How to Diagnose and Repair Your Imperial's Rear Springs

Imperial Homepage -> Repair  -> Frame, Spring and Shocks -> Rears

Tip from Rob (1960):

Got the springs in my over-arched '60 de-arched this week. Done by a shop on Sunset Blvd. that's been there for 62 years (6009 Sunset, block and a half east of Gower on the North side of the street, if anyone needs to have the service performed here in LA). There was a 1940 Darrin-bodied Packard there (beautiful car), but the Imperial got all the attention. Anyway, the car now sits right, looks terrific, and, bonus, the shaking is finally down to a much more manageable level. I can actually hit the pedal hard and she really goes!

Question from Frank:

How does one know whether a car needs new springs or an adjustment?

Reply from Rick:

I had mine re-arched and it has worked fine, good height nice ride. Much less expensive than new.

Question from Charles:

What was the cost to re-arch rear leaf springs? What type of shop does that?


From Rick:

It was about $250 for both two years ago and I looked them up in the yellow pages under springs.  

From Bob:

Yep, I had it done to my '66 for about $225. Another local owner bought new springs and changed them himself. Either approach will make a big difference in your ride quality.

Question from Garry (1956):

My wife (Mary Emily) and I returned last night from our trip to Phoenix to pick up "Babe", a Stardust Blue '56 C-73.
We arrived home in Kansas City none the worse for wear, and with "Babe" running beautifully. The car has a few problems we hope to address in the near future. The first one is that the rear leaf springs need to be re-arched. We have the factory published 1956 service manual and also the Mopar parts book, but can find no mention of the measurements of frame to ground at the rear of the car. There is apparently a difference of 1" between the lower inner and lower outer centerline of the front suspension. We're not too far off there, but we need help finding service information for the rear leaf spring geometry.

Reply from Michael:

There is a company here in Portland Oregon......BENZ SPRING..... that I have used for a new set of springs on my '65 4x4 Panel Truck. they do "top notch" work for an affordable price and I was VERY pleased with the job they did on my truck. I also know that they have a wealth of old spec drawings for all kinds of old cars and trucks. I'm not sure of what they might have for Imperial's but I would be willing to bet that they would have the spec's, as they cater to the old car market here in Portland and are more than happy to accomodate the strange and unusual. They've been around since 1922.

I will be contacting them in the coming months for rear springs for my '58, and I will let the list know of my findings, but I just thought I would pass this along to you now, as you are looking for a resource now.


1-800-452-0509......or in Oregon.....503-224-4865

Question from Dave (1960):

Can anybody out there tell me if you park a 60 Imp up, how high should the back end sit as I think that with having new springs on ours, it is sitting a bit too high. Is there an easy way by measuring either from the road to the top of the fins, or anywhere else on the back end on the car, as this is something that's being bugging me since we parked next to a very nice 60 LeBaron which came over to a show in England from France last month.


From Rob:

They should definitely have an arc to them; they're springs, with no arc they're just slabs.  I just had mine replaced on the '60.  Now the only issue is that, as the springs are brand-spanking new, they're rather stiff, and have jacked up the rear and therefore altered the angle of the driveline, causing a hardcore vibration when hard accelerating from a stop. The vibration occurs at about 17 mph. I'm finding that as the springs are getting worked in, the vibration is slowly lessening (that is when I forget and hit the gas too hard -- usually I go easy on the gas and it's smooth).

From Jerry:

You may have to readjust your ride height since it may be have been adjusted previously to compensate for your bad springs.

Question from Tony (1961):

It is time for me to re-condition the rear springs on my '61 LeBaron.

I don't want to remove the springs until I have the new bushes. Can anyone tell me what size I need? Are they the same size as the bushes for the rear axel stabilizer bars?

Finally, does anyone know of a source for these items?


From Kenyon:

I think that I got mine from Andy Bernbaum. There are probably many other sources to choose from, maybe even local?

I'd ask your local parts-man first on these items - may be an easy item.

From Paul:

I doubt that those bushings are unusual. Last May I paid a shop to build and replace the rear leaf springs on my '55 Imperial. When it came to the bushings, they were able to simply pick them out of a box in the back of their shop.

