there are quite a few wheel bearing problems on these and sometimes differentials front and rear
if is model with computers etc,most probable cause is the cam positioning sensor
If the rear window is not fully closed the rear wiper will not operate.
when overheating occurs at highway speeds the cause is usually. a radiator or coolant circulation problem, Check for a restricted or clogged radiator.
Go to a tire shop and see if your tires are balanced correctly, if your tires are out of balance they could cause vibrations at highway speeds.
Try disconnecting the vacuum line at the EGR valve and plug it off with a cap or screw into the hose. The diaphrams get weak with age and seem to cause 99% of the surge issue. If not check the internal coil / power packs.
Yes. So could a broken belt in your tire, a tire out of balance, loose lug nuts, bad CV joint.
if you are not low on oil it could be a week oil pump most likely which can be detrimental in a hurry.
If your car is running well otherwise try replacing your spark plug wires. It worked for my 98 that was missing at highway speeds.
If ice remains on the inside of the wheel you may experience symptoms of an unbalanced tire including heavy vibration at highway speeds. It should go away when the offending ice melts or falls off.
Possibly your speed sensor. My speedometer would bounce around & then soon after it felt like my transmission was slipping. Turns out the speed sensor controls the upshift in your transmission.
Check the operation of the cooling fans. However, if you are driving at highway speeds the cooling fan would not be needed, therefore it could be a defective thermostat or a clogged radiator, in which case a radiator shop could clean and refurbish it. If not driving at highway speeds, the check not only the fan, but the thermostatic switch controlling the fan and the fuse/circuit breaker for the fan system
May need to have the tires balanced, May be bad tie--rods, A bad u-joint can cause a bad shanking too. Belt could be brokin in a tire. Check these things first.