Steering Box Play- Sheppard M100 SHIM or Swap for a TRW ?

[Raddster]

Hello Craig (CrazyKnight),

We have an 07 Safari Simba with a sheppard steering gear with so much slop it's quite stressful driving. Just finished up our 1,200 mile drive from southern California and are now visiting in the Seattle area.

Have read the lengthy series of posts where you have most generously shared your experiences with us and I appreciate the time invested and your willingness to share with others. Since we'll be up here in Seattle for a few weeks I thought I'd look for a service center with the knowledge and skill set needed to swap out the Shepherd with a TRW.

I have some photos but can't make out which model of steering box I have. Perhaps your trained eyes will know,

Do you or anyone reading this post know of and can recommend a good repair facility in the Seattle area?

[CrazyKnight]

Originally Posted by Raddster

Hello Craig (CrazyKnight),

We have an 07 Safari Simba with a sheppard steering gear with so much slop it's quite stressful driving. Just finished up our 1,200 mile drive from southern California and are now visiting in the Seattle area.

Have read the lengthy series of posts where you have most generously shared your experiences with us and I appreciate the time invested and your willingness to share with others. Since we'll be up here in Seattle for a few weeks I thought I'd look for a service center with the knowledge and skill set needed to swap out the Shepherd with a TRW.

I have some photos but can't make out which model of steering box I have. Perhaps your trained eyes will know,

Do you or anyone reading this post know of and can recommend a good repair facility in the Seattle area?

Sorry I have been busy lately and not checking in iRV2 now and then.

The number you are looking for is on the flat face, 3 picture you posted, if not on your build sheet. If you lightly scotch brite the area and put a little WD40 on it it should stand out. Your Sheppard number may be different than the example :-).

[YC1]

After all the modifications possible I am no sitting at Josams having an alignment done.

Experimenting along the way I had it thoroughly botched up so needed to get it back in proper order.

Did the test drive and the impact hammers are working away. We are still inside the RV. Mike is our tech. Lots of tattos and a large fellow. Very very good customer service person.

The place is very busy.

[CrazyKnight]

Good day all,

From another forum emailed to me by my good friend Vanwill. Most of the problems, solutions, can be found in this thread but it is a long read. For those of you considering having a shop perform the TRW swap please read as much of the thread as you can. I have posted a few places that will help you avoid issues, and you will be armed with good information for the shop. Go as far as printing our one, or both, of the white papers graciously prepared by great wrench turners here on the forum.

From the email. I will bold the responses.


I posted this at Irv2 but have not had much luck.
Had a PM but my box was full. Let my supporter status lapse by accident.

I had done on my 2000 exe 40’

8 new air bags (tag bags were fine)

4 new front shocks

shepperd box replaced with trw from weller

A shop performed the TRW swap I assume?

my current issue is a pull to the right.

Another issue is involved.

I am also unable to turn the wheel right unless I am rolling forward or backwards. It will turn full right on gravel or grass but not pavement. This was a case even before the box swap I was hopping the box would fix it.

Usually caused by the pressure relief valve being activated. It takes some higher pressure to turn the wheels with the "friction" of a paved surface. You should be able to turn on paved surfaces, before and after the swap.

the shop did not fully center the pitman arm I know because I get 2-3/4 turn left and 2-1/4 turn right and they can not get the steering wheel straight.

Due to the geometry of the steering system there sometimes are minor differences on the number of turns. You can double check to see if you are hitting the mechanical stops on the steering system. Easy to see with the wheels turned either direction. Your pitman may have been installed a little "off" It is IMPERATIVE that the TRW swap begins with the Sheppard steering gear being centered and the pitman arm installed with the TRW steering gear exactly in the center position.

they said an alinement would fix of course it did not.

Yet ANOTHER shop who uses that idea! NOT the solution!

The steering wheel centering fix is EASY. A knuckle located under the plastic cover under the steering wheel. It looks like a universal joint and has many splines and a grove all the way around for indexing the steering wheel to center. One bolt and 5 minutes it is centered. It took two tries to get it perfect on my coach but a simple procedure.

The shop now has it back to fix the index of the pitman arm.

any other suggestions on the pull (if not the index)?

and any idea on the unable to turn right?

I would make sure the steering gear poppets are set correctly. Under idle power only, turn the wheel right and left to the mechanical stops and hold it there for a few seconds. It has to be done in BOTH directions. This will allow the spring loaded poppets to "set" correctly to give you full range of steering, to the mechanical stops. You might have allow the coach to move during the process or take almost all the weight off the front tires with front jacks if you have them. I would double check that you are hitting the mechanical stops.

I hope this helps a little. Post here and I will check back later to see how the shop did centering your pitman arm. It is hard to chase after the fact.

Cheers and SWAP ON! (if you want too )

[CrazyKnight]

Originally Posted by YC1

After all the modifications possible I am no sitting at Josams having an alignment done.

Experimenting along the way I had it thoroughly botched up so needed to get it back in proper order.

