have a lot of angle on it right before it is completely unloaded and would tend to kick out the floor jack (not a bottle jack). It needs to roll sideways a little..
The 9 leaf spring, as shown, has around 8.5 to 9.5 free arch when completely unloaded and is almost dead flat when installed in the car. Be prepared for this. Notice the almost 45 degree angle of the spring end at this point, which is why you want a block of wood clamped to the spring, so the jack doesn't slip.
It has 1000 lb of force stored in it when flat, so it is best to release it slowly and carefully.
Car rear is up on stands with tires removed. Using bottle Jack, Vice grips etc to carefully and securely raise the end of the spring.
With the first few pumps of the bottle Jack, the trailing arm is moving upwards with the raising the spring end instead of sliding up the spring end bolt. I’m guessing there is something I’m missing here.
I’ve seen videos of doing this with the car not on jacks but access is limited. Should I try to keep the trailing arm fixed in place? If so, how? Do I keep raising the Jack to change the angle of the bolt and spring end until the trailing arm is “free” again?
On the issue of ride height change due to the new cushions. I noted somewhere previously on the Forum to assume about a 1/2 inch increase in ride height for every 1 inch of cushion thickness. As such, I recall it mentioned that the cushions could be cut to reduce or eliminate the height increase. Has anyone done this? Thank you again. Tom
It will depend on what kind of material cushions you are replacing with. The Durometer (Shore harness) of the new cushions will vary widely - the higher the number, the greater resistance to compressive loads. If you are replacing with new rubber ones (I would recommend), you would have a slight increase in ride height as your old cushions are pancakes. In time, those new ones will compress a bit more so I would not worry about that.
On the other hand, if you decided to install poly cushions, you won’t get much compression at all, resulting in an increase in ride height by the difference in installed thickness between the new and old which will be more than with the rubber cushions. You can compensate by installing bolts that are longer by the difference in cushion height but if you do, get grade 8 bolts.
Progress today; success in raising the spring to free the end bolt. Of course, the nut is being quite stubborn at the moment. Don’t think it’s ever been off. Repeating with PB Blast. Same on both sides.
Progress today; success in raising the spring to free the end bolt. Of course, the nut is being quite stubborn at the moment. Don’t think it’s ever been off. Repeating with PB Blast. Same on both sides.
Help- Replacing rear spring cushions.
