Independant Leaf Sprung Suspension?

I'm in the process of repowering a late model utility vehicle (Cushman circa 2000) with a Geo Metro FWD motor.

The cushman utilized an automotoive type RWD setup with rear diff and leaf springs.

Of course the metro utilizes CVs and a spindle/hub.

Assuming I can fashion a block to connect the spindle to the axle would it work....ie would it be able to handle side to side/lateral motion?

I'm forced to look at this or a trailing arm type rear suspension due to packaging constraints.

Corvettes, W bodies, and some 80s and 90s F250s have an independent suspension with leaf springs.

You would need to build control arms or something to locate the hubs but the leaf springs could be retained.

I would imagine that something as small and light as a Cushman could get away with using them in a swing axle configuration but I am far from a suspension engineer.

For a swing axle you would need to build a control arm that would pivot in the center, be braced fore and aft, and then rigidly mount the hubs to the control arm. Then secure the top of the hubs to the springs.

Whether leaf, torsion or coil, the spring can work similarly.

Leaf springs have historically been used as lateral locating links, while coil springs cannot.

The strut based suspension used in the donor car used coil springs on struts to locate the suspension laterally. Replace the struts with the leaf springs and it should work just fine with a lower control arm of some sort.

I would build a piece of steel that used the stock lower strut mounts on the spindle and provided a flat place for the leaf spring to attach to. Add gussets to help with fore/aft loads and you should be okay.

not sure what the cushman uses.. but would it be easier to make an adaptor for the engine to the trans?

The Spitfire uses an independent suspension with leaf spring.

The Spitfire, Corvette and the front suspension on an Opel GT in transverse leaf so I doubt it counts to what is being asked. But I don't see why it wouldn't work. Leafs to locate the suspension laterally as mentioned would be the same concept as A-arms w/struts.

Metro engine and samurai transmission?

Had to use a completely different engine/trans than the cushman (11:1 or higher rear gear ratio with no other gear options).

Samurai transmission was an option, but too long, and still requires some creative axle shortening.

I take it simply connecting the upper strut mount to a leaf spring won't provide the lateral support necessary, however the addition of a lower control arm/ball joint will allow it to work.

Early Willys station wagons and Jeepster used a leaf spring as the lower locating arm. I had a small german car the same way except the spring was on top.

so I give.. how is a cushman's stock drivetrain set up? I always assumed it was transverse

93gsxturbo wrote: Corvettes, W bodies, and some 80s and 90s F250s have an independent suspension with leaf springs.

Corvettes use a transverse mounted leaf spring.

93gsxturbo wrote: ...some 80s and 90s F250s have an independent suspension with leaf springs...

Really? I never heard of that before.

mad_machine wrote: so I give.. how is a cushman's stock drivetrain set up? I always assumed it was transverse

The cushmans utilize a small 2cyl or 3 cyl engine located under the seat, connected to a trans much like a standard RWD trans sending its output thru a driveshaft into an automotive style rear differential, although the differential gear ratios are obscenely high.

bravenrace wrote:

93gsxturbo wrote: ...some 80s and 90s F250s have an independent suspension with leaf springs...

Really? I never heard of that before.

On the front axle only.

Haha no one specified transverse leaf or not!

I had an 85 or 86 F250 with the DANA 50 IFS. Leaf sprung. I would have rather had a solid axle.