sixt5

what can cause this? Not really any slop in the wheel but you could drive the thing with your pinky. you really have to steady it at highway speeds or else your all over the road.

2+2GT

MS? PS? Might be a valve thing if you have PS. Otherwise, have the caster checked.

kalli

must be PS. i couldn't believe such a thing would ever hapopen with my MS *g*

blue66mustang

Hey Kalli..... Nice color !

II would check the alignment. The power steering valve could be out of adjustment but is mainly just to center the feed to the ram. It doesn’t control overall effort or pressure. If it steers hard to one side and super easy to the other that indicates that the valve is out of adjustment.

MetalEd

That's what I was going to suggest. The caster is currently off on mine (I hope to do it). Driving at normal street speeds I have to constantly turn my wheel left and right over and over in order to stay within a lane. I recently changed the rubbers on my sway bar and now it is easy as heck to steer compared to having to crank the wheel to make it turn before. (worn compressed and over tightened bushings had made it hard to steer), so I really notice the caster being off now. Like the OP mentioned, I feel like I can steer it with one finger and I have to over steer to maintain a straight course..
That's what I would have checked if you haven't changed anything recently. get a FULL wheel alignment, but make sure if you have shop do it, that they have knowledge of older cars. Some shops don't know how or are able to do the older cars correctly/complete. Some don't even have the shims available in their shop. You need to have the caster checked and a proper wheel alignment will also adjust the toe-in and camber.

racer_dave

Check the caster. That is what gives the car its 'feel'. Assuming toe is correct, if the caster is not the same on both sides, the car will pull to that side (we do this on purpose with oval track racecars). If the car wanders, then it may be equal, but not enough caster overall. You can run more caster with power steering than you can with manual steering.

dodgestang

Very easy turns and no road feel is a feature of the mustang power steering, zero road feel.

If you put a larger pulley on the power steering pump it will improve a little to give you a tiny bit of road feel, this is what I did on my 67 when I first got it. That isn't to say your camber and toe in might be screwy because you shouldn't feel like you are all over the road.

1971mach1

Alignment will help, as mentioned but,
these cars had sloppy steering when new and wide tires can make it
worse. The real cure is one of the many rack & pinion kits and while you're at it, add a front suspension upgrade kit too.

sixt5

power steering and recent alignment. did it before and after. aligned to shelby spec.

KMatch

Note: Steering gear is used generically here for the gear box/cylinder/valve/etc.

What you need to tell us is if it does this sitting still. If not, it's alignment related. If it steers to easily in the driveway it's gear related. The only time in my career I've seen a vehicle with overly easy steering it was due to a defective steering gear and you could flick the wheel, release it, and it would go all the way to lock and bounce back almost to the other lock on blacktop. The pump just sends pressure. It's up to the steering gear to regulate this pressure and control it.