Did the test drive and the impact hammers are working away. We are still inside the RV. Mike is our tech. Lots of tattos and a large fellow. Very very good customer service person.

The place is very busy.

Barry, and Josmas, know what they are doing when it comes to coaches. I would have taken my coach there if I was in need of an alignment. Josams is one of the few shops I would trust to do a TRW swap correctly and install any of the Monaco Watts gear. I helped train their techs on a few of the Monaco Watts installations.

Barry and the guys are great to work with and they know their stuff!

Cheers

[YC1]

Just finished the drive back from Orlando to our home which is about 40 miles. There was plenty of wind as usual.

The alignment took about an hour, and that included two test drives.

The tech Mike, was very helpful and explained what he was doing as my wife and I sat in the RV the whole time.

The steering effort I hoped to improve came back with the re-installation of shims. That is, it is much easier now.

I did not detect any pull either way. It tracked great and any adjustments do to gusts was instant and totally in control.

After this I am going to go back to tire pressures that are the same right and left side. The next trip won't be for a week or so and then will not be very long but it does not take much to tell if they pull.

I was able to let go of the wheel going down the road at 65 and it tracked perfectly.

Cheers

Note to anyone just picking up here. I have done all the mods possible. TRW, Watts Links, etc. And lots lots more.

My RV drove like a dream in the gusty winds and tight traffic on I4 today. It went precisely where it was pointed and stayed there with no drift or pull. : dance:

It only took 12 years to get this big of a grin on my face.

When it was brand new it was a terror to drive. And that is no exaggeration.

[Biljol]

Its ok I know your busy like the rest of us.

I am in PHX so going to FL for this is a bit out of the way.

The shop has the coach now to work on centering/Indexing the pitman arm.

I can turn and hit the stops on both sides my concern is not hitting the "Center high spot" when driving straight.

i guess now I need to think about the poppets if they have to reindex the pitman arms.

they did try to center the wheel but on one spline they were 1-2 inch right the other 1-2 inches left so the pitmen index should fix that ?

Originally Posted by CrazyKnight

Good day all,

From another forum emailed to me by my good friend Vanwill. Most of the problems, solutions, can be found in this thread but it is a long read. For those of you considering having a shop perform the TRW swap please read as much of the thread as you can. I have posted a few places that will help you avoid issues, and you will be armed with good information for the shop. Go as far as printing our one, or both, of the white papers graciously prepared by great wrench turners here on the forum.

From the email. I will bold the responses.


I posted this at Irv2 but have not had much luck.
Had a PM but my box was full. Let my supporter status lapse by accident.

I had done on my 2000 exe 40’

8 new air bags (tag bags were fine)

4 new front shocks

shepperd box replaced with trw from weller

A shop performed the TRW swap I assume?

my current issue is a pull to the right.

Another issue is involved.

I am also unable to turn the wheel right unless I am rolling forward or backwards. It will turn full right on gravel or grass but not pavement. This was a case even before the box swap I was hopping the box would fix it.

Usually caused by the pressure relief valve being activated. It takes some higher pressure to turn the wheels with the "friction" of a paved surface. You should be able to turn on paved surfaces, before and after the swap.

the shop did not fully center the pitman arm I know because I get 2-3/4 turn left and 2-1/4 turn right and they can not get the steering wheel straight.

Due to the geometry of the steering system there sometimes are minor differences on the number of turns. You can double check to see if you are hitting the mechanical stops on the steering system. Easy to see with the wheels turned either direction. Your pitman may have been installed a little "off" It is IMPERATIVE that the TRW swap begins with the Sheppard steering gear being centered and the pitman arm installed with the TRW steering gear exactly in the center position.

they said an alinement would fix of course it did not.

Yet ANOTHER shop who uses that idea! NOT the solution!

The steering wheel centering fix is EASY. A knuckle located under the plastic cover under the steering wheel. It looks like a universal joint and has many splines and a grove all the way around for indexing the steering wheel to center. One bolt and 5 minutes it is centered. It took two tries to get it perfect on my coach but a simple procedure.

The shop now has it back to fix the index of the pitman arm.

any other suggestions on the pull (if not the index)?

and any idea on the unable to turn right?

I would make sure the steering gear poppets are set correctly. Under idle power only, turn the wheel right and left to the mechanical stops and hold it there for a few seconds. It has to be done in BOTH directions. This will allow the spring loaded poppets to "set" correctly to give you full range of steering, to the mechanical stops. You might have allow the coach to move during the process or take almost all the weight off the front tires with front jacks if you have them. I would double check that you are hitting the mechanical stops.

I hope this helps a little. Post here and I will check back later to see how the shop did centering your pitman arm. It is hard to chase after the fact.

Cheers and SWAP ON! (if you want too )

[YC1]

The tech pulled my steering wheel to center it today. I had the center column off for easy access and it takes just one bolt to take it loose.

One large nut and a wheel puller. He said there was finer adjustment available there versus the shaft. Having disconnected the shaft I concur. Smaller splines for sure at that point.

