Leaf Springs - Would you do it yourself?

[SPF Required]

I consider myself a pretty decent “maintenance mechanic” and recently boosted my confidence with some radiator and alternator replacements (thanks to you great folks here). I have always had an internal issue with the ride height of my 300. I am beginning to think the issue is some tired leaf springs. I have been watching some videos about what it takes to replace the leaf springs in these old cars. Seems like something I could do as long as I have a little patience (and impact wrenches).

Curious to hear any stories of folks that have replaced springs themselves. I have room in my garage to do one side at a time (as I would have to turn the car around to get to the other side). I have a floor jack and Jack stands.

I guess thought before I jump into this…. Is there any kind of way to test if my leaf springs even need replacing? Or is it a pretty safe assumption that after 55 years it is time?

 

[65Port]

Rear height looks good to me.. Front looks a touch high. However, what are the measurements?

 

[SPF Required]

Rear height looks good to me.. Front looks a touch high. However, what are the measurements?

Where on the car should I measure to?

 

[Ross Wooldridge]

I did mine - took them off, and disassembled them. Replaced the worn out bushings with new (pressed in by my local shop) and the plastic slider parts, took the leaves over to a spring shop and had them re-arch them and provide me with a new leaf. I cleaned them up, reassembled with graphite lube rather than the zinc plates (as recommended by all the spring shops), using new spring clamps, and they sit bagged and tagged ready for installation. If it sits too high, I'll remove the extra leaf.

 

[CBODY67]

I agree, the rear looks pretty much stock, from the way the lower line of the rocker panel crosses (if extended rearward) the center of the wheel cover. The front, on the other hand, is a bit too high. What you want, for OEM ride height, is that lower rocker panel line, when extended. to cross the center of the wheel cover at the SAME place. Not too low, not too high, but just right.

Just because they are "old" does not mean they are sagged or weak. Would be a shame, to me, to spend the time and money to change the rear springs and the new ones not make any difference in how the car looks when done.

In ANY ride height change on one end of the car, remember to tweak the headlight adjustment accordingly.

"Measurements"? If you follow the directions in the FSM, it can get to be a bit complicated to do it right. By observation, the lower flat part of the lower control arm should be approximately level with the ground, horizontally, at close to the factory ride height. When done adjusting, a final check can be to see how many fingers you can get between the lower control arm bumper and their contact point, on each side, both the same.

Just some thoughts and observations,
CBODY67

 

[SPF Required]

Well I am certainly glad I brought this to the attention of the forum. ….. so the next question is how do I lower the front end. I will also check the FSM, but admittedly sometimes I just dont get what it is trying to tell me. I will also hunt down some videos.

 

[polara71]

HOGWASH! Replace the springs. After 55 years of holding up that 68 they're tired and weak. Just because the car appears level ( which it doesn't) doesn't mean all is good.
These are an integral part of the suspension. Easily replaced with basic hand tools, jacks and jack stands. You won't regret it.

It is always my first suspension upgrade when I purchase an old car.

 

[TxDon]

Rear height looks good to me.. Front looks a touch high. However, what are the measurements?

I agree. Before you do anything else, measure the front end height using the directions and dimensions from your FSM. If it is too high it will cause many handling issues, I know this from personal experience on my wagon.

 

[75LandYacht]

I did mine on my 77 NYB.. lot easier than I thought it would’ve been, just a little time and few curse word and you’ll be very happy with the results.. I had all the hardware powder coated as well.

 

[SPF Required]

Wow! That looks great.

 

[Northcoast300h]

If you replace them, don't do what I did. This was in 2002 when google was just a baby. So I couldn't find stock springs anywhere. Mine were rotted and cracked. I found a spring mfr in Cleveland Ohio where I live. Called them and they said they could make a set. I gave them one of the springs to copy. What they made looked perfect, price was perfect, it fit perfect....Too bad it rides likes a truck. Stiff. Oh well. I learned even if leafs are same measurement, it depends how they are made which gives them the correct flexibility. I think I got truck springs.