The spring installation went perfectly, and are now silent while driving down the road. I had made the appointment the week before, and the shop ordered the springs made (to original factory spec's) at that time. When I arrived with the car, I only had to wait about three hours and the job was done.

The biggest clientele for that shop is truckers, and a large volume of commercial services that have stronger springs put on brand new pickups and vans for heavy duty work. This particular shop is in Kent, Washington, but I am sure that there would be something similar in a large city close to your location. My front end shop provided me with the lead when they noticed a broken leaf on the car while they were working on the front end.

From John:

Try a local spring shop if there is one in your area. If not, try Eaton Detroit Spring. They advertise in Hemmings amoung other places & claim to carry a full line of hardware. There was a feature article in Classic Auto Restorer some years ago that was on a 61 300 G & all the parts & springs came from them.

From Jim:

Front of rear spring is the same kit for '60 - '62. We sell a bolt/nut/bushing kit for $25 per side. Rear of rear is the same shackle for '60 - '66 . We supply that as a shackle assy for $35 per side. If anyone wants to advise the Mopar number for individual bushings, we can check stock on them as well.

From Ron:

Springs are like anything else that lives in tension. Sooner or later, the tension goes away. I am astounded by how many cars I see with weak springs! Never let anyone tell you they can re-arch your springs and guarantee they will work like new! Buy new springs for your car when the time comes and the bushings are available from the same suppliers. I use Springs and Things for my cars. They are reasonable, give honest, straight answers, and ship right away. Figure on spending around $200 for rears and bushings. Same folks offer front coils for the old timers and torsion bars for later ones.

Question from Rodger (1966):

Who was the owner of a '66 who replaced their rear springs ? I'm looking for the name of the company who supplied them.


From Greg:

You need to contact ESPO Springs 'n Things. Their number is (800) 903-9019. I have ordered springs for two of my collector cars from them and I couldn't be more pleased. Yesterday I stopped by the shop where I am having work done on my T-bird. The leaf springs had been installed and I couldn't believe how great the car looked. It sat level as it should whereas before the rear end really hung close to the ground. Give them a call. They are really nice people to deal with!

From Bill:

I had my rear springs redone recently at Craig's Auto Springs here in Seattle. I think he just added a new leaf, but the car sits much higher in the rear now.  Total price was about $300.00.

From David:

I replaced my rear springs on my '66 crown coupe and I got them from Kanters I also replaced the rear springs on my '63 from the same source.

Fitting is a pain but can be achieved if you persevere.

From Dan:

I'm not sure, but you could have been referring to me and the problems I was having with getting those #@%$^&$$# rear springs back on my '66 convertible a few months ago. I got them from ESPO's Springs & Things. I forgot the actual cost but if you need it I can go check the book and get you the exact $$$. I also ordered new shackles/bushings and U-clamps for attaching the springs to the axel itself. Although I could possibly have reused some I figured that after so long a time and so many miles I may as well add NEW whatever I could, and the cost for the bushings/shackles was minimal. The lady I spoke with at ESPO's was very helpful and really seemed to know her stuff. In my case, since my car is a 'convertible' the spec's for the springs themselves are a little different than on, say, a 2-dr or 4-dr vehicle. The convertible, being a bit heavier, has different 'arc' and 'radius' figures than the 2/4 dr models would have. Getting the springs themselves back in place was the hardest part of the job!!!! don't be surprised if you start looking for new cuss words as it was not unusual it get everything 'almost' lined up and not be able to force the rear axel just another 1/4 inch or less to get the alignment pins to fall into place. I eventually got out the good-old 'come-along' and managed to get everything to fall in place. What I think (?) happened is that after disconnecting the springs, shackles, and everything else that actually holds the rear axel in place, the axel itself may have slipped back (towards the rear ) when the pressure was removed keeping the driveshaft in the may have moved just enough to cause the problem. If I had to do it again ( and I might have to!) I would try and come up with some way to keep pressure on the axel/driveshaft itself so it would NOT try and back out of the trans. I say I may have to go thru this again since the drivers side of the car is still sitting 1 inch lower than the passenger side. ever since putting on the new springs. I really do not think it is the springs themselves and I have spoken to the people at ESPO's a few times asking if they have had a problem on any other similar springs. They tell me these springs are made in sets of 12 pieces, meaning 6-sets of two springs. And they have had no one else complain at all about one spring being lower than the other. They said the only REAL way to tell if its the springs is to change the left on with the right one, but as you might imagine I am not in any hurry to go thru that again.

