Leaf spring confusion

[Lenny Bruce]

Can someone explain to me the theory on the leaf springs? If the leaf springs are bad the Model A is able to drive top speed or near top speed without any issues with no shocks. If the leaf springs are good and theirs no shocks on the car it will be all over the road and unpleasant to drive? It sounds so backwards to me. I’v only owned my car since May so I’m not being a smart ass in any way but this is very confusing.

[Kurt in NJ]

when the springs are “dry”, not lubricated the friction between the leaves restricts movement, sort of a friction shock absorber , the ride will be stiffer
With well lubricated spring there is little interleaf friction, bumps get softer, but excessive motion, rebound has the be controlled by the shock absorber

[Lenny Bruce]

Ohhhh ok that makes sense now. So well lubricated springs allows a softer ride and without shocks your liable to bounce off the road.

[WHN]

No shocks, bad springs, worn out front end, tires, and brakes. Reflection of a lot of Model A’s out there.

If you do nothing else to your car! Correct these issues back to as close to factory spec’s as possible.

Paint and interior doesn’t matter if your car is not safe.

Sorry for my soap box.

Enjoy.

[aermotor]

Originally Posted by Lenny Bruce

Can someone explain to me the theory on the leaf springs? If the leaf springs are bad the Model A is able to drive top speed or near top speed without any issues with no shocks. If the leaf springs are good and theirs no shocks on the car it will be all over the road and unpleasant to drive? It sounds so backwards to me. I’v only owned my car since May so I’m not being a smart ass in any way but this is very confusing.

Often the leaf springs have been run "dry" for years and the leaves will have a divot in them preventing full travel when extended or retracted. The ends have to be rounded and the divots smoothed out or no amount of lubrication will allow full travel between individual leaves. This would be the same as a near solid piece of metal replacing the springs.

[Jim M]

Sponsored Links (Register now to hide all advertisements)

What is the best way to lubricate the springs and what is the best thing to use. I had the rear end and rear spring off last year for a transmission rebuild. Rear spring was sand blasted , coated and lubed. Only driven about 400 miles. Thanks, Jim

[rotorwrench]

SLIP Plate is likely the most used graphite based lubricant for steel to steel contact such as that for leaf springs.

[aermotor]

Originally Posted by Jim M

What is the best way to lubricate the springs and what is the best thing to use. I had the rear end and rear spring off last year for a transmission rebuild. Rear spring was sand blasted , coated and lubed. Only driven about 400 miles. Thanks, Jim

Any problems with the leaf springs as mentioned in post 5?

[old31]

I agree with Rotor, slip plate is good stuff. It is just difficult sometimes to squirt it between all the springs.

Works great when the springs have been separated.

[PC/SR]

You can do a fair job of lubricating the springs by jacking up the car by the frame rails until the wheels are off the ground. I squirt in some graphite that is used to lubricate key locks. You know, the things they used to start and lock cars in the old days. Pretty soon valets will know what they are either.

[updraught]

More up to date would be PTFE.
https://www.wd40.com/products/dry-lube/