Tire clearance issue

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Tire clearance issue

March 15, 2013, 07:35:07 pm

It appears that the previous owner at some point tried to drive the Coach a short distance with the left rear suspension down. This is the damage above the LR tire -- that tomorrow I'm tackling with some fiberglass mat and cloth. The other side has only some light scuffing.

All the more reason I've decided to have eight of those square tubing chassis stops with U-bolts made-up and fitted before I'm even driving this thing anywhere

Re: Tire clearance issue

Reply #1 – March 15, 2013, 07:40:41 pm

Sadly, that little scuff is not uncommon. As long as it doesn't go all of the way through allowing road spray to get in, it really doesn't hurt anything but since you can see the blue foam speeking through, I must agree with the fiberglass repair. Make sure you use a resin that will not melt the foam, epoxy if you can. Be careful with polyester resin. Test a small area first.

Re: Tire clearance issue

Reply #2 – March 15, 2013, 07:45:29 pm

It may not have been driving with low air but if the road is rough and off kilter you can catch the Fiberglass with the tire at speed. This is up until 2002 when they raised the coach 2 inches to prevent it.

Re: Tire clearance issue

Reply #3 – March 15, 2013, 08:06:11 pm

Mine had that happen and the PO put a 12 sq piece of fiblreglass panel over the hole and a few very fine screws to hold in place after covering area with a caulking. I agree that the chassis stops are the culprit and I will be cutting some heavy tubing pieces about 1" long to go over (but not add to their height) those little pads that are welded on now. I will just hold them on with a stainless clamp as I do not want to weld.
John

Re: Tire clearance issue

Reply #4 – March 16, 2013, 03:19:51 am

Conveyer belt material (like used for the rear mudflap) will be my choice. Farm/tractor stores may carry it.

Re: Tire clearance issue

Reply #5 – March 16, 2013, 06:08:10 am

Maybe a good selling point for the FSD shocks to help prevent the quick contact ? Would not do a thing for a twisting situation. Surely additional height stop would be the answer and lots cheaper than 8 FSD shocks.
Of course you could install smaller tires, with the trend of trying to use larger tires just adds to the issue.

FWIW
Dave M

Re: Tire clearance issue

Reply #6 – March 16, 2013, 12:31:15 pm

With the automatic level system our coach lowers to the point where the tires are occasionally resting against the bottom of the coach. This has left depressions in the skin at every tire location. There is a spacer installed to limit the amount the coach can lower. Has anyone increased the height of the spacer to prevent the tire to coach contact?

Re: Tire clearance issue

Reply #7 – March 16, 2013, 01:04:48 pm

Quote from: flite2010 – March 16, 2013, 12:31:15 pm

...................Has anyone increased the height of the spacer to prevent the tire to coach contact?..........................

Many have raised the existing tabs or buttons..
The question is how much to elevate the existing tabs. Too much and you may bottom out unnecessarily, going down the road. Not enough and uneven ground will still cause the tires to contact after leveling.
One of the options is slicing 3/8" thick (or whatever you desire) wafers out of round bar stock, equal in diameter to your existing buttons. Clean the mating surfaces well with alcohol, butter the mating surfaces with any good metal to metal glue (Gorilla glue works fine), hold them in place with temporary water hose clamps and lower the coach on them until the glue sets up.
Must hold them in place or they will creep and not remain centered on the existing buttons (more a visual issue than a functional issue).
Neal

Re: Tire clearance issue

Reply #8 – March 16, 2013, 02:51:19 pm

Exactly what I mentioned in another posting yesterday about adding 1' pipe spacers (see uh oh posting)
jOHN h

Re: Tire clearance issue

Reply #9 – March 16, 2013, 02:56:18 pm

Dave, IMHO using conveyor belting only decreases more the clearance between tyre and under floor. and if the tyre was to bottom out it would just rip that off and smell like a fire.
John H

Re: Tire clearance issue

Reply #10 – March 16, 2013, 03:28:15 pm

I think you might miss some of the clearance to level if you take it too far. Much hard to get level on a 40-42 than it was on my 34 36 version of the coach. i have not bottomed out running but I have set the coach down far enough to touch when leveling.

Re: Tire clearance issue

Reply #11 – March 16, 2013, 05:59:01 pm

Not sure how helpful this will be to hear, for I guess it depends upon what drives the concern for the coach resting on the tires. FOT told me it is not a problem to do that, it is designed to handle. I wonder if any readers know otherwise for I just took the FOT representative's guidance and so have not considered increasing that distance. And I suppose if one did increase that distance then it that it would not change the ride height or no one would consider doing this? Mike

Re: Tire clearance issue

Reply #12 – March 16, 2013, 06:04:00 pm

In six years I have found it to be a non-issue. In any FT with air bags, if you move the coach before the air system is fully pressurized, you're going to get scuffing, but just resting on the tires is no problem.

Re: Tire clearance issue

Reply #13 – March 16, 2013, 08:56:14 pm

Quote from: Michael & Jackie – March 16, 2013, 05:59:01 pm

..........................Not sure how helpful this will be to hear, for I guess it depends upon what drives the concern for the coach resting on the tires. FOT told me it is not a problem to do that, it is designed to handle. I wonder if any readers know otherwise for I just took the FOT representative's guidance and so have not considered increasing that distance..................................