From John:

I had springs put on a '63 & the spring shop used a jack under the differential to make minor adjustments to get the springs lined up.

Question from Mark (1968):

The question I have today concerns my '68 and the rear springs.  When you look at the car from the rear, it sags on the right (passenger) side. Some days it's pretty bad, other days it's not too bad.  When you drive the car it seems to right itself - after driving somewhere, when I get out and check it, it's not sitting so low on that side. And when you drive it, you can't really tell you're listing to starboard; it's not noticeable.  Had a mechanic look at it and he says the shock is okay; it must be a spring problem. Question is: how much would a new rear leaf spring cost? If I replace one, shouldn't I replace both? Where do I find one, or can the old ones be reconditioned? Somebody said to put my car up on a jack and let the wheels hang down free for a day or so. I've seen the travel in these springs; when the car goes up on a lift the wheels seem to hang down about 3 feet; I doubt I'm going to find a jack tall enough so that the wheels dangle in air. Any suggestions?


From Bob:

My '66 was badly sagged 18 months ago and I took it to an old shop in Hollywood that does springs & suspensions. The springs were re-arched and one new extra leaf was installed AND the owner installed shocks I supplied - total price was $225. Big difference. You also can get new springs for about anything from Eaton Spring.

From John:

I had the leaf springs on my '65 reconditioned a couple of years ago. It wasn't all that expensive and it made a BIG improvement in ride and handling. The spring shop re-arched my springs and added a leaf.

From Greg:

Springs take a set, meaning, that if they are bent a certain way and then they are re-arched, the springs will gradually work themselves back to the original position. I wouldn't mess around getting them re-ached, the cost doesn't justify the end. New springs are the way to go and the cost is just slightly more that having them reached. When you replace them, replace both of them as a pair. Detroit Spring supplied new ones for my 66 Imp. Compared to a local shop that was going to replace the main leaf and use all the others over again the cost was about $100 more for new, with me doing the installation.......Certainly a better way to go with new......

From Clay:

I have about the same problem with my 67 Crown. Although I don't think mine sags more on one side than the other. I did notice that in the FSM the picture in the beginning of the book of a 67 Crown shows it sagging a bit in the rear. With my Imperial I don't think that it looks so bad as much as it doesn't feel quite right when your driving it.

Question from Mike (1968):

My '68 LeBaron has been fitted by the previous owner with some heavy duty rear springs. It looks that there is one more leaf on the leaf spring. The bad news is that it sits way too high, by about 3". The extra roll stiffness does reduce lean in curves, but the higher CG does not help the overall handling. Also, the car does not look right. Is there an easy way to lower the car while still maintaining the heavy duty springs?


From Nick:

OK, there are really only two feasible ways to lower it and retain those springs. The first, and preferred method is to have the springs de-cambered (de-arched), which will affect the rate slightly, but also return the rear geometry to stock. The other method is to buy some $20 lowering blocks and U-bolts and slap them between the axle and spring. Provided you don't do wheel-hop inducing drag launches, (who would with an Imperial?) they should be fine. brother's 1967 has this problem as well. When I first bought it 3 years ago, it sat perfectly level. Then over the course of time, individual leaves in the rear springs started to break. To the point where it was riding on the bump stops. We had new springs fabricated for it, but the ride height came out a bit higher than we had anticipated. The track bar (panhard rod whatever you'd like to call it) is now sitting at a noticeable angle, and that doesn't help with handling at all. It over-steers in one direction, and under-steers in the other. :) The springs have since settled a bit, but they're still about 2" too high for my taste. I'm too lazy to put blocks under it, and too broke to have the springs de-cambered, so my brother and I will live with it. :)

From Roger:

A extra leaf in each spring should not raise that much. check the shackles at the rear of the spring, where bolt goes through the spring eye. if it is adjustable it should have three holes in it. If it does move up one set of holes. ( I figure someone used the car for towing.) As for the shocks are they gas or air shocks. if the latter let some air out.

