'63 LCC Rear Suspension Rebuild - The Beginning

[mge825y]

Now that I'm done with the front-end rebuild on my '63 LCC, I thought I'd start accumulating parts to re-do the rear suspension. I plan to search the forum for recent posts, but before I go "All In", I thought I'd ask if anyone has done a rebuild lately and if they have any tips?

These projects are like Easter Egg hunts when looking for parts - you get two here, three over there and another one over yonder. Has anyone found a source for most of the parts like leaf springs, and all the mounting hardware and bushings? What about fitment? Are there parts houses one should avoid?

Also, does anyone have a recommendation for a good rear shock absorber to use?

[papawayne]

Hey there...you very probably do not need new leaf springs. A reputable spring shop can clean them up and re-arch them. Ask them to put "slippers" between the leafs when they reassemble, and you'll never have a squeaky spring. They should also, even without your asking, supply new bushings. An even cheaper cure is to have them add a leaf to bring the car up to ride height. A truck shop (or the spring shop) can supply you with new u-bolts (recommended, at least from my point of view) and I've learned on this forum that T-bird insulators are the same thing. My springs came back from the spring shop all assembled and ready to install. The job is actually quite simple, even with jack stands and a floor jack, so you shouldn't have any trouble. Wayne

[action]

If the ride height is low or adding a spring leaf brings that ride height up, the springs are worn out. If the springs are original to the ride, they are worn out.

I would recommend replacement and have a new set of springs made. Either locally or I had a set made at ATS for a 30 year old van.
https://www.autoandtrucksprings.com/index.php?p=home
Set me back just over $300 for a stock set delivered to my home. Included was new grade 8 hardware. U bolts and shackles.

I made a phone call first to discuss what I was doing and the goal.
Hardest part was removing the old set.
After installation the ride was restored nicely. And the droopy rear end was gone.

>>>>>>>>>>>>Action

[mge825y]

Several months ago I was visiting a vintage car restoration shop here in Charlotte. The mechanics were installing leaf springs that had been re-arched by a local outfit. I think they clean em up and paint them too. I remember that they looked nice.

I guess I'll have to figure out which direction to go - Buy new or Re-Arch. I really need to take some ride height measurements first though.

[Solid]

Several months ago I was visiting a vintage car restoration shop here in Charlotte. The mechanics were installing leaf springs that had been re-arched by a local outfit. I think they clean em up and paint them too. I remember that they looked nice.

I guess I'll have to figure out which direction to go - Buy new or Re-Arch. I really need to take some ride height measurements first though.

I bought new front and rear springs from Eaton Detroit that lowered the car about an inch. They came as bare metal, so I had the coils powder coated, and I primed and painted the rear leafs myself. I did not disassemble the leaf stacks, so I occasionally see a little bit of rust from between them, but nothing of consequence and it just wipes off. I could not think of a good reason to deal with the challenges in removing the springs and shackles to replace bushings and get things powder coated only to put back on 56 year old leaf spring packs. It’s way more effort to put those heavy leaf stacks into a truck and take them somewhere to be fiddled with than it is to just have new ones shipped straight to your home.

For shocks I just got stuff off of Rock Auto. There are some minor religions about shocks here, but minor variations in damping and rebound were hard for me to care about on a car with such a primitive suspension and a ride that is already heavily damped by the enormous mass of the car. No shock is going to make a solid axle car with this much mass start pogoing. So I just tried to buy non-generic to limit the odds of breakage or short service life.

[papawayne]

I was a younger man when I had mine done, and for the record, they both fit in a Ford Taurus station wagon with the back seat down. I had help putting them in the car, and the spring place sent out a gorilla who easily carried them into the shop.

[mge825y]

Thanks for the info - All good options to consider. If you buy new ones you have to mindful of potential fitment issues. If you have the existing ones cleaned and re-arched I guess you still have to wonder if they got it back to the correct form too.

Lots to contemplate

[Gerald F. Chase]

Make sure that the positions of the U-joint "crosses" are marked with a crayon BEFORE disassembly.... so that the driveshaft is bolted back in the same places as it was before disassembly and rear suspension rebuild... both front and rear of driveshaft! [You don't want to have either end 180-degrees out of phase from its original positions in the U-joints.]