Mike,
FOT told me the same thing. That the coach is designed to handle that contact. They also told me that my plywood floor delamination, near the area that the RF tire contacts when the coach is parked and leveled in my driveway, is not because of the "bowing" induced by the tire contact.

I accepted that for years, until good FT friends of ours parked a 2000, U320, 40', in the same spot in our driveway, for something in excess of a week and suddenly they had a floor delamination that they didn't have before parking there. Since then, I've found a few others with the same era coaches (1996 to 2000) that have flooring delamination. The common factors seem to be these model years and owners that routinely dump their air bags or level in locations that induce tire/floor contact. Of the ones that I am aware of, the delaminated plywood locations have all been in the general vicinity of tires that have been in contact with the floor for extended periods of time.

So you decide. It may be convenient to say that the coaches are designed to handle the contact, but why then does plywood flooring delaminate in that general vicinity?

I know of one owner that was able to inject some glue into the delamination (through a saw kerf) and then just lay in a pattern of wood screws. I know of another owner that had a patch of the floor replaced and the carpet relaid. It was an extensive job - several days - replacing just the (large) "patch" of the flooring. After seeing that, I just live with mine. When humidity is low, the delamination is not perceivable. When it is high, it can be very perceivable, even through the carpet.
If I'm right, it seems like others should have seen the problem. What have others found, in terms of delamination, when replacing carpets with tile or other flooring?

Neal

Re: Tire clearance issue

Reply #14 – March 16, 2013, 09:01:22 pm

Quote from: Neal Pillsbury – March 16, 2013, 08:56:14 pm

What have others found, in terms of delamination, when replacing carpets with tile or other flooring?

Neal

Sounds like an invitation for Ernie to chime in.

Re: Tire clearance issue

Reply #15 – March 16, 2013, 09:09:22 pm

Quote from: amos.harrison – March 16, 2013, 06:04:00 pm

In six years I have found it to be a non-issue. In any FT with air bags, if you move the coach before the air system is fully pressurized, you're going to get scuffing, but just resting on the tires is no problem.

Brett,
We all know that not everyone has been as fortunate as you.
Dump or Not?
Neal

Re: Tire clearance issue

Reply #16 – March 16, 2013, 09:22:18 pm

Another reason to carry a spare bag with you. Depending on your location, you may not be able to move the vehicle without causing damage where the tire makes contact if the bag has a severe leak. Plugging the line didn't do the trick on ours.

Imagine trying to install chains or better yet, imaging what the chains could do to the wheel well.

Pierce

Re: Tire clearance issue

Reply #17 – March 16, 2013, 09:23:18 pm

Nono! I meant using layers on top of the existing bump stop to add clearance (keep the tire further from the wheel well!)

Re: Tire clearance issue

Reply #18 – March 17, 2013, 02:23:47 am

We carry an emergency length of 4" x4" wood that we could put between side-to-side frame members to allow us to drive coach with ride height problem and not let tire touch floor.

Re: Tire clearance issue

Reply #19 – March 17, 2013, 11:53:22 am

Maybe I am wrong but it looks like we have a mix of issues in this posting.
1--- I do not dump air but have had tyres resting on underbody floor which I do not like, that is why I am going to put those washers on as I mention. I personally do not trust the floors and when you hit a large bump in road or?
2-- If you have a bag failure while travelling then Barry's idea makes sense to me as a "get to a shop fix" and having a spare as Pierce mentions also makes sense, but you can only prepare for so many problems to happen without towing a truck full of parts.
I have a little plastic card that is my "spare parts" collection, but yes, things can happen in the middle of nowhere or do not carry the right tools to fix anyway. (or the ability to )
John H

Re: Tire clearance issue

Reply #20 – March 17, 2013, 12:05:37 pm

Sorry, read it wrong. Maybe instead of putting it on top of stop just put a few layers next to it so they are higher than present stop. I just think if you put them on top of it ,ultimately they may get cut thru by weight of coach pressing on it. Sort of like a "punch"

John H

Re: Tire clearance issue

Reply #21 – March 17, 2013, 03:08:17 pm

Anything one can do to prevent being towed is worthwhile as towing can cause additional problems.

Re: Tire clearance issue

Reply #22 – March 17, 2013, 06:35:41 pm

A good trick we always used to make sure the right rear tire was larger in circumference than the left rear was to chalk a tire and the ground (at operating pressure) at the spot where it met the ground, roll or drive until the tire chalk mark was at the ground again, mark the ground and measure between the lines. While not a race car, the same method applies if you do that against another brand/tire on the coach. You can compare circumference exactly. Have to have both tires at the same air pressure. Another coach close by can be also compared.

Take the circumference and divide by pi or multiply by .7854 to get the exact diameter.

Pierce

Re: Tire clearance issue

Reply #23 – March 17, 2013, 10:36:50 pm

Quote from: Neal Pillsbury – March 17, 2013, 09:34:58 pm

It can be easily prevented through inexpensive frame-to-suspension-travel-stop button modifications or by just not dumping or auto-leveling suspensions into high pressure tire-to-floor-contact situations.
Neal

Guess I'd want to exhaust all other alternatives before I raised the bump stops with a non resilient material, seems like you could jump from the pan into the fire doing this. It