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Rear suspension rebuild and CALTRACS install

Smokinnjokin

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Gentlemen,
I am almost ready to execute the mission, rebuilding the rear suspension.
I have a new set of ESPO +2" springs, proper U-bolts, CALTRACS, rear-hangar bushings, and new proper length shocks for the increased ride height. My front spring eye bolts and nuts look very good, no corrosion so I intend to re-use. Shackle bolts look pretty decent also.

Before I start wrenching and disable my car, I want to make sure I have everything I will need. Here's my concerns:
1) My rear end is not quite centered, its about 1/2" closer on the left side and my tires are big enough this causes rub issues. Is it a realistic expectation that I can center it up when doing this spring replacement? Can I move it over 1/4" without cutting off and moving spring perches or centering tabs?
2) I was thinking of using locking nuts to replace the shackle nuts. What thread size are they, everything I have found says 1/2" but no thread info. I would just take a nut off but Im anticipating destroying it in the process, and I'm still driving the car.
3) Am i forgetting any parts or hardware that I will likely need to do this job?

Thanks for the help from those that have been there, done that.
 
Gentlemen,
I am almost ready to execute the mission, rebuilding the rear suspension.
I have a new set of ESPO +2" springs, proper U-bolts, CALTRACS, rear-hangar bushings, and new proper length shocks for the increased ride height. My front spring eye bolts and nuts look very good, no corrosion so I intend to re-use. Shackle bolts look pretty decent also.

Before I start wrenching and disable my car, I want to make sure I have everything I will need. Here's my concerns:
1) My rear end is not quite centered, its about 1/2" closer on the left side and my tires are big enough this causes rub issues. Is it a realistic expectation that I can center it up when doing this spring replacement? Can I move it over 1/4" without cutting off and moving spring perches or centering tabs?
2) I was thinking of using locking nuts to replace the shackle nuts. What thread size are they, everything I have found says 1/2" but no thread info. I would just take a nut off but Im anticipating destroying it in the process, and I'm still driving the car.
3) Am i forgetting any parts or hardware that I will likely need to do this job?

Thanks for the help from those that have been there, done that.
:xscuseless:
 
Pics of what? My pile of new parts waiting to go on the car?
Sounds like you have everything you need at hand to complete the job. The offset condition.. are you referencing from the leaf springs to the inside of the tire? It's a good chance that replacing the springs will bring things back to center unless somethings bent. I don't think the spring perches would be out of location but you never know.
Just wanting to see pics of your new CalTrac setup and your opinion of your purchase.
 
Sounds like you have everything you need at hand to complete the job. The offset condition.. are you referencing from the leaf springs to the inside of the tire? It's a good chance that replacing the springs will bring things back to center unless somethings bent. I don't think the spring perches would be out of location but you never know.
Just wanting to see pics of your new CalTrac setup and your opinion of your purchase.

I have taken the caltracs out of packaging and it seems like quality stuff with good hardware, Likewise the ESPO springs appear to be of good quality. Tried to mock everything everything up laying on the ground and it was a mess, I will take pics and post during install when its up on the lift.

As for the rear end offset, the culprit is either the front spring hangars not bolted quite right, the spring perch location on the axle tube or possibly the rear fenders themselves are not quite the same dimensions. Its only noticeable because my back tires are just barely fitting, this is why I need the extra ride height to clear the inner fender shape on the '67 body where it wants to rub. Right now im getting it with air shocks and 175PSI, not a great solution.
 
Are you sure the rear end isn't centered? Is it closer to the frame on one side or to the fender lip? I've had a couple of cars where the rear end was centered with the chassis but not the body's sheet metal and they both were still wearing the factory body panels....
 
Pretty common for most Mopars to have such tolerance side to side.
 
Pretty common for most Mopars to have such tolerance side to side.

Yup! Measure from the frame rail to various points on the wheel opening and compare to the other side. I'd lay money the sheet metal is off. But unless you're planning sheet metal replacement in the future I'd suggest welding new spring pads on where you need them to be.
 
Yup! Measure from the frame rail to various points on the wheel opening and compare to the other side. I'd lay money the sheet metal is off. But unless you're planning sheet metal replacement in the future I'd suggest welding new spring pads on where you need them to be.
Well, if you want the car to do well on the drag strip, you have to make sure the chassis is in alignment and square and the body is secondary. What I did to one was make one wheel with a different offset to make it fit without rubbing. It launched well and went straight but it was a high 13 car but if it doesn't go straight at that level, it's going to be worse at high 12's and so forth.....
 
So a wheel with a different offset is different than offsetting the rear end ?!?!?!?
 
I only need to move it 1/4”!! Hopefully I can achieve that with stacking tolerances in the re-assembly.
 
F29F5022-CD54-4F42-8E64-4C59894F94CC.jpeg
Got the car up on the lift yesterday and did some preliminary work. Pressed in the new aluminum bushings, checked out all my hardware, and wonder of wonders the original U-bolts and shackle nuts are removeable with an impact. Hit everything with PB blaster and moved exhaust around a bit to clear rear shackles better. I think tomorrow I will execute the install.
 
73646A79-6325-4190-B6ED-DDEBC41DCB0F.jpeg
53C1ECF8-A167-422F-9D12-223DC3940DD6.jpeg
Install successful, looks and drives fantastic. Not only was I able to scoot the axle over just with stacking tolerances, I actually went a little to far the other direction. I am probably going to break torque on the u-bolts and do some aggressive shoving to try to center everything up for maximum tire clearance.
 
View attachment 783395 View attachment 783396 Install successful, looks and drives fantastic. Not only was I able to scoot the axle over just with stacking tolerances, I actually went a little to far the other direction. I am probably going to break torque on the u-bolts and do some aggressive shoving to try to center everything up for maximum tire clearance.
Looks great. Keep us posted. :thumbsup:
 
I have to ask, what size tires, wheels, offset?
I have Year One aluminum Rallye wheels, 9" rear width, 5" offset, and 315/35/17 drag radials fit like Plymouth should have sold them like that.
20180430_141720.jpg
 
My car is a '67, the fender shape radically restricts tire width. Its not the inner wheel well you have to worry about, or the fender lip, its the spot above the wheel well where the fender dips inward that rubs. I took the thick undercoat off that area and replaced with a thin coat, that combined with the raise in rear susp took care of it. 275 50r15 fit just right, perfectly centered.

I did need to retain my air shocks and run 50psi in addition to the +2 springs to get the ride height I wanted (red line on tires just clears the fender lip).
 
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