Workhorse chassis steering issues

[Knightly]

I have a 2007 Itasca, 35' m/h on a W24 chassis. I consistently have steering problems. The unit tends to wander slowly from side to side. I have to constantly correct. I recently had the front end aligned and everything was fine.

My question: does anybody have any experience with add-on steering devices? If so, do they/it really work?

Knightly

[DriVer]

Quote:

Originally Posted by Knightly My question: does anybody have any experience with add-on steering devices? If so, do they/it really work?

Do you have the results of the front end alignment? (printout) Let's rule out what we know first before opening the wallet. Critical are weights & loading, air pressure, and perhaps tire wear. Check all the easy stuff first.

[Full-Timers]

Yes, too heavy in the back can cause that.

[paz]

As DriVer says, the first thing to check are alignment and tire pressures. Get the rig weighed - all 4 corners if possible, but at least front and rear axles separately.

As Full-Timers points out, a heavy back end can cause wandering. Most gas coaches have a long rear overhang, and that can lead to a problem with the tail wagging the dog.

We had the same problem with wandering on our motorhome on a W24. I ended up installing a Henderson rear track bar, and that made a huge improvement. The track bar keeps the rear axle more stable and reduces side to side movement.

[Wayneey]

Along with a set of Koni shocks I had a Safe-T-Plus installed at Brazel's this past June so far, I'm very pleased with these additions. For the record, soon after taking initial delivery of the coach I had it weighed, tire pressure adjusted, and an alignment done at Redlands. All numbers were within specs.

According to Workhorse, the 2007 W-24 chassis (and probably the W-20's and W-22's also although I don't know this for a fact) had a newly designed power steering system to address a noisy power steering pump and increase the end-to-end power assist. The result is power steering with a lot of assist at the expense of little to no road feel/feedback and, at least in my opinion, requiring almost constant steering correction.

The Safe-T-Plus keeps the steering wheel 'quiet' such that I can take my hands off the steering wheel and the coach will continue to track. No way could I have done that before. And of course, there's the added safety factor in the event of a blow out. Combined with the increased comfort provided by the Koni shocks, I'm experiencing some way improved driving.

A rear track bar is something I'm also considering but for the present I'm okay. Tiffin extended the wheel base by about 12"-15" inches which provides good highway stability; I'm not pushed around by passing over-the-road rigs although I can feel just a tiny wiggle in the rear end when a big rig invades my "air space" as it begins to pass.

Wayne

[Knightly]

Thanks to all responses. I will attempt to answer all the questions collectively.

Yes, I had the front wheels aligned July 22, 10. The total Toe(L +R) was -0.07 degrees, reset to 0.10, which is within specified range of 0.05 to 0.15 degrees. Rear axle thrust angle, 0.29 & 0.32 was outside of the specified Range of -0.08 to 0.08, however is NON ADJUSTABLE. The alignment fellow said that the rear differential wasn't out enough to make a difference. I have not noticed any difference in the tire wear before or since the alignment. Both front tires appear to be wearing very even.

I had the rig weighed and the R Frt was 3600 lbs., L Frt was 3350, RR was 7650, LR was 7300. So the RH side of the rig is 600 lbs. heavier than the left side. I was told to inflate both tires based on the heaviest side, ie: 3600lbs. for the front tires & 7650 lbs for the rear duals. The recommended tire pressures for my 235/80R22.5 LRG tires are: Frt 75 lbs., Rear 95 lbs. I did change the front to 85 psi when I noticed the outside tread was wearing faster then in the middle. Since I changed the pressure, I have driven 10,000 miles and the front tires are much more even.

The weights quoted are road ready weights, motorhome is loaded with our personal effects, fuel tank full, propane tank full, water tank 1/3rd., etc. Our gross weight was 21,900 lbs., well under the 24,000 lb max.

Thanks for your suggestions.

Knightly,
2007 Itasca 35' Sunrise, Blue Ox 10,000 lb. tow bar. Brake Buddy, Toad: 2007 HHR Chevrolet.

[Ding-a-ling]

What was the Caster reading? Sounds similar to what I had.
I had to have 3° of shim put in the front axle to correct a problem. Why it was that far off when delivered from the factory I never found out.

