More Workhorse Handling Issues!!!

[fishmaine]

Hi dieselclacker......

Thanks very much for your follow-up......perhaps my expectations are a bit too high. And perhaps more people are dealing with these steering issues but just accepting (or expecting) them as part of what happens when you drive a big breadbox across the prairie in fairly high wind!

I am running a bit higher air pressure in front (85) and back (95) on my 19.5 tires....will double check those pressure calcs. as I know that can effect drivability also.

It is a bit of a shame as this motorhome is heaven to stay once parked. Also the motor runs perfectly after I installed new spark plugs and spark plug wires. Also the motor is very peppy as a fairly large motor is installed in a fairly little (light) RV...this surprises the wife driving behind me and trying to keep up!

One final thought for those anticipating adding handling modifications....just installed the front sway bar relatively recently (this year)....and the handling (particularly sway) seems to be no better (and may be even worse) than just having the rear sway bar only (which I installed last year)......in other words I am confirming that the rear sway bar is (in my opinion) by far the more important bar to install than the front.

Hopefully correcting toe-in and caster next week will be of great help!

[CamJam1]

Please let us know how it goes for you after caster adjustment. The Roadmaster Reflex steering stabilizer (which apparently you already have) fixed most of my problems. Also check for loose front wheel bearings-- easy check if you have leveling jacks-- and tie rods. If caster doesn't fix it I'm betting something is worn. My front wheel bearings were loose with only 15k miles on the coach.

[Harvard]

The symptom of having too little caster is "loose steering".

Loose steering is where you have a dead "do nothing" zone between left and right.

Here is a link to my experience, circa 2010:

E350/E450 Handling Problems are caused by too little + CASTER

[fishmaine]

Hi CamJam - Thanks for your note....will advise when corrections are completed which will be sometime next week. Hopefully this will correct my problems or at least greatly reduce them. Will be sure to ask them to check wheel bearings and tie rods (and the rest of the front end). Thanks again.

Hi Harvard - Have reviewed your link in detail. VERY interesting. I am now feeling quite convinced that I may have finally stumbled onto a possible solution to my steering problems...namely adjusting the caster (as far positive as possible, I believe). I am having an alignment shop locally (in Tucson) do the alignment. They have suggested that if they need any special parts they are readily available locally nearby. When reviewing your post it looks like the caster shims you used were perhaps a bit special....were they readily available or a special order? My shims look like those in the attached photo (thanks to GREGORYJ for the photo). Any idea if special shims would be needed for a workhorse chassis (W-22)....I know yours is/was a Ford chassis. Any thoughts would be appreciated. Also your take on a slight toe-in possibly needed on both front wheels would be appreciated (and if so, amount in inches?). Assuming Ford steering issues are abt. the same as Workhorse steering issues.

[Harvard]

The parts (wedge shims) required to adjust the caster on a solid axel are common and are readily available.


I set my toe to be about 1/16 to 1/8 inch using a tape measure so I would expect better accuracy from an alignment machine.

The art of knowing the symptoms of too little caster has been, for the most part, a lost art. The modern alignment rack has replaced the art with artificial intelligence that has never been trained well enough when it comes to interpreting a "caster range" as opposed to a "caster specification". Caster is not meant to be a "put it in the middle of the specification" but the computer does just that. IMO

[fishmaine]

Hi Harvard......Thanks for your further thoughts....will advise all of the results when the job is completed........

[fishmaine]

Just returned from the alignment shop. They began by giving the motorhome a thorough inspection for damaged components. The short story is that no problems were found with the wheel bearings, steering linkage, steering box, or other components like the drag link, tie rod joints, tires, shocks, springs or stabilizer shaft. Also the alignment was within spec with the exception that it was toed-in a bit further than optimal (see alignment readings below).

At the completion of the alignment and castor increase, a 60 mile drive was made in very light wind (0-10 mph) and the handling was outstanding. The handling was much more responsive and much less prone to wander (also less wander on uneven surfaces). I could pass comfortably without anxiety. The play in the steering wheel was only occasionally about ¼ to ½ inch up or down (on the steering wheel) intermittently v.s. previously it was up to 1 inch up or down constantly (and sometimes up to 1 ½ to 2 inches constantly). The steering still had bit of a “light” feeling (I am still about 600 lbs light on the front end) but the constant wheel wander (that is, the motorhome has a mind of it’s own…driving itself) was pretty much gone.

The other day I was also able to drive the motorhome in heavy wind (8-20 mph with occasional gusts over 20). The handling was also much improved in this case. Side wind seemed to be less of a problem than headwind…particularly hitting the front at an angle (directly head-on was less of a problem). Steering was looser (as expected) but no where near what it was before the caster changes were done (vastly better). Instead of the constant up and down of the steering wheel that was the case before the changes, the whole motorhome seemed to be gently pushed to the left or right (without the constant steering wheel corrections….although corrections of 1/2 to 3/4 inch were made occassionally).