This is because said constant-velocity U-joints "take a set" over the years.... and you don't want to accidently 'create' a new source of driveshaft vibration(s). There's good reason why L-M engineers installed these "Double Cardan" constant-velocity joints in these Lincoln driveshafts: to eliminate potential source of vibrations. This was engineered with "NVH" in mind: freedom from "noise, vibration, and harshness". These Lincolns had a seven-degree angle from transmission shaft to front of driveshaft... and another seven degrees into the differential at the rear of the driveshaft --- this angle is considerably greater than the otherwise acceptable three or four degrees. All this was because the goal of the L-M designers was to get this uni-body car both low to the ground AND to have a low "driveshaft hump" inside the passenger compartment. So the engine was tilted a total of seven degrees from horizontal... and so was the differential. The Lincoln engineers, under "MacDonald", who had tank experience in WW2, chose to install these more-complex "constant-velocity" U-joints at each end of the one-piece driveshaft... to eliminate "noise, vibration, and harshness", per their self-imposed demands... for FoMoCo's finest product at that time.

[Solid]

I did not disconnect the drive shaft to do mine. I supported the axle tubes with jack stands and attached the new springs one side at a time.

[mge825y]

I put the rear-suspension rebuild on hold. There’s a shop in town that does transmission rebuilds that another Lincoln owner put me on to them. They had a spot open up and I jumped on it. Should get it back next week.

[mge825y]

Well - Resurrecting my old post because I never got around to replacing the original leaf springs and rear shocks. Lots of other projects got in the way...but I think it's finally time for me to replace them.

When driving around, I started noticing that car has a vibration and shimmy that changes when there's a full tank of gas (and the weight) vs. an almost empty tank. I'm wondering if the weight distribution in the rear with old shocks and leaf springs could the source of the problem?

[1Bad55Chevy]

Well - Resurrecting my old post because I never got around to replacing the original leaf springs and rear shocks. Lots of other projects got in the way...but I think it's finally time for me to replace them.

When driving around, I started noticing that car has a vibration and shimmy that changes when there's a full tank of gas (and the weight) vs. an almost empty tank. I'm wondering if the weight distribution in the rear with old shocks and leaf springs could the source of the problem?

If the ride height is correct the springs are not your issue. Shocks dampen the ride and keep you from basketball dribbling going down the road. Usually 100ish lbs of fuel will not change ride quality of the vehicle.

Here are the easy things to check on a 60 year old vehicle before buying springs.

1. When was the last time you replaced the u joints? Worn u joints will cause a drive shaft vibration going down the road.

2. When was the last time you checked the condition of the bushings in the leaf springs? I just replaced the rear control arm bushings on the Mark review my thread Mark iii loose rear axle.

3. When was the last time the tires were balanced? Classics get parked for weeks to months at a time and can often have vibration issues until the tires get hot.

[frasern]

Mark, your car has a double cardan universal in front, a worn centering yoke could cause the u joints to ride out of line. Also, u joints don't always get loose, sometimes they just get really stiff. In my opinion, the only way to really check them, is to remove the drive shaft.
Drive shaft issues usually change under deceleration vs. acceleration.

[1Bad55Chevy]

Mark, your car has a double cardan universal in front, a worn centering yoke could cause the u joints to ride out of line. Also, u joints don't always get loose, sometimes they just get really stiff. In my opinion, the only way to really check them, is to remove the drive shaft.
Drive shaft issues usually change under deceleration vs. acceleration.

A quick method I use for the cars I sell on my car lot is what I call the mirror technique. If you mount new tires on a car or truck and the side view mirror glass still vibrates going down the road then it needs U joints. Sounds stupid but it works!

[mge825y]

If the ride height is correct the springs are not your issue. Shocks dampen the ride and keep you from basketball dribbling going down the road. Usually 100ish lbs of fuel will not change ride quality of the vehicle.

Here are the easy things to check on a 60 year old vehicle before buying springs.

1. When was the last time you replaced the u joints? Worn u joints will cause a drive shaft vibration going down the road.

2. When was the last time you checked the condition of the bushings in the leaf springs? I just replaced the rear control arm bushings on the Mark review my thread Mark iii loose rear axle.

3. When was the last time the tires were balanced? Classics get parked for weeks to months at a time and can often have vibration issues until the tires get hot.

BadChevy - Great questions... I put on new tires this summer and had them speed balanced and the front-end aligned. As for the condition of the leaf spring bushings, I will check that. I found my car in 2017 in a dirt floor barn in San Antonio. It had been there under a tarp since 1997. The leaf springs look hideous and there are lots a creaks and squeaks going on. So I have to assume that the condition of everything under there is suspect.

Your question and suggestion about replacing the U-joints is probably spot-on and I bet is where my shimmy originates from.

I am going to make some calls on Monday to see if I can find a local shop to tackle all this.

Thank!