Question:
I recently bought two Cooper Roadmaster 14 ply tires and put them on my 32-foot Georgie Boy motorhome (front tires). I ran the prescribed 85 pounds of air pressure and they rode like a rock. I spent over $100 trying to get the bounce out of them, to no avail. Over 55 mph, they bounce up and down.

I then bought four new 12 plies for the back. Question is: Can I swap the 15 ply front tires for the two 12 plies on the back? And get a better ride and handling?  Thanks for your comments. I will be waiting on your answer.

--Jack in Dora, Alabama

Answer:
Hello Jack,

Thank you for the great question. We recommend weighing the coach to determine the correct tire for the load and also to determine the correct tire pressure.  The tire manufacturers publish tire inflation tables to show you the recommended pressure based on your load. It should be as close to normal to the maximum load you will carry. If you are not sure, add an extra 5 to 10 PSI for a safety margin.
  If the tires are not working well on front and are out of round, I would recommend taking them back to the dealer and getting another set of tires for the front. Chances are they will not work well on rear. You will not be able to rotate to the front later on without having problems again. On another note, make sure the tires are properly mounted and beads are correctly seated. Bottom line: I would not be in favor of mixing different tires on the rear, especially if they had problems on the front and I had a chance to return them.

Best wishes,
Robert Henderson

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Question:
Hi Robert,

Recently, I had my nimble 25- foot R-Vision Trail Lite Class A in the shop for tire balance, rotation and alignment.  The mechanic noticed left front tire really worn on inside edge and quickly diagnosed 3 ball joint failure as well as a bad Idler arm —driver side. He said there was a little side-to-side movement.  My first estimate for repairs is a whopping $1,850 for all four joints and the arm alone is $850!  I suspect the chassis was not greased at oil changes (previous owner—-and my fault too!) now at 35K miles.

Is it possible that a 2002 Chevy Workhorse chassis (5.7 L) idler arm be adjusted at some Bell Arm attachment rather than having to buy an $850 part replacement?  What is consequence for alignment afterwards?

Thank you!
Joe M.
Bloomington, Indiana

Answer:
Hello Joe,

Thank you for the excellent question.  I’ll see if I can give you a good answer.  It is rare for us to have to change ball joints on a P32 chassis motorhome, especially all four. Upper A-arm shafts are a much more common problem, as they greatly affect the alignment.  One of my main concerns for your vehicle would be ride height on the front end.  It should have from 1.75 to 2.5 inches from the rubber bump stop to the metal striker plate. When a P series motorhome such as yours loses ride height due to weak springs, blown air bags, and/or is heavily loaded without being realigned, this can cause the vehicle to have negative camber and have toe out alignment condition which will rapidly wear the inside of the driver’s side tire.

Also, the bell cranks (idler supports) tend to be a weak link due to their construction. They use bushings rather than bearings, and these bushings tend to become worn out within 5,000 miles.  This causes play in the steering and potential alignment change.  The SuperSteer design uses tapered roller bearings that can be preloaded to provide precise steering control over the life of the vehicle. 
SuperSteer also features a bell crank arm for the driver’s side, which uses tapered roller bearings for increased precision and durability.  Both of these parts feature a lifetime warranty, and the combined retail price of these parts is $624.39. 
Should your coach also need coil springs due to insufficient ride height, SuperSteer builds coil springs designed to match the weight of your vehicle without requiring airbags, due to their larger wire size.  These springs also provide greater stability and handling because of their higher spring rate. We recommend that your coach be weighed with a normal cruising weight to determine the correct spring.  Finally, be sure to have your vehicle realigned to Henderson’s Line-Up P32 specifications. You can find out more at supersteerparts.com or hendersonslineup.com or feel free to call John Henderson at (888) 898-3281 ext. 313 or e-mail him at john@supersteerparts.com.  I hope this provides you with the information you need.

Best wishes for safer and happier driving,
Robert Henderson


Do you have a question related to alignment, steering, handling, braking, fuel economy, tires, safety and maintenance of your RV? Robert Henderson, the president of Henderson’s Line-Up Brake and RV and SuperSteer/SuperStop products in Grants Pass, Oregon, is available to answer questions from readers. You may send your questions by e-mail to editor@rvlife.com.

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Question:
I have a 1996 Rexhall Aerbus 36-foot with a tag axle. I had the steering gear box changed and after that I have never had the brakes that it had before.

We have bled the brakes twice and the shop that did the change also bled the brakes. Is there something that we have over looked? The brakes feel like they still have air in them; the pedal is real soft but does not bled down. It has a separate master cylinder for the tag axle and that was bled for air in the system. We used DOT 4 fluid. Since then I have not used the motorhome much as I don’t trust the brakes.