SUMMARY STATEMENTS (and opinions):

1) It is well worth making the castor changes. I have much greater control of the motorhome.

2) I believe very, very, short class A motorhomes (mine is 30.5 feet long, 12 feet high, on the workhorse chassis) will always be a challenge to drive in high winds (gusting greater than 20 mph) even with every conceivable handling device installed.

3) If you have to drive in consistently high winds I believe a 5th wheel is the better answer (I drove one for 150,000 miles over 15 years)....or perhaps a 45 foot long tandem diesel pusher.

4) With appropriate corrections, short class A motorhomes can be driven safely, but not necessarily comfortably in high winds. This is because, I believe, modern motorhomes are very wide which doesn’t leave much leeway to stay in your lane when you are being pushed around.

5) And finally, obviously it is best to avoid driving in high winds if possible!

The alignment readings before and after were as follows:

Caster:
Left 6.5 after, 3.0 before
Right 6.7 after, 3.0 before

Toe -In:
0.08 after, 0.13 before

Camber:
left 0.7 after, 0.3 before
right 0.6 after, 0.2 before

(Note: although camber is technically non-adjustable with the W-22 workhorse chassis, the alignment techs said it was slightly changed when the caster shims were added…which they claim actually will help handling)

Costs for all the changes made were around $800 overall with parts at about $300 and labor about $500.

Some of my costs will not be applicable in many other situations. First, I had a Roadmaster steering stabilizer installed a few years ago (the RM frame bracket is about ¼ inch thick and attaches to the bottom of the drivers side I-beam U-bolts and then to the steering stabilizer). Second, I also had very thick 4 degree castor wedges installed. Thus, I had to replace all 4 of my U-bolts with longer U-bolts so that there would be adequate thread protruding beneath each U-bolt nut (a safety issue). Therefore a cost that may not be applicable to other motorhomes would be the cost of changing out their U-bolts which was approx. $120-$150.

The other parts needed were 2, 4-degree wedges (they were aluminum) and 2 new longer center bolts with a 1 inch head, which were necessary due to the extra thick wedges installed.

Also of the total costs above, $201 of it was for the actual final alignment.

The business doing the work for me was ACCU-TRAC LLC, located on the SE side of Tucson AZ. The business is just a few minutes from the Pima Fair Grounds where many RV rallies are held. I would highly recommend them as I feel they were both honest and with their pricing, and kept me educated and informed during the whole process. David is the owner and contact.

[Unplanned Tourist]

Glad to hear you are happy Fishmain.

I keep telling people to add caster first thing they do to help, but everyone seems to buy into all the other hocus pocus that's out there.

[Harvard]

Thank you Fishmaine for your follow up post.

I am sure you will find your next return trip (AZ to Maine) much more relaxing. Safe travels.

[CamJam1]

Thanks for the update, fishmaine.

Do you still have the Reflex steering stabilizer on your rig?

I'm happy with mine now but I'd still like to add more caster sometime. The big problem I have here is that there are no alignment shops nearby who work on RVs.

[Unplanned Tourist]

Originally Posted by CamJam1

Thanks for the update, fishmaine.

Do you still have the Reflex steering stabilizer on your rig?

I'm happy with mine now but I'd still like to add more caster sometime. The big problem I have here is that there are no alignment shops nearby who work on RVs.

If you are up to it, you can do it yourself. Just get a set of shims and put them in. Thick end to the back!

Ebay has them in different degrees. I would try the 4 degree ones first.

With your solid front axel, the toe won't change, but you may need longer U-bolts.

https://www.ebay.com/itm/Belltech-4-....c100008.m2219

[yeloduster]

Originally Posted by Mark_K5LXP

When I got my P32 the PO had already installed the supersteer bellcrank and I'm guessing because the steering must've been worse than it is now. Mine wanders a bit but nothing like what you describe. Considering this is a fairly inexpensive bolt-on widget it might be worth a try before you go mucking with wheel geometries. Even if it's not a magic bullet at least you will have one less variable.

Mark B.
Albuquerque, NM

Hello Mark,

Thank for you contribution to this thread. However.

You have a Workhorse P32 chassis with independent front suspension. It has bellcranks.

The OP has a Workhorse W22 with a solid front axle suspension. It does not have any bellcranks to change.

[yeloduster]

Originally Posted by fishmaine

Just returned from the alignment shop. They began by giving the motorhome a thorough inspection for damaged components. The short story is that no problems were found with the wheel bearings, steering linkage, steering box, or other components like the drag link, tie rod joints, tires, shocks, springs or stabilizer shaft. Also the alignment was within spec with the exception that it was toed-in a bit further than optimal (see alignment readings below).