Question from George (1981):

Yesterday when I had the oil changed on my 81 Imperial the mechanic showed me a broken U-bolt which is over the right rear "axle" and connects to a plate on the leaf springs. There is a one inch space between the broken ends of the one leg which is broken. This shop does not do this kind of work and he was sure there there was no "spring" place locally. He thought there might be broken springs and that some welding might also be required. My local body shop does excellent work but is extremely expensive. He said they could probably do the job and he has set up a visit for 4/17 to look at it and give me an estimate. There are several "spring" places in my directory but they are 50 miles away. Any ideas what I am up against???


From Brian:

Any competent spring shop should be able to make you a spring for under $200. They probably would only need to replace 1 or 2 leafs, which should be cheaper also a u bolt is cheap($10) and the entire process is fairly straight forward and you shouldn't have a problem doing it yourself.

From Bill R.:

You may be up against no more than replacing a $5 U-bolt, which is NOT a tough job at all. Did "he" explain what "welding" might need to be done? You don't weld spring leaves, if one is broken, you replace it.

From Bill W.:

If there are broken leaves in the spring, you do not need to make an appointment to have the springs inspected. A broken leaf will be very visible when the car is raised off the ground. I know. I have a 1965 Valiant Signet in the parking lot of my apartment with a broken leaf. You can see it, actually, without raising the car. If all you have broken is the U bolt, check with Autozone, NAPA or some similar shop. They probably carry them. Here in Canada there is a chain of Canadian Tire stores that carries U bolts as an off-the-shelf item. Just measure the width needed (ie, diameter of the rear axle where the U bolt is located) and start shopping. And one U bolt is not that hard to replace.

From Bill Reich:

You should take caution driving this car at highway speeds a good bump could break the other one which would cause you to lose the rear end and most certainly do damage to your car and possibly yourself. If its just the "U" bolt its an easy job and your local wrecking yard most likely can help you out from another Mopar like a NY'er or Diplomat. I would remove the broken piece and take it with me to the yard or spring shop. I would think a good auto parts store could get the part for you also.

From Don:

IF YOU ARE TALKING THE "U" BOLT THAT HOLDS THE AXLE ON YOUR car you CANNOT USE A USED ONE.....THEY ARE DESIGNED TO GO ON ONCE ONLY!!! There is a place called "springs n'things" that has the U-bolts, the springs and everything you will need. They are located in Pa. Here is the website for Spring 'N Things.

Question from Jim:

Has anyone tried  helper springs or know of an inexpensive place to buy new or rebuilt springs. 


From Jay:

I have helper springs on the rear of our '66 4-door Imperial. They work fine for restoring the correct ride height (countering sagging springs) and helping improve ride/control/height when hauling the moderate to full loads. I have had no problems with then and I highly recommend them. I got mine for under $50 (including shipping) from J.C.Whitney. Easy to install and I can adjust them myself at anytime using a floor jack and a couple of wrenches. I think that this would be ideal for you to be able to "fine tune" the rear of your Imp for towing. I recommend getting a free catalog from J.C.Whitney. Just give them a call and they'll send one to you. They have a lot of tacky/plastic/funky stuff, but they also have things for our Imperials like cloth windlass, carpet kits, headliners, suspension parts, etc.

From Norm:

Helper springs will, indeed, raise the rear height . They will also alter the characteristics of the spring action and change the ride quality. Some people do not mind, I do.  That is not to say I have not used them, I have. My preference is to re-arc the springs, but not too much . We have gone 'round on this subject before, the FSM of almost every year states clearly that a bit of reverse arc is NORMAL and not cause for action. I can attest to that, especially on the 64 5 6 models as we had a 65 when new and it did the same thing.

This page last updated December 2, 2004.  Send us your feedback, and come join the Imperial Mailing List - Online Car Club