FJF

[dieselclacker]

Knightly,
There are some here on this forum, me for one, who have cured or greatly improved the problem you are having by increasing the caster setting on the front axle, and increasing the total toe in setting. Shims are available for setting the caster, you should aim for around 5 degrees positive angle, and match settings as evenly as possible from side to side. I have found that increasing the total toe in setting to 3/16 inch is a big help in curing the wandering you are experiencing. These settings will not cause the front tires to wear. If you can afford one, a rear track bar as mentioned by paz above, should be considered also.

Dieselclacker

[wa8yxm]

1: Tire pressure.. Have it weighed http://www.rvsafety.com and see what they say.

2: Alignment

3: Modifications..
3A: Trac Bars...
3B: Steering stabilizer
3C: Sway bars

Now the workhorse I have has a very good sway bar on it factory so I have not made any changes there.. "Sway" is side to side rocking where the motor home TIPS right or left.. When it does this you tend to compensate by turning the wheel,,, This makes it worse.

Trac Bars.. Another thing that a motor home can do is "Twist" on the axle.. this is side to side movement, it does not tip but the body and the frame are no longer pointed the same way.. TRAC bars also called Pan Hard bars "lock" the body in position over the axles so this does not happen.... I very highly recommend them.. Check out the ULTRA POWER Trac bar from Brazills if I've not mispelled it or Redlands.

Steering stablizers.. Yes, the steering on the workhorse feels sloppy.. I'm not sure if it really is or not (Have not broken out tools and measured it) but the addition of a steering stablizer.. Mine is the Blue Ox Tru-Center. Though some folks do not like that one... Seems to improve this...

I know that this summer my Tru-Center was in the shop... And it made a big difference in how the house handled.

[FreshAir]

Quote:

Originally Posted by Ding-a-ling What was the Caster reading? Sounds similar to what I had. I had to have 3° of shim put in the front axle to correct a problem. Why it was that far off when delivered from the factory I never found out. FJF

In 05 and maybe still to this day the WH factory setting for caster was, as I recall, about 3 degrees. I'm sure they had their reasons. When I had my caster changed on the recomendation of an alignment shop in late 2005, some alignment shops were aware of the caster thing and already had prior authorization from WH to make the change to apx. 5 deg.
Pat

[Knightly]

LF axle caster is set at 3.0 degrees. RF axle caster is set at 3.5 degrees. (specified range for both axles is between 2.9 to 4.9 degrees according to the alignment shop).
I will enquiry about changing the caster to 5 degrees when I get home in a couple of weeks. It sounds like there are several options. The only problem is the cost associated with all the modifications.

Thanks, Knightly

[DriVer]

Quote:

Originally Posted by Knightly The only problem is the cost associated with all the modifications.

You will probably require the motorhome to be setup on the front end machine again. The task therefore would be to R&R (or loosen) the front spring U-Bolts because some shops may want to replace those. Wedges will be placed between the axle and the spring that will change the caster angle. Re-torque the U bolts to spec. (not to exceed 5°) Verify the caster angle on the machine and get a printout. Test drive the vehicle. Don't let anyone suggest that the axle needs to be bent.

[jojolou]

I had the same problem, after having a front alignment, I had the Safety-Plus and a Roadmaster front track bar installed. The difference was like night and day!

[krf9113]

I have a 2008 Safari Simba 8.1 GM on a W22 chassis. The handling was terrible. I've had other motorhomes so I know how it should handle.
I installed the Safe-T-Plus, it made the handling worse. I contacted Wayne at Roadmaster and explained the situation. He told me that my assumption was accurate. The Safe-T-Plus while it has it's merits when it comes to emergency handling for the W22. However, installed the W22 chassis it can make the handling worse.
We agreed to meet in Quartzite. The Davis TruTrac bar was installed. Just like night and day. I drove back to Phoenix fighting a north cross wind all the way and the coach handled like a dream.
I did leave the Safe-T-Plus on because it just added another safety factor.
Next on the list are the Koni shocks. Which should correct most everything that should have been on the coach when it left the factory.