Its not a complicated job, but if you're like me, it will be dirty, dangerous and take longer. (I don't know much about the physics of rust, weight and shifting.... so use lots of jack stands.)

Maybe don't replace? Look at the springs with a magnifying glass to see if there are any cracks? If no cracks, maybe just add helpers? Still 55yrs is a long time. I saw one of my leaf springs was cracked, but I didn't see the others that also had hairline cracks until I got them out. (however my 300-H was sitting in a field for over 10yrs rotting away before I got it)

 

[Gerald Morris]

It's absurdly easy and well worth doing. Go to Springs n Things. Spring and Suspension Specialists | ESPO Springs n Things You can order them with a little extra height, or less too. I ordered a new set for our '66, then swapped those into the '68 we got as a replacement when it got totaled. Being both slab sides, it fit nicely, and improved the ride immeasurably. I counted leaves in the old '68 set, and some pissant removed a leaf for the "low rider" effect. My OLD '66 springs are much better than the junk that was on the '68. I had ESPO give me an extra couple inches altitutde to better roll over the cratered trails in these barrios.

God-willing, I can do the front suspension this January or February. I have all the stuff for that job, and the FSM gives plenty detailed instruction. Gertrude wallows at speeds over 75. No good!

 

[Just Carbs]

I did mine on my 77 NYB.. lot easier than I thought it would’ve been, just a little time and few curse word and you’ll be very happy with the results.. I had all the hardware powder coated as well.

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Did you drive the car with those air shocks with both the new and old springs?
I put Monroe air shocks on my 64 with a two-inch sag and the correction results were acceptable at 30 psi.
But the hydraulic part of the shock ain't nothing to brag about.
I'm going to use them till they fail.

 

[70bigblockdodge]

They are not hard to do. Front bushing is a little challenging to change.

 

[75LandYacht]

Did you drive the car with those air shocks with both the new and old springs?
I put Monroe air shocks on my 64 with a two-inch sag and the correction results were acceptable at 30 psi.
But the hydraulic part of the shock ain't nothing to brag about.
I'm going to use them till they fail.

I did yes.. no problems on either set. I don’t use them for that raked look, just to level her out when to trunk is full.

 

[carfreak6970]

I also did the springs in a 70 polara convertible. They are not bad to do. Just make sure you brace the body on a jack stand as well as the axle. I did both at once so I needed an additional jack stand under the pumpkin to keep the axle from rotating on the U joint while I worked. A compact battery impact wrench will make this job sooooo much easier.

I went with ESPO springs and got an additional inch raise for the rear and the high performance springs (additional leafs that came with the 440 cars for that year) since the car was originally a 383 and now a 440. Love the stance (has a slight rake to it which I prefer) and it handles and rides a lot better (plus all bushings in the rear suspension were changed out at this time)

 

[Gerald Morris]

....
I went with ESPO springs and got an additional inch raise for the rear and the high performance springs (additional leafs that came with the 440 cars for that year) since the car was originally a 383 and now a 440. Love the stance (has a slight rake to it which I prefer) and it handles and rides a lot better (plus all bushings in the rear suspension were changed out at this time)

The ride and handling markedly improved when I upgraded the springs and bushings on Gertrude too.

 

[SPF Required]

Thanks for all the intel on this. Definitely boosting my confidence on this being a DIY.

When ordering springs, is there standard part numbers, or are these things basically custom ordered by call ESPO?

 

[polaratherapy]

Can the front end be lowered by adjusting the torsion bars? Back end looks good to me, front is way too high.

 

[carfreak6970]

Thanks for all the intel on this. Definitely boosting my confidence on this being a DIY.

When ordering springs, is there standard part numbers, or are these things basically custom ordered by call ESPO?

you can call or go on their website and use the chat feature. But you basically tell them what your car is and they will tell you what it came with. They should also be able to inform you what other spring options your car could have depending on engine or body configuration (couple vs convertible vs wagon sort of thing). They also have options of raising the rear by an inch or two over what the factory had installed. Depending on the springs they also offer new bushings and hardware for installation.