My 2003 ford explorer bucks when going down the road - but only with snow or rain present. Sometimes, it bucks hard with a hard braking feeling...Sometimes softer like an engine miss from bad spark plug or plug wire. I stopped last week during snowy roads at my local mechanic thinking maybe it's the transmission. We test drove it and it happened once soft and few times medium. He thought it might be transfer case or differential related. He changed the fluid in both and suggested I drive it for a few days and let him know what happens. 5 days later the feeling is still present. Any thoughts?

It is normal that the 4x4 grips on a tight turn if you are on a dry road try it when you have snow or mud you will see that it will not do the same thing. If you keep on going it on a dry road you will brake something in the front diff .

If you have just snow and no tarmac then you can afford to lock the diff, engage 4x4 and keep the speed down!, if you have intermittent tarmac and snow dont lock the diff, but it all depends on how fast you can safely travel and how much slip on the road you expect

Those are your anti-lock brakes. Either there is a malfunction, or you are applying to much brake for the road conditions, which is causing the anti-lock brakes to activate. If the road conditions are slick and hazardous, slow down and start stopping sooner.

I have a 2003 ford windstar.Engine started to run rough when it
used to rained.I would accelarate it until roughness would go away sort of.It lack a little power but if I take it a mechanic they would charged too much money.Anyway, the problem was a spark plug wire in front of the engine, wires that are grouped together with that little pin. One of them was rubbing agains the valve cover and it got worned out current would leak out right there.I discovery it one time that it rainned really hard I had to go out and the wagon started to miss really bad and it wouldn't move.Finally, I got home the next day I looked under the hood to see what I can see and there it was a spark plug wire that one can tell if you know a little bit about cars that current was leaking throw it. I replaced wire problem solved.But now after all of that snow we had the check engine light came on and I am not sure what could be.For I remmerber running over a mountain of sort of hard snow.So it probably broke oxigine sensor wire.

Bucking and jerking --EGR Valve

Explain how a chain driven transfer case, could slip!

most likey it is ur control switch on the door,because water gets on the switch from snow or rain when u open the window a drive through,,do the other switch's operate the windows??,,could be relay or fuses too,,,,

Your brake caliper is sticking. If you do your own brakes, get a set of new pads and replace them, while you are at it pull the caliper apart and lube up the pins, we have had good luck using the anti-squeal brake grease on them, but you may find something better. My mom's montero did this after they lived in Colorado for a year, the road salts and mag chloride that they apply for snow are very hard on the undersides of your vehicle.

You don't, it's all wheel drive, which means it puts power to the wheel or wheels where (it thinks) you need it, so it sometimes is acting like a regular 2WD vehicle, and seamless transitions to 4WD when you need it (like stabbing the gas turning right from a stop in the rain or snow). You can click 4WD HIGH or LOW and force it to power at least one wheel on each axle.

The ford explorer sport track. Will have a short either at the plug of the multi-function switch or 6 inches down where the column bends the wires during tilt.

Sounds like you have a bad spark plug wire. Start the vehicle, then take a squirt bottle of water and spray around the plug wires. You should find it. It'll look like static around the bad one. Also you should get the misfire. You'll probably find a worn area on the wire. Best wishes to you.