—Ray Dean

Answer:
Hello Ray,
Some deal—to get your steering fixed and mess up your brakes!

I don't know which chassis you have. However, in either one of the brands (Ford or Chevy) Rexhall used the power steering pump to supply the boost for the hydraulic brake booster. My suspicion is that the hydraulic system has some air trapped in it. You can bleed the system by turning the wheels back and forth with the front end off the ground while applying some brake pressure.  If that does not work, you can use an air conditioning vacuum pump or the like attached to the power steering reservoir to draw some of the air out of the system while turning the steering wheel and applying brakes.

The Chevy chassis can be a very challenging system to get the air out of, especially with automatic parking brake. On some of them there is a bleeder screw underneath.

Best wises for Safer and Happier Driving!
Robert

Do you have a question related to alignment, steering, handling, braking, fuel economy, tires, safety and maintenance of your RV? Robert Henderson, the president of Henderson’s Line-Up Brake and RV and SuperSteer/SuperStop products in Grants Pass, Oregon, is available to answer questions from readers. You may send your questions by e-mail to editor@rvlife.com.

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Do you have a question related to alignment, steering, handling, braking, fuel economy, tires, safety and maintenance of your RV? Robert Henderson, the president of Henderson’s Line-Up Brake and RV and SuperSteer/SuperStop products in Grants Pass, Oregon, is available to answer questions from readers. You may send your questions by e-mail to editor@rvlife.com.

Question:
I have a 37 ft motor home with 19.5 tires on it I would like to know if 14 ply is over kill I want to be as safe as I can when it comes to my tires
 
Later gater...
Lou Renville


Answer:
Hello Lou,
 
Typically when it comes to tires it is better to be safe than sorry–especially on a heavily loaded vehicle like an RV.  However, before I spent the money for  a 14 ply tire, I would want to weigh my rig and see how much load I was actually carrying per tire.  If you are only carrying 3,000 per tire,  you  won’t need the extra capacity.  
If you have the 8R 19.5 tires on the coach now, I would recommend going to the lower profile, wider 225/70 19.5  tire for better handling and load carrying capability at  lower tire pressure. This will improve both ride and handling.
 
Another factor to consider is your wheels. They may be only rated for 95 lbs of pressure. Bottom line: It won’t hurt but it may not be necessary. Hope this helps.
 
Best wishes for Safer & Happier Driving. —Robert

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Do you have a question related to alignment, steering, handling, braking, fuel economy, tires, safety and maintenance of your RV? Robert Henderson, the president of Henderson’s Line-Up Brake and RV and SuperSteer/SuperStop products in Grants Pass, Oregon, is available to answer questions from readers. You may send your questions by e-mail to editor@rvlife.com.

Question:
I plan to add tire pressure monitors to my rv wheels but need to turn the valve extenders on the outer wheels on the rear axle. I think that simply loosening the retaining nut, turn and retighten should do. But is it OK to do under normal pressure -100 psi?

Will this damage any washer causing a leak or..........?

Tx Dennis S. Peacock

PS do you have a recommendation for a monitor unit?

Answer:
Hello Dennis,
 
I believe you should be able to loosen and rotate valve stems without hurting anything as long as you have no sticky or damaged parts . Try loosening and rotating  the stem the direction you need it to go. Check for leaks after you install monitors by spraying a soapy water solution around the attaching points on the stems and pressure monitors.  A real common one we have sold is the Pressure Pro brand .  To install simply remove the valve caps and screw the new monitors on. It will give you a pressure only reading.
 
There is another brand on the market  that goes inside your tires and is mounted  with a big stainless steel band to attach  around the wheels.  It measures temperature as well as pressure.    
Here is the info on  the SmarTire System:

Sensors mounted on each wheel measure tire pressure and temperature every 12 seconds and wirelessly transmit tire data every three to five minutes to a receiver mounted on the vehicle.

The receiver then processes the data transmissions and compares them to pre-programmed settings to determine if a tire is under-inflated. The SmarTire RV receiver can monitor up to 20 wheel positions and is able to handle RVs of any length and tow-behind vehicles.

At the push of a button, real-time tire pressure and temperature information is then available to the driver via a dash mounted display. If the system detects a tire that is operating under-inflated or extremely hot, the system automatically warns the driver to the condition before it becomes dangerous.

Here is the install info I can share with you on the SmarTire as well.  
Those monitoring tires on an RV or towing a large trailer with a SmarTire system will have an advanced installation.
·  First, have your local tire professional remove your tires from your wheels. ·  Then you or your installer will install the wireless sensors on your wheels using the included mounting straps. ·  Next you will need to run one or more external antennas under your vehicle for extended wireless range. The antennas mount magnetically so no drilling or bolting-on is required. ·  The SmarTire receiver or display is as easy to install as a radar detector; just choose a spot to mount it and then hardwire it to a switched power circuit in your vehicle.

