Slobbering dog on car journeys...advice please!

supermezzo

If the other two are ok with it, have you tried getting them excited about getting into the car and making it a game? You know like when you say to them do you want a walk etc?
Make a big fuss about it to all three of them, maybe hiding titbits in the boot for them etc and new toys which are only for the car and get them all excited about it - you'll find it's a lot easier for her to 'be one of the gang' and do as the others do than to try and just train her not to be sick.
As the others have said, it's a vicious circle as they associate the car with being sick and so invariably, they are. Ours was sick for months until the new car arrived and then bingo, problem solved (an extreme non money saving way to cure the problem btw!).
And as with all things where the pup has a problem, expect it to get worse before it gets better. If you've been holding her and making a fuss, then she will be a bit put out a losing her 'status' of sitting on your knee and will cry, mope, give you the 'bit*h-troll-from-hell" look but she will stop that when she realises that beng with the others is far more fun.

cluuuuur

Our staffy suffered awful car sickness and slobberiness when we first got her. She used to travel on my partner's knee whilst I drove so that he could hold a bag/bowl for her.

When we got the new car, the dogs went in the boot as we got a dog guard fitted. As she was balancing herself (rather than being held 'in place') and was free to move around and look out of whichever window she pleased, the vomiting stopped almost immediately, though the slobber continued.

I eventually started taking her anywhere it was feasible to in the car so that it became something she was used to (rather than a once a week experience) and also so that there was always a reward at the end - a nice walk, a chance to play with my nan's dog, etc. The more she went in the car, the less slobber there was over my windows and interior. And now (touch wood) it's been a year since we've had any sort of canine leakage(!) to clean up. It takes time, but it's worth it!