1997 ford explorer steering is jerky even at low speeds. Have seen some power steering fluid under auto but there seems to be fluid in the resovouir. What issues may cause the jerky steering?

the most likely culprit is the power steering box, there is a product available on eBay called leak fix that is designed for power steering systems, I used this on my 96 explorer that was leaking by the pitman arm from the steering box, that was 4 years ago & with 2 changes of fluid since it still hasn't leaked one drip

That could be a number of things. The power steering pump could be low on fluid due to a leak somewhere. The belt that drives the pump could be slipping. There could be bad bearings in the steering column. There could be an internal leak in the steering gear. I have even seen bad ball joints binding and causing similar symptoms. The problem simply needs to be diagnosed.

you have a power steering leak either the pump itself or one of the power steering hoses has a hole in it.the low brake fluid light is probably the fluid sensor in the master cylinder providing the fluid level is not low.the sensors tend to stick and need to be tapped or pushed with your finger until it frees itself.

all power steering fluid is the same actually us can use transmission fluid if u want
now being as you had to add fluid i would assume u have a leak some where in the system
you may be low on fluid also there probably air in system (when u have a leak it also allows air into system especially when you run low on fluid)
also if anyone ever put stop leak in system stop leak is a lot thicker oil and will take longer to heat up and thin out in cold weather to allow easy turning
first check for leaks repair if needed
if no leaks are found drain system add fresh power steering fluid
if that doesn't fix problem you have a bad power steering pump replace pump

the fluid may be low or the power steering pump may be going out.

Air in the system.

Most likely this is your power steering pump - check the fluid and listen again.

The ford power steering pumps are known for a loud noise and even new ones make plenty of noise - especially when you turn the wheels. Keeping them full of fluid helps them be a little quieter.

Have you checked both low beam bulbs? I have seen both burn out close together.Does this have tilt steering wheel? If it does,remove the plastic steering column cover.Check the wiring to the dimmer/turn switch.The connector ends would pull out of the hard shell connector,when using the tilt feature.The wire harness was mounted too tight,and didn't allow for the angle in tilt.

bad electrical signal to the pump. pumps thinks its going fast. the valve that controls the fluid flow to make steeering stiffer at higher speeds is confused.

use electrical contact cleaner and d-electric grease to fix contact problems.
pop the hood and cleans as many connections as possible, let dry and apply a small amount of di-electric grease to those connections, then re-connect the plugs. even do the dme connections to the main wiring harness.

this will solve many electrical contact problems seen in older cars.

I have a similar problem. The power steering felt jerky just the moment you start and drive off. My mechanic flushed out the old fluid with a power steering flush fluid and replenish with new fluid and that did the trick. The old fluid looked clean in the resovior but down in the steering rack, its a different story. The fluid is dark and contained some sludge. No wonder the steering assist was jerky.