Shock selection for city driving
Shock selection for city driving
(OP)
I have a pickup (Ford F150) that is retired from farming and used only for city driving. Front is shock/coil spring and rear is shock/leaf spring. The pickup has new shocks. Still it rides rough compared to sedans. I know a pickup is a pickup, but is there a room for ride improvement by careful selection of shocks?





RE: Shock selection for city driving
OR, convert it to air suspension, which I think is cheaper than it used to be. You still need shocks as travel limiters.
Mike Halloran
Pembroke Pines, FL, USA
RE: Shock selection for city driving
Another fix might be decent tires.
It does rather depend what you mean by 'ride'.
Cheers
Greg Locock
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RE: Shock selection for city driving
RE: Shock selection for city driving
Vehicle is 1997 F150 rear wheel drive regular cab long bed 16" wheel 235-70-16 (OEM wheel/tire size). Thank you again.
RE: Shock selection for city driving
The most extreme installation is what hot rodders do nowadays, replacing every suspension spring with an air bag, with air pressure (or perhaps ride level) manually controlled from the driver seat, individually, so the driver can jack up or drop any corner on a whim, as lowriders do to negotiate railroad tracks.
My 2013 Navigator is sort of in between; regular coil springs up front, and air bags (only) in the rear, with an automatic leveling valve on each air bag, and an electric compressor hidden somewhere. So when the load changes, the vehicle will adjust itself to a fixed ride height within a couple of minutes.
The Navigator also uses a lot of rubbery/squishy bits to make the ride quiet and limousine-ish, most of which should interchange with a similar year F150. That's a hint. Some comparative anatomy in a junkyard might improve your situation.
Mike Halloran
Pembroke Pines, FL, USA
RE: Shock selection for city driving
The front suspension of the '97 F150 is an upper and lower A-arm design, not the old "twin I beam". The Expedition/Navigator of the same platform generation should have interchangeable parts with the F150, which SHOULD make front-end parts swapping as easy as it gets. The next step is for you to go into parts diagrams and find out what's different between an F150 and an Expedition/Navigator up front. I would expect different springs and shocks and antiroll bar, but wouldn't be surprised at different control arms and different bushings (which might not be separately available from the control arms).
The rear is another matter. The leaf springs are designed for load capacity without excessive compression of the rear suspension at max load ... i.e. high spring rate. The shocks are calibrated to maintain ride control at max load capacity. The leaf springs likely have minimal bushings between the front pivot and the frame (i.e. NVH goes straight through to the frame). The good thing about leaf springs is that you can usually pretty easily add or remove leaves to customize the spring rate. The bad thing is that reducing the spring rate by taking out leaves introduces potential bad side effects - excessive sag under load (i.e. it will reduce your load capacity - which may or may not be an issue), axle wrap-up under acceleration (because the live axle drive torque twists up the leaf springs), excessive body roll when cornering, etc. Taking out a leaf won't fix the way the front leaf spring pivot goes into the frame.
A trip to a Chrysler dealer for a test-drive in a current-model Ram pickup with coil-spring rear suspension may be instructive. They do sag a lot under load.
RE: Shock selection for city driving
Expedition and F150 use the same upper & lower control arm, same spindle, etc. (I haven't checked Expedition vs. Navigator yet.) So I suppose rear is where the suspension is different and ride difference comes from. Removing a leaf (from a 3-leaf spring) and adding an air bag seems to be the way to go. As Greg indicated above, it may not be an easy job. Thank you again.