Indoor urination behavior with 4 yr old Shepard

Looking for advice or suggestions on working with a 4 yr old male Shiloh Shepard. We've had him since he was about 10 weeks old and he is still not house broken. He was fixed at 6 months. He can be outside all day, come in and within 5 mins, urinates on something. He wont bark to outside, go the door or try to get our attention in any way. But if we ask him if he has to go outside, he prances and runs for the backdoor. If we are home and upstairs, he'll do it down stairs and vice versa. The other day we were sitting at the kitchen table and he just walked up and started to urinate on the chair my wife was sitting in. He is crated at night and has no problem "holding it" till morning. When outisde, he does he thing when he has to. No problems with bowel movements as those are always outside. Our other dog, a 5 yr old retriever/setter mix (also fixed at 6 months) barks when he has to go out, doesnt try to "keep up/cover" with the shepard and hasnt had an accident in the house since he was being trained many years ago.
We've torn out all the carpeting and now have hard wood floors, replaced the furniture with new, sprayed chemicals, rubbed his nose in it, yelled "No" and "bad dog", never hit him for it though, and he just cant get the message through his brain. When he does do it and we find it, all we have to do is ask him, and he will cowl and hide so he does know that what he did was bad. Sometimes we dont even have to find it, we'll ask him if he was bad adn depending on his reaction, we'll go look and find it or if he stays playfull, we'll find nothing. Vet has checked him out and there is no UTI or other seen medical problem.

What can we do? We dont want to adopt him out as we love him and he is great with our kids and so playful, but we are getting tired of this.

Well, you can go outside with him regularly for his 'potty breaks', which are different then his 'play times'. On potty breaks, have her on a leash and stay outside until she goes. Take her outside for potty breaks after meals, after bedtimes, anytime he looks like he needs to go potty, and every other hour. Hope I could help you!

My bluetick coonhound does the whole sneak off and hide thing too. I think that before we got her, she learned that if she got caught, she got in trouble; therefore, in her mind, don't get caught. Through lots and lots and lots of patience and work, 1-1/2 years later, she usually tells us when she needs to go, but still has some accidents. I'm not sure if she'll ever be 100%, but the important thing is that you pay close attention to when they start sneaking off, and then immediately go for a potty break and don't come in until something happens. This gets very tedious, especially if it's cold or rainy, but does work.

The other behavior where they go in the house within 5 minutes of entering is something I have read about especially in puppies. The reason for the behavior is that they are soooo excited about it being time to come in the house that (like children) they just can't hold it and have to go (even if they just went). My setter mix had a littermate that went to the pound two weeks after adoption for this problem. The solution is supposedly to establish a less exciting home entry routine. Make sure it is always at the same time of day, you always do the same activities when you enter (mine always get fed first when they come in, then we walk one hour later, then it's free time to play, sleep, chew, etc with the TV on).