Originally Posted by Bill1947
My wife and I recently bought a 2006 Monaco Diplomat 40’ with a 400hp Cummins.
We love the coach however when steering I need to turn the wheel 3 to 4” before the coach starts to turn. I am used to much tighter steering, is this normal? If not has anyone else had this issue and how did you correct?
We have owned our 2006 Diplomat for 11 years and done many modifications. Now the coach handles extremely well even in North and South Dakota where the winds can be a challenge. Before all the mods the coach would sometimes jump a foot in the lane from a gust of wind or a passing truck. There are many things that can make small improvements to the coaches handling, but as Barmcd has pointed out, the first thing you need to do is get rid of the Sheppard steering box and install the TRW. Everything you need to know is in the thread Barmcd posted. The cost after receiving the core charge back is between $800 and $900 assuming you do the work yourself. If you don't feel comfortable in doing it yourself there are places that will do it for you. Most shops won't touch it because it is a mod to the OEM steering and they don't want the liability. You can post on this site and ask others where they have had their work done. I know Josams in Orlando, FL will do the work and even order the parts for you. They are considered the best in the US for alignment and repair of the Roadmaster chassis.
After you get the steering box swapped to a TRW the next thing you need to do is install a Watts link kit on the front. We have both front and rear Watts links but the front is the one that makes the most noticeable difference. We also have the crossbars on the rear. The crossbars were before the Watts links and they do make a difference. You might consider the crossbars at the same time you add the front Watts link. They are simple and easy to install. You can order the Watts link and crossbars from the following website and also find out more about them there.
I know this is a lot of out of pocket cost but you will think you have a different coach after doing these mods.
While you are at it make sure you have high quality tires that are balanced. Rivered and poorly balanced tires on the front will cause a lot of trouble.
Since we have the same coach, and I have 11 years of experience making modifications and repairs, you are welcome to ask me questions. My memory is not very good any more and when I hide things from my wife and kids they have a better chance of finding them than I do. I do have notes and documentation on the computer and may have what you are looking for.
PS - It would be beneficial if you posted your general location. That way others might be able to recommend shops in your area.