At the completion of the alignment and castor increase, a 60 mile drive was made in very light wind (0-10 mph) and the handling was outstanding. The handling was much more responsive and much less prone to wander (also less wander on uneven surfaces). I could pass comfortably without anxiety. The play in the steering wheel was only occasionally about ¼ to ½ inch up or down (on the steering wheel) intermittently v.s. previously it was up to 1 inch up or down constantly (and sometimes up to 1 ½ to 2 inches constantly). The steering still had bit of a “light” feeling (I am still about 600 lbs light on the front end) but the constant wheel wander (that is, the motorhome has a mind of it’s own…driving itself) was pretty much gone.

The other day I was also able to drive the motorhome in heavy wind (8-20 mph with occasional gusts over 20). The handling was also much improved in this case. Side wind seemed to be less of a problem than headwind…particularly hitting the front at an angle (directly head-on was less of a problem). Steering was looser (as expected) but no where near what it was before the caster changes were done (vastly better). Instead of the constant up and down of the steering wheel that was the case before the changes, the whole motorhome seemed to be gently pushed to the left or right (without the constant steering wheel corrections….although corrections of 1/2 to 3/4 inch were made occassionally).

SUMMARY STATEMENTS (and opinions):

1) It is well worth making the castor changes. I have much greater control of the motorhome.

2) I believe very, very, short class A motorhomes (mine is 30.5 feet long, 12 feet high, on the workhorse chassis) will always be a challenge to drive in high winds (gusting greater than 20 mph) even with every conceivable handling device installed.

3) If you have to drive in consistently high winds I believe a 5th wheel is the better answer (I drove one for 150,000 miles over 15 years)....or perhaps a 45 foot long tandem diesel pusher.

4) With appropriate corrections, short class A motorhomes can be driven safely, but not necessarily comfortably in high winds. This is because, I believe, modern motorhomes are very wide which doesn’t leave much leeway to stay in your lane when you are being pushed around.

5) And finally, obviously it is best to avoid driving in high winds if possible!

The alignment readings before and after were as follows:

Caster:
Left 6.5 after, 3.0 before
Right 6.7 after, 3.0 before

Toe -In:
0.08 after, 0.13 before

Camber:
left 0.7 after, 0.3 before
right 0.6 after, 0.2 before

(Note: although camber is technically non-adjustable with the W-22 workhorse chassis, the alignment techs said it was slightly changed when the caster shims were added…which they claim actually will help handling)

Costs for all the changes made were around $800 overall with parts at about $300 and labor about $500.

Some of my costs will not be applicable in many other situations. First, I had a Roadmaster steering stabilizer installed a few years ago (the RM frame bracket is about ¼ inch thick and attaches to the bottom of the drivers side I-beam U-bolts and then to the steering stabilizer). Second, I also had very thick 4 degree castor wedges installed. Thus, I had to replace all 4 of my U-bolts with longer U-bolts so that there would be adequate thread protruding beneath each U-bolt nut (a safety issue). Therefore a cost that may not be applicable to other motorhomes would be the cost of changing out their U-bolts which was approx. $120-$150.

The other parts needed were 2, 4-degree wedges (they were aluminum) and 2 new longer center bolts with a 1 inch head, which were necessary due to the extra thick wedges installed.

Also of the total costs above, $201 of it was for the actual final alignment.

The business doing the work for me was ACCU-TRAC LLC, located on the SE side of Tucson AZ. The business is just a few minutes from the Pima Fair Grounds where many RV rallies are held. I would highly recommend them as I feel they were both honest and with their pricing, and kept me educated and informed during the whole process. David is the owner and contact.

I read your report with interest. I knew that a 4° wedge didn't actually add 4°. It is interesting to note a 4° wedge adds something like 3.5°-3.6°.

I plan on investigating the feasibility of adjusting my own caster next spring and your information is very valuable to me.

I'm still trying to wrap my mind around how changing caster on a solid axle changes camber!? If the axle is machined with the kingpin bores at 0° relative to the axle spring pads then when the weight of the vehicle is placed on the springs pads it will cause a bend in the axle that would create positive caster equal to the axle deflection. However, it seems to me that the camber angle caused by this deflection shouldn't be affected by the caster wedges! Just thinking! I think I'm missing something!

It would be interesting to know what the repeatability of the alignment shops measurements are. Additionally, how much real world difference does .4° camber make?

I reported in an earlier post that adding the rear sumo springs induced a little bit of oversteer in my W22 chassis. The rear track bar helped that situation but I think if I had ≈6.7° positive caster I could mitigate that even further!

[Harvard]

Yeloduster said:
I"'m still trying to wrap my mind around how changing caster on a solid axle changes camber!?"

The change in camber is real but too miniscule (0.4*) for all practical purposes. IMO.