The horn/plastic part just pulled of with a hard jerk and one wire to remove.

[CrazyKnight]

Originally Posted by YC1

The tech pulled my steering wheel to center it today. I had the center column off for easy access and it takes just one bolt to take it loose.

One large nut and a wheel puller. He said there was finer adjustment available there versus the shaft. Having disconnected the shaft I concur. Smaller splines for sure at that point.

The horn/plastic part just pulled of with a hard jerk and one wire to remove.

As long as the tech knows what he is doing. Josams does. I know of 2 clock springs ruined by shops who thought they new what they were doing. I always tell people about the easy way down near your ankles first. Generally gets center really close. The splines on my 2011 were really fine on the shaft near the floor. Snowflakes!

Myron, hope you all are doing well. We miss being on the road and seeing our friends.

Cheers

[CrazyKnight]

Originally Posted by Biljol

Its ok I know your busy like the rest of us.

I am in PHX so going to FL for this is a bit out of the way.

The shop has the coach now to work on centering/Indexing the pitman arm.

I can turn and hit the stops on both sides my concern is not hitting the "Center high spot" when driving straight.

i guess now I need to think about the poppets if they have to reindex the pitman arms.

they did try to center the wheel but on one spline they were 1-2 inch right the other 1-2 inches left so the pitmen index should fix that ?

That is the only thing I would make sure of when they finish. Wheels straight, even idle along to check and the TRW should look like the picture below.

Resetting the poppets is an easy procedure if they need to do that during the reset.

TRW Centered: Line on the output shaft points at the hump in the case. It DOES NOT matter where the pitman arm winds up on the shaft, indexed, as long as the wheels are straight ahead, tracks straight and the TRW shaft to case relationship looks like this. It will probably take a phone photo or mirror to see it when installed on the coach. Then you know you are getting the "high spot" on the TRW gear with little to no play during straight ahead driving.

Cheers

[Biljol]

The more I hear the more I think the pull is from something else.

I hope they can figure it out I did notice the coach leans a bit to the drivers side since the new air bags used to lean a bit to the passenger side could that cause the pull?

Wish I was someplace with some people that really know the coaches and can get it right.

Let’s see pull to the right and can’t turn right on hard surfaces could it be a king pin or bearings how about the tie rods?

I would assume they would look at all that during the alinement.

[YC1]

They checked all of that during the alignment on mine. I asked specifically about the ride height possibly effecting the "pull" and he said no, not possible.

However, being an airplane builder I know what a tiny bit of a difference can make in the handling of a vehicle (airplane that is).

It might be possible to have the rv canted slightly and the angle of attack to the relative wind could make it act like a giant rudder.

I'm not sure the tech had time to process that thought. What say you Craig? You are a plane builder too as I recall.

It sure would not take much to make the thing want to turn one direction or the other.

I have not checked my ride height in years but originally it was so far off I had to move the adjustment bars to get it to the proper height.

[CrazyKnight]

Originally Posted by YC1

They checked all of that during the alignment on mine. I asked specifically about the ride height possibly effecting the "pull" and he said no, not possible.

However, being an airplane builder I know what a tiny bit of a difference can make in the handling of a vehicle (airplane that is).

It might be possible to have the rv canted slightly and the angle of attack to the relative wind could make it act like a giant rudder.

I'm not sure the tech had time to process that thought. What say you Craig? You are a plane builder too as I recall.

It sure would not take much to make the thing want to turn one direction or the other.

I have not checked my ride height in years but originally it was so far off I had to move the adjustment bars to get it to the proper height.

Biljol

Yes, I would at least check ride height. It should have no affect on the pull but it will change the wind characteristics slightly. My ride height was also off by quite a bit when I purchased my coach.

This situation made me think of everything Van went through with his coach.
Vanwill, on the wandering thread, a very good friend of mine. We have turned many wrenches together and have been under so many coaches I have lost track. Van's coach, and a few others I am aware of, came with the axle "set" canted in the coach.

I would follow him and you could see the "dog walk" of his coach and it always had a slight pull to the curb side, if I remember correctly. I have test driven no less than 10 coaches after various improvements, TRW swap and full Monaco Watts set ups, and almost 1/2 had a very slight tendency to go to the curb when allowed to.

Vanwill went as far as making adjustable trailing arms and we tried a bunch of different set ups and I would follow him. We went as far I could see the entire side of his coach from behind as he tracked down the road. Never really found a "perfect" solution.

Myron, Yes I am an airplane builder RV-6. I have always wondered if some good old boy at HR, Monaco, used a rudder tab of sorts to preset a yaw in the coach.

Random coffee thoughts,

Cheers.....and SWAP ON!! (if you want too)

Craig

[Biljol]

So I had no pull with the shepherd box and now I do.

They did do air bags shocks at the same time.

My pull at highway speeds will get me onto the shoulder in less than 500 ft and I have to hold the wheel about 1.5 inch to the left to counter act it.

The shop is really thinking it’s the trw box but I just don’t know.