2004 Holiday Rambler Endeavor DP.

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One of the more obscure problems that affects steering and wandering is apparently a too-new, too-tight front end. By this I mean that castering only works if the vehicle can basically self-steer mostly straight down the road itself. This means it can bump minor obstacles, the steering wheel may momentarily wobble, but it should return to straight by itself, including after a turn.

The problem manifests thusly:
One finally gets the truck going straight when some minor bump changes vehicle direction just slightly. One must now slightly steer to correct, maybe an inch of steering wheel travel arc. The truck then religiously follows this slightly new direction and several minor overcorrections later, it's straight again. Until it again hits some very minor road deviation. Then the whole thing starts over. It acts like there is a vise grip under the dash binding the steering shaft. The attention requirement is like trying to balance a narrow coin on edge. Then the coin gets periodically bumped and falls. A wide bushing on edge would remain upright, even returning to upright when slightly leaned. That is the sort of low-attention caster stability one needs when driving.

The reason I am aware of this is I bought a used F-250 and it doesn't steer right, constantly requiring close attention to correct the path. The steering is definately sticky (TSB) although one might be first tempted to assume looseness or alignment issues. It is not loose and alignment is correct. There are several things that do cause tightness or binding and I am working on them.

Wes
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How many miles are on the motorhome? Before spending any more money see how it drives with these repairs.

I took my rv in to a repair shop that does rv's and large trucks. they checked out the front end and brakes. The brakes are glazed over and that is the cause of the growl when applying when backing up. The tie rod ends are worn as well as both king pins and bushings. the shop manager took me down in the pit to see. I have done a lot of auto repair many years ago and know what I am looking for and he was correct. Its in the shop being repaired so I am anxious to see what kind of improvements that will make. I took DSDP Dons advice and read Sway article on another site and It was very informing. I called Source Engineering and Talked with Jim and he was very knowledgeable about my problem. He is recommending to purchase and install his sway bar kit including the precision tuned gas shocks that are part of the kit. Kit sells for $3300.00 Thanks for all the input above . Has anyone used this kit before? Kit #REK-281.

As Don said, there are multiple items that can create a steering problem. With our 2005 Endeavor, it was the alignment that was out from the get go. The truck tire dealer (Purcell Tire) in Yuma had the Roadmaster specs and found the Toe to be way out. When he adjusted the Toe setting, it became a completely different driving machine.

Forget the brakes, unless there is over 150K on them, then just have them checked. You will find the drum rusted and the shoes in good condition.

The Monaco's were notorious for making that grinding noise if parked in wet weather. The drums rust up, but the rust goes away in the first few stops. If it continues you have another issue.

Before you start throwing money at this or adjusting the steering box etc, read this thread. It's from the Monaco Forum on another site. It talks about adding pan hard bars to the rear end which has worked miracles on the Roadmaster chassis.

I had a 2005 Monaco Diplomat, sister to the Endeavor. There are three mandatory things that need to be done to correct the basic issues. First, get the coached weighed and adjust air pressure accordingly. Second, get the ride height checked and adjusted, easy to do yourself if you're handy, on a Monaco. Third, replace the shocks with the Koni's FSD's. They're pricey because you'll need eight of them. If you're on a budget, do the front first.

Many of us added the Source engineering Sway bars front and rear and made the coach ride and handle much better.

Read this article on another forum (Monaco Forum). It discusses the issues. You'll see there is a guy who is making pan hard bars that makes the Monaco chassis ride like it's on rails.

Sway

If the RV had sat unused for a period of time, you could have rust build up on the front rotors or a sticking caliper.
I don't understand the "lost motion" comment. All vehicles will drive different so it may just be that the vehicle drives in a manner that is inconsistent to what you are used to. If the front end seems to wander or feels light it could be something as simple as the vehicle IS light and will drive differently when loaded for travel.