Nobody will tell me what's wrong with my car, any ideas at all welcome!

I have a ford kuga, 2012 - i have now taken it to three different garages and all 3 have said "it's a really bad issue and we can't fix it here" and everytime I press and say can you tell me what's wrong with it? They all say "oh its really bad and you need to go to a specalist"... well I went to the specialist and they phoned and said they wouldn't have time to fix it so I asked them to at least give me a list of the issues and they said they couldn't. I'm at my wits end. I don't know what to do.

Basically it is REALLY intense shuddering, like you feel like all 4 wheels are going to fly off, it shakes your entire body and this is at all speeds. It never stops.

The shuddering shakes the steering wheel and makes it quite hard to control tbh. It likes to suddenly jerk around.

One of the garage's said there is Differential oil EVERYWHERE covering all under the car. We haven't noticed any residue on the ground though.

And when you accelerate, it let's you get to about 2rpm and then it just goes dead and slows right down. Like someone's got you on a bungee cord trying to pull you backwards.

We have this car on finance and the finance company can't help. We are stuck and I don't know what is wrong with the car.

Any ideas?