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Tightening leaf springs on 68 Coronet

Hilljack68

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I'm in the process of installing the rear end and leaf springs on the Coronet. Need a little help with tightening procedure. I hung the leafs from the rear shackles - just finger snug. I attached the front hangers, and torqued them down. Question is, do I torque the shackles before I put the car on the ground, or after? Thanks fellas.
 
A service manual explains this in full detail....

Torque front hanger when off the ground the rest just tighten more than finger tight. I then put the car on the ground and seat the springs by pushing down on each corner several times. Does this do anything maybe, maybe not but I do that....Then torque the front hanger eye bolt and the rear shackles. Make sure you have the eye bolt in the correct way, the nut faces out....
 
Torque the shackles after the car is setting on the ground.
 
lower the car on the ground and then torque your bolts
 
When I tightened my front bolts after car was on ground, they really wher noisy, back nut off 1/4 turn quiet just curious is this normal.
 
For sake of argument. the shackles and bushings are cone shaped. Tighten them down before putting weight on them and deforming the bushings. Centering the bushings in the cone shaped shackles..........................MO
 
Yeah, everything I've read says the same thing you guys do... but it just looks like it shouldn't work. I have the rear end sitting on the leafs, and tightened down; the car's still on the jack stands; both ends of the leafs are still loose... but the shackles are sitting pretty much up against the frame rails - dang near horizontal. Do the upper end of the shackles get tightened, or leave BOTH upper and lower ends loose?
 
The springs are installed without the weight of the axle. Tighten bolts to 30 ft-lbs with the springs hanging. Then install the axle on the perches. Lower on ground then torque to specs.(the service manual will go into more detail, but this is the basic)
 
Ok, I answered my own question. For future reference, leave BOTH the upper and lower shackle bolts loose until the car is on the ground. The leaf springs will compress, driving the shackles into the correct position. Once this occurs, torque the front pivot bolt, then the shackles, then the shocks. Boom! done. So, as odd as it sounded to me, yup - torque the upper and lower after the car's on the ground.
 
Ok, I answered my own question. For future reference, leave BOTH the upper and lower shackle bolts loose until the car is on the ground. The leaf springs will compress, driving the shackles into the correct position. Once this occurs, torque the front pivot bolt, then the shackles, then the shocks. Boom! done. So, as odd as it sounded to me, yup - torque the upper and lower after the car's on the ground.
OMG ! my whole third member and springs are going to fall off when I am going 70 mph !!! I didn't follow this procedure. Just jokeing, but in all my years, I have never even heard of any problem installing leaf springs, shackles and shocks in an improper way......................MO
 
Fun fact: The U bolts that attach the axle housing to the shock plates are torqued to 45 ft/lbs
 
in all my years, I have never even heard of any problem installing leaf springs, shackles and shocks in an improper way

Sorry son - guess I'm just an idiot. Thought FBBO was for, among other things, asking people who aren't idiots to help with a question or problem. But thanks for being there for me.
 
Fun fact: The U bolts that attach the axle housing to the shock plates are torqued to 45 ft/lbs

I wonder how much this varies as I've read 55lbs on some and 50lbs out of a '64 Chrysler manual.
"(4) Tighten the spring U-bolt nuts 50 foot-pounds
torque and shackle bolt nuts 40 foot-pounds torque."

Also, is there a torque box wrench on the market? Because there's no way to torque the upper shackle bolts with a socket.
 
Sorry son - guess I'm just an idiot. Thought FBBO was for, among other things, asking people who aren't idiots to help with a question or problem. But thanks for being there for me.
Nope, didn't say you were an idiot, If you have questions, you should ask... It was a joke in case you didn't read very closely. I am surprised that there is a shop manual procedure..seems a little **** to me tho --what is the consequences?? None I have ever heard of . That doesn't mean that there are none..........................MO
 
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