Shut off valves are not code everywhere. Common sense, yes. DH has worked on many homes (stick built) with no shut off valves. He did put them on though.

Seems like I remember a class action law suit about those gray pipes.....we had a problem and when DH went to the hardware store for a replacement, the guy told us about the law suit......he had information and we called. All the gray pipes in our mobile home were replaced free of charge.
I wish I could remember more about it. Sorry you are having so much trouble.

There is a lawsuit against most of them. We've had a few leaks in the past but we just fix them, repair the damage and keep going.

We didn't have shut-off's in our mobile home either. DH rant and raved a few times about it, also and then he started adding them. It didn't make much sense to have to go outside and dig through snow to get under the trailer to turn the water off in the middle of winter! It's really a simple process and it's worth it in the end. We finally have shut-offs on all the lines as of last weekend when we replaced the toilet and put new flooring in our really tiny half bath.

The Plumbing Codes do require shutoff valves at the supply line for each fixture except a tub or shower however manufactured homes are not required to be built to the Plumbing Code specs.

I just bought this modular home and didn't realize we had grey pipes and they were recalled. Is there a way to get help replacing these pipes.