We just have the front hydraulic jacks. When I set it up in my driveway it's just a little bit off but, after a day or so it starts going down on the off door side which is where the three slides are. We have had it set up since Monday and the same thing is happening, feels like we are sleeping on our heads.
Since the 2nd dealer changed the front jack, the cause of the problem may be elsewhere. Why don't you set aside for the moment the idea that the cause of the problem is in the front jacks. If the cause is elsewhere, insisting on fixing the front jacks will just add to your frustration. Focus on the symptom and see if you can narrow down the possible causes.
If you leave it hitched to the truck and run the slides out, and let it sit, do you have the same problem? If it happens when the jacks are not supporting the rig, that would eliminate the front jacks from the equation.
Have you eliminated the possibility that the problem is in the rear of the coach?
1. Level it again.
2. Take a carpenter's level and check the floor, inside, at the rear to see if the floor is level, left-to-right.
3. Check the floor at the middle of the coach.
3. Check the floor at the front of the coach.
If it's not level, at the rear, keep going until it is level. If the middle and front are level, wait until it starts doing down on the off-door side.
4. Use the carpenter's level to recheck the rear, middle and front.
If the rear is still level, but the front is no longer level, there's something going on at the front.
If the rear is no longer level, there's something going on at the rear.
If you do these simple things, you should be able to come to a high degree of confidence as to whether there actually is a problem with the front jacks.