Tranmission slipping. Think I have a leak underneath the motor. What could it be and should I chech it or have it looked at?

This is best solved with 2 people. One person inside the SUV and the other in front of the car with the hood up.
Get a spray can of something innocuous like Glade and look for holes in the firewall. Spray a light squirt of the Glade (or Lysol if you wish) and see if the person inside can smell it STRONGLY. If so, you have found where the air is getting in.
I must admit that I don't think this will find it unless there is a "grommet" that blocks the air flow when you brake and it is flopping around.
What i really think has happened is that the "flue/flap" that is controlled by a lever on your heater/air conditioning and is used to change the air flow from "Fresh air" or "Recirculate" has become unconnected from the control lever. You might be able to access this from in the engine compartment or you may have to squirm around beneath the dash. The "connector" looks like a coiled spring and it slips over rod/pin-like piece that is attached to the "flue/flap." Getting this connector over the rod/pin should be easy. Once that is done and the heater/air conditioner is set to recirculate, your air leak should be gone.

If you think it slips at all,then it will have to come
out & be rebuilt
Check for codes,if there any on your OBD 1 Vehicle
You can go to You Tube Video & if you know your tranmission
model look at the issues & see how they are rebuilt
If you type in ford transmissions on google, you can pick your
car & find it's trans unit model or number

Maybe the ****** fluid is LOW. I had a car once and when the ****** fluid got low, every turn i took was like being in neutral. It is just because the fluid goes to the one end of the transmission when turning. Check the fluid level and if low, top 'er up and watch for leaks!

most likely you need a transmision,.

The $2,200 will give you a new motor,so
what do you think

Don't go back there

You didn't mention how many miles are on the vehicle but your symptom points to a water pump with failed seals. They don't often fail at less than 100K but they can.

There is a small hole at the bottom of the pump housing that allows coolant to leak out if the seals fail to prevent the coolant from ending up inside the engine and damaging it.

u get a second look your self by looking at the transmission u dont have to take anything apart to find the leak the oil pan is easy so check that one first if u see any fluid on or around the pan then the seal is shot that dont mean the tranny will burn up, just keep an eye on the fluid level second the rear transmission seal is located at the back of the tranny where the rear drive shaft slips into the transmission if you notice fluid around there and on the drive shaft thats leaking also but like i said just because u have a few minor leaks dont mean the tranny will blow up just as long as you keep an eye on the fluid level. do your home work and find a good transmission shop that will gaureentee the there work at a decent price.

Check your modulator with a mity vac?if it has one goto library get book on transmission,also chech oil!if it is brown may have burn clutches!!!!

Check the water pump for leaks.

You actually answered your own question. Your transmission is slipping. The reason that it's vibrating is that it isn't downshifting to 1st gear to start. It sounds like it's either in 2nd or 3rd. The leak may have a lot to with it. I'm afraid you need to find your nearest transmission repair shop ASAP.