There are other companies as well besides these and I will be looking into them soon, however I wanted to get back to you now.

Best wishes and  Safer & Happy Driving,
—Robert

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Do you have a question related to alignment, steering, handling, braking, fuel economy, tires, safety and maintenance of your RV? Robert Henderson, the president of Henderson’s Line-Up Brake and RV and SuperSteer/SuperStop products in Grants Pass, Oregon, is available to answer questions from readers. You may send your questions by e-mail to editor@rvlife.com.

Question:
I have had handling problems with my Great West Van RV from the first day I bought it second hand. Firstly the drivers side torsion bar arm was not installed properly, nuts were on the wrong side of the washers and therefore pulled through. Secondly the tire pressure was only 32 psi on 15 inch tires.Thirdly the shock absorbers are Monroe gas-matic. Also the leaf springs were at their old age( 22 years old) and needed help.
Solutions: I replaced the torsion bar arm. I replaced the tires and rims with 16-inch rims and heavy duty tires at 50 psi. Two new leaf springs were added to each side to bring the back end up 1 inch and level with the front.

I am contemplating replaceing the Monroe shocks with Bilstein shocks. These camperized vans were only designed as vans and were top heavy and often overweight and under designed for handling at highway speeds. Will new shocks increase the handling and increase the ride and comfort of this 6400 kgm van?

Regards,
Tom Gray

Answer:
Hello Tom,

It sounds like you have made some positive changes. The 16" wheels allows a much greater selection of tires including a full steel casing.  They have better load carrying and handling characteristics than a polyester sidewall, which will rot before the tread wears out on a
vehicle that does not get driven a lot.  I would recommend installing sway bars as well to reduce sway.  If you have bars already, you may be able to Increase the bar's diameter to reduce sway.

You don't say what chassis your coach is built on. You mention the springs need help. If springs are weak or overloaded that will also cause sway.  Are they coil springs?  If so, I believe you may be calling the radius rod or strut rod the torsion arm. If that's the case, it may be Dodge or Ford twin I beam suspension. How much does it weigh, front axle vs. rear axle?  What is the factory GVW front and rear? I am assuming that this a Class B type vehicle (van conversion).

You may want to come down for a Road Performance Assessment at Henderson's Line-Up or at one of our authorized centers. I will look forward to finding out a little more about your rig.

Wishing you Safer & Happier Driving! —Robert

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Do you have a question related to alignment, steering, handling, braking, fuel economy, tires, safety and maintenance of your RV? Robert Henderson, the president of Henderson’s Line-Up Brake and RV and SuperSteer/SuperStop products in Grants Pass, Oregon, is available to answer questions from readers. You may send your questions by e-mail to editor@rvlife.com.

Question:
"My 28-foot Ford E-350 Class C motorhome is constantly warping the front rotors. What can I do to eliminate this problem? The rear drums hold up just fine."

Ron
Lynnwood, Washington

Answer:
Thank you for the excellent question.  This is a problem we run into quite frequently. I’ll list a couple points that contribute to this problem.

1. Disc brakes are more susceptible to vibration because of the clamping forces generated in a disc bake. It transfers into the steering wheel even if warped as little as three- to five-thousandths of an inch. A drum brake may be 20 to 40 thousands out of round and a person may not notice due to its design.  

2. The larger piston volume of a disc brake causes fluid to push back against the fluid in the caliper. This in turn causes the pedal to pulsate.

3. If the rear brake shoes are not as aggressive in holding back the weight of the coach, it puts more load on the front brakes. When getting a brake job done on a vehicle that has drums on the rear and disc up front, it is often a good idea to replace the rear brakes as well, because the rear brakes may be getting hard and glazed over. This causes them to lose their coefficient of friction.

4. I don’t know what year your coach is but the earlier Fords had a load-sensing valve that restricted fluid flow to the rear brakes on the vehicle. The idea is that if the vehicle is heavily loaded it will sit low in the rear, thereby opening up the flow through the load-sensing valve. This is all well and good until someone puts on airbags or overloads to raise the rear of the vehicle up. We used to disable the load-sensing valves to get full pressure to the rear brakes.

5. If you have the earlier rear anti brake skid system (or RABS for short) used by Ford in the early ‘90s, I have noticed some of the same problems with them as well. There is not a recommended way to disable the rear brake antiskid on these vehicles.

6. Every time you turn a disc brake rotor it has less material to dissipate the heat, thereby increasing the tendency to warp once again. You have to pay close attention to the minimum machine to tolerances. I would recommend replacing the rotor once you get close to the minimum machine to spec, not just the discard spec on the rotor. It takes knowledge of both of those numbers.

7. Cheap rotors may warp sooner than a quality well cast rotor. We use the Performance Friction rotors wherever possible. They offer better cooling and better metallurgy than many rotors on the market. I hope this helps. God bless you.
Robert Henderson, president of Henderson’s Line-Up, Brake and RV and SuperSteer/SuperStop products of Grants Pass, Oregon, regularly answers questions on RV steering, braking, handling, fuel economy, tires, safety and maintenance online at the Chassis Solution blog at rvlife.com.  Send questions by e-mail to editor@rvlife.com.

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Do you have a question related to alignment, steering, handling, braking, fuel economy, tires, safety and maintenance of your RV? Robert Henderson, the president of Henderson’s Line-Up Brake and RV and SuperSteer/SuperStop products in Grants Pass, Oregon, is available to answer questions from readers. You may send your questions by e-mail to editor@rvlife.com.

Question:
Robert,

How often should the wheel bearings be repacked on a class A motorhome or any motorhome? Does it make any difference if it is a class A or class C and does the chassis type make any difference?

Thanks!
Jim Tibbles

Answer:
Hey Jim,
It depends on the type of hubs that are being used.  Most Class C motorhomes have grease-type bearings that run hotter than an oil type bearing hubs.  On some class A motorhomes, you upgrade to an oil seal and run 80-90 weight gear oil in them. It eliminates the frequent packing (most grease hubs require 15 to 25 K service per manufacturer instructions). Oil-filled hubs can run an easy 50 to 100 k without service, provided you keep the oil at the proper level and don’t overheat or otherwise contaminate the fluid.  The wheel bearing adjustment is critical on an oil hub because the oil can leak by a seal if the Adjustment gets loose. We always use  full synthetic Amsoil in the hubs. Hope that helps.

Robert Henderson, president of Henderson’s Line-Up, Brake and RV and SuperSteer/SuperStop products of Grants Pass, Oregon, regularly answers questions on RV steering, braking, handling, fuel economy, tires, safety and maintenance online at the Chassis Solution blog at rvlife.com.  Send questions by e-mail to editor@rvlife.com.

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Question:
Dear Robert,
I have a 2008 Holiday Rambler Admiral with, 6,000 miles on it.  How often should I consider front end alignment? I have a Workhorse chassis, gas engine. And do I have to consider any particular maintenance of tires, rotation, etc.?

Thanks,
Barry L. Young
Madisonville, KY

Hello Barry,
We usually recommend that a straight front axle coach like this one gets aligned when it is new, and then once every 30,000 miles after that. Why do it when it’s new? For one thing, these alignments are done en masse at the factory, so it may not be that accurate. Also, the coach is unloaded the first time it is aligned, and now it’s loaded. We recommend that you always have a coach aligned in its normal, loaded, road-ready condition.

Do you have a question related to alignment, steering, handling, braking, fuel economy, tires, safety and maintenance of your RV? Robert Henderson, the president of Henderson’s Line-Up Brake and RV and SuperSteer/SuperStop products in Grants Pass, Oregon, is available to answer questions from readers. You may send your questions by e-mail to editor@rvlife.com.

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Question:
Dear Robert,  
We have a 2009 Winnebago View 24H, 16-inch rims. I understand how important checking the tire air pressure is. However, the valve stems are nearly out of reach. Just getting the valve caps off and on is a major task. I discovered that Camping World sells extenders. The front wheels valve stems are reachable, however, the rear duals are not. A 2-inch extender for the inside valves and a C-shaped extender for the outside valves looks like it would allow reach. What is your advice on mounting the extenders, and do you have any guidance about how to work with short valve stems?
 
Albert Franklin
Tacoma, Washington

Answer:
I know the frustration it creates when you can’t check the air pressure on your tires. This problem is usually related to the stainless steel wheel liners that make the hole used to access the valve even smaller.  The solid steel extenders and/or solid steel stems are my favorite way to deal it. You may opt for the stainless steel hoses that are available, however, you must be very careful to maintain the air pressure religiously. We have seen more than one inner dual that was flat because the steel hose had come loose and the tire lost air. The long, curved full steel stems we have used were made by Borg, and the tire had to be dismounted.  Definitely more work, but we don’t have to worry about them coming loose if they are properly installed.  Correct tire pressure really is an important issue, and there are some options to help you make sure this is maintained, such as tire pressure monitors or the Crossfire inner-to-outer dual wheel pressure equalizers. Do you have a question related to alignment, steering, handling, braking, fuel economy, tires, safety and maintenance of your RV? Robert Henderson, the president of Henderson’s Line-Up Brake and RV and SuperSteer/SuperStop products in Grants Pass, Oregon, is available to answer questions from readers. You may send your questions by e-mail to editor@rvlife.com.

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