The idea of leaf springs is that the friction of the leaves rubbing against each other causes damping, and it almost eliminates the need for shocks. Coil springs have no friction and require very good shocks.

When I rebuild springs, I take them apart, wire brush them and recoat them with a good black chassis paint. They are easy to work with as you can re-arch them or flatten them demending on the ride height that you want, and you can add or remove leves depending on the stiffness you want. I would not lube the leaves because without a metalized cover, they can not be kept clean and will eventially change stiffness as the grease degrades.....

Alan

 

That's the advantange and reason for using HMW plastic slider strips between the leafs instead of grease. Years ago we would grease the leafs especially with early Ford buggy springs. then wrap the entire spring with a couple layers of electrical tape to keep the dirt out. You would have to rewrap occasionally as the tape deteriorated.

 

So are the Teflon liners a bad idea if the leaves require some friction for dampening?

 

Yes. The Teflon changes the spring damping, reducing the friction and making the spring more like a coil sprig/torsion bar. The Teflon does not change the spring rate. There were some cars that had metal covers over the entire spring with a grease fitting attached to the metal covering. It seems to me that reducing the damping on a truck which is usually a slower moving suspension is a step in the wrong direction. If you want reduced damping and will use shocks instead for damping, then you would use grease or Teflon.

Alan

 

Posey's liners are popular on '32's that weigh 2400#. They use a completely different suspension concept.

 

Springs do one job, dampers do another (besides damping the springs). Springs are not dampers, should not be considered such or expected to do the job of dampers. Ford who was known to be a major skinflint, would not ave put dampers on his vehicles if the springs could have been made to do the same thing. Friction between the leafs is detrimental to the spring operation, causing uneven and unpredictable rate characteristics, and wear between the leafs which causes more friction/wear until the leaf is weakened enough to break. Many vehicles with leaf springs came OEM with friction reducing pads or pucks between the leafs. I want my springs to operate smoothly and predictably so I can dampen them properly. Sorry, but it's misinformation like this that causes people to be dissatisfied with the ride/handling of their leaf sprung truck and make them want to change it for IFS.
Chuck
who is considering writing a book on suspensions and how they work.

 

Leaf springs actually do most of their "damping" through the friction.
Its why a lot of trailers with leaf springs don't have dampers (you won't find a trailer with coils that doesn't though).

Most dampers for coil springs provide about 4-6 times the damping of those fitted to a typical leaf spring equipped vehicle (purely down to the "damping" caused by the friction of the leaves).
If you have greased the leaves, putting on dampers which are valved differently would be a waste, because 2 months later you will be looking at springs that have had most of the grease out of it, and it now will ride bumps like it has no suspension.

I suggest just putting up with it for the time being.

 

i agree that greasing the leafs is very old school and of little value, but years ago it was the best solution we had. Today High Molecular Weight (HMW) Plastic strip or buttons (if your springs have depressions near the ends of the leaf, then you should use the buttons set into those depressions. If the leaf is smooth then use the strips) is the proper friction reducer to use it is very tough and slippery and soft enough that grit will embed into the plastic rather than change the friction. The spring steel will wear before the plastic. A properly shaped spring leaf set is arched in such as way as to minimize friction between them. That shaping is what creates the preload on the spring that will blow it apart should one remove the centerbolt nut without clamping the center of the spring together and slowly releasing the spring tension after removing the centerbolt. If friction between the leafs was desirable they would perfectly nest one inside the other in full contact without preload.
The difference in damper valving required is not due to the friction in the leaf spring, but in the "spring" characterisics of the two different configurations. A coil spring is linear in deflection i.e. if 200# compresses the coil 1" then 400# will compress it 2", 600# 3", etc. A leaf spring is progressive as more leafs are deflected as the spring is loaded, i.e. on a given leaf spring 200# may also cause a 1" deflection, but 400# may only deflect it an additional 1/2" and 600# another 1/4" for a total deflection of 1-3/4" with a 600" load. (these deflections are simplified for ease of understanding, in the real world the deflection is typically closer to exponential) That stiffening under increasing loads and ease of adjusting the rate of deflection is what makes leaf springs ideal for supporting heavy loads.

 

That is one of the best advantages of parabolic leafs (see a pre 05 superduty front end)
That and they are CHEAP

 

guess you haven't priced a leaf and a coil spring lately...

 

Well - they are cheap for what they do.
Having a non-linear coil spring and associated linkage setup to locate an axle is going to be $$$ in comparison to a simple leaf spring.

 

I am about to reassemble my rear leaf packs, as I finished stripping them, priming and painting them. So where do you get a full set of the HMW plastic strips for the in betweens of the leafs?

 

Mid Fifty sells it by the roll. You will need to cut it to length and punch the centerbolt holes. Note, don't use a knife, drill or similar to make the holes. A rough cut will encourage tearing. I would punch the holes by sharpening the end of a piece of thin walled tubing, then use it as a punch, backing the plastic with the end grain of a piece of wood like a short 2x4 cutoff. The endgrain will yield a clean cut and not tear up your punch.

 

Yea, good point about drilling the center holes for each. I was intently reviewing the Mid-Fifty catalog last night drooling over all the new parts and found that they sell the stuff for the rear leafs for $26 and the front leafs for $24. Is that the correct HMW stuff you are talking about?

 

So just to clarify...I should use the plastic liners on my new springs?

I really don't care about how smooth the ride is, just that the springs last and that the shocks are not over worked.