Rear Shocks and Springs: One Day?

Brakes, Suspension, Rims and Tires

  1. bajajoaquin

    bajajoaquin Senior Member

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    As some may recall, I live in a beach town and don't have a place that I can leave my car apart and immobile. Therefore, I can only do limited projects that can be started and finished in a day.

    My rear springs sag a lot. A previous owner put on air shocks, but they leak air, so sag out after a day or two. Also, the air lines terminate back at the diff, so it's a pain in the rear (heh heh) to air up.

    New springs are coming, but I think I always want air shocks so I can keep it from sagging when full and carrying stuff. I've got a new set and new air lines. My question:

    Can I realistically pull it apart and replace the shocks in a borrowed driveway in a reasonable day (5- 6 hours)?

    What about leaf springs? I've got to get in there to measure the eye diameter to order new springs. Any gotcha's when I do that? Advice?
     
  2. C Body Bob

    C Body Bob Old Man with a Hat FCBO Gold Member

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    Air shocks about 2 hours. Run the line out to the rear bumper. The rear springs for someone not use to swapping them out may take a full day. A couple of tips. Clean the threads on the u bolts which will make it much easier to remove the nut. Spray with something like PB Blaster. Then wire brush. Get them clean & the nut will spin off in seconds. I use a 3 inch deep impact socket with an air gun. And they are off in no time. Support frame ahead of rear axel & floor jack under rear axel. While you have the rear shackles off take them over to a bench grinder & using the wire wheel attachment clean those up nicely where the slide through the bushings. Spray with white silicone greese & reinstall with new bushings. I find it best to loosen each spring in stages & remove tires & place a block (6X6)of wood under each axel tube. As you let the jack down to take tension off springs the rear can rest evenly on blocks. Chock front wheels & as level a spot as you can get. A helper is a plus if this is your first time. As you take tension off one side the other spring is going to react & try to force the rear downward. Hence the blocks & take tension off evenly. Also while you have the U bolts off take them over to the wire wheel bench grinder & really clean them up. The nuts will spin back on by hand then. Good luck & be safe.
     
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  3. polara71

    polara71 Old Man with a Hat FCBO Gold Member

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    Bob is full of sound advice. Knowing you are limited on time and space I may try to back the nuts off of each shackle before I commit to the job. Only from experience do I know the bolts are soft and new shackles are difficult to locate.
    Again from experience I would be sure to order new U bolts.

    I wouldn't install air shocks. I'm sure you have your heart set on them but if you're sagging the rear on a car with new springs you are probably overloading the car. All my cars get new rear springs at 1" over stock height. With a full trunk of stuff, including a cooler and four - six people in the car I've never had a new spring go negative arch on me. BUT that's just my experience. .....
     
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  4. Big_John

    Big_John Illegitimi non carborundum FCBO Gold Member

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    I wouldn't install the air shocks either. The shock mounts aren't designed to take that stress and the shocks are pretty much junk anyway.

    Good advice from Bob and Dave... New U-bolts are a must. If you don't have air tools, figure on a breaker bar to get them loose... Possibly a pipe over the bar.... But then again, a west coast car might not have that issue.

    Since you are have a time crunch, you want to plan your steps... I jack the car up as high as I can. Jack stands go under the frame just in front of the spring mounts. I leave the jack under the center of the rear and jack it up so there's no up or down tension on the springs. One spring at a time, I first remove the U-bolts followed by the shackles. With the rear of the spring laying on the ground, I unbolt the front. Slide the new spring into place and put the bolt through the spring eye. Leave this loose. I like to jack the rear end up just a little and swing the spring up and loosely fasten the rear shackle and then let the rear drop down on the center bolt. Tighten the U-bolts and then do the other side. Drop the car down and tighten the front bolts and rear shackles.

    It's not a bad idea to recheck the bolts after you've driven the car.

    I've never had to do any measuring to order replacement leaf springs.... Where are you buying them? Be sure to have them install the front bushing.
     
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  5. detmatt

    detmatt Old Man with a Hat FCBO Gold Member

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    I agree with Dave and John, NO AIR SHOCKS! Are we clear?
     
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  6. 1978 NYB

    1978 NYB Warfighter FCBO Gold Member

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    I ran air shocks on a B and E cars in the early 1970's. Won't do that again.

    I would start spraying the U-Bolts nuts and shackle nuts a couple of days in advance as often as you can. You want to saturate the nuts and let it penetrate which will make them easier to take off.
     
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  7. Samplingman

    Samplingman Senior Member

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    Air shocks also put an unnatural load on the front end if raised too high, especially the lower control arms. If Ma didn't put it in, it doesn't belong there, IMHO.

    As for the spring swap, Dave has great advise, test those shackle bolts. If one snaps, plan on the car being laid up for some time while you hunt for a replacement, or find all the parts you might need first.
     
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  8. 70bigblockdodge

    70bigblockdodge Old Man with a Hat FCBO Gold Member

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    I can send you a picture of the busted out and welded back in cross member in my Charger. No air shocks. Those are for GM and Fords with bolt in frames and coil springs.
    Proper built leaf springs increase load capacity as smaller leaves go flat.
     
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  9. commando1

    commando1 Mr. Normal FCBO Gold Member

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    I'll happily jump on the No-Airshocks pigpile.
     
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  10. bajajoaquin

    bajajoaquin Senior Member

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    Ahh yes, I remember the universal umbrage at air shocks!

    I wouldn't say I have my "heart set" on them. After discussing it a while back here and 440Sled chimed in about how he runs high pressures with no problems, I'm more just unconcerned, and they're a convenient stop-gap. But I'll take the new comments to heart.

    Back to springs: One of the issues I'm having is that ordering springs involves knowing that there are two sizes, 1" and 1-1/4" eye. I can't get at the measurement with the springs on, and I'm afraid the old bolts will snap when I take them off.

    Other than measuring, is there a way to tell which I have? Did 4-doors or convertibles, or sure grips or something else that I can identify come with one size or the other? If I guess wrong, can't I just get the bushings for that size (since I'm buying new rubber anyway) and use those springs?
     
  11. Yatzee

    Yatzee Active Member

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    Well, if you're going to change the rear springs, I hope you got a damn good torque wrench to do the axle U-bolts tight. This is not a place for guessing on tightness, it has to be to spec. While your at it, get some heavy jacks stands or you may pull the car over on yourself when doing up those U-bolts.
     
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  12. bajajoaquin

    bajajoaquin Senior Member

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    Yep. I'm not lacking for tools. I have a big air compressor, impact guns, breaker bars, torque wrenches, 6-ton jack stands, etc. Just no garage or level driveway that the car will fit in.
     
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  13. Big_John

    Big_John Illegitimi non carborundum FCBO Gold Member

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    There is always someone that has "gotten away" with something like high pressure air shocks. There's people that smoke 3 packs of cigarettes a day and live to be 100 or have walked away from crashes with no seat belt on.

    Having seen and repaired the damage on cars myself, I'd never run them. I also don't smoke and I wear my seat belt. See where I'm going with this??

    Since you are saying it's either 1" or 1 1/4", you must need to measure the rear spring eye.

    Pretty simple.... A cheap caliper will make this easy. First measure the thickness of the main leaf. Take that figure and double it. Now measure the outside of the spring eye. Subtract the doubled thickness from the OD and you have the ID. Since you have a 1/4" difference, you should be able to figure it even if you just used a tape measure.
     
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  14. bajajoaquin

    bajajoaquin Senior Member

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    You're a freaking genius! Why didn't I think of that!
     
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  15. Samplingman

    Samplingman Senior Member

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    He is indeed. I don't dare disagree with Big John.
    :thankyou:
     
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  16. 1978 NYB

    1978 NYB Warfighter FCBO Gold Member

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    Speaking of air shocks......

    My 1978 NYB has Auto Leveling Suspension which is factory air shocks. Mine still work but I have a hose leaking somewhere to the vacuum compressor which is the left front fender well.
     
  17. bajajoaquin

    bajajoaquin Senior Member

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    I'm inclined to think the air shocks have been on my car since the hitch was welded on upwards of 30 years ago. So I think they've been there, under load, for a long time.
     
  18. Big_John

    Big_John Illegitimi non carborundum FCBO Gold Member

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    No!!

    Always question what I say... Look it up yourself or at least think about it. Sometimes I'm right and sometimes I'm wrong. I say things here based on my own experiences and some limited knowledge. Always question it and don't be afraid to tell me I'm wrong.
     
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  19. live4theking

    live4theking Old Man with a Hat

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    I cannot remember where I did it at but when in Texas while in the AF I swapped springs out only with hand tools. When you want something done you figure out how to make it happen. This was when I learned that rearching springs isn't worth the money. If you're sagging, buy new springs.
     
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  20. Samplingman

    Samplingman Senior Member

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    Oh boy, that's means I have to go back and change all of your posts where I hit "agree".
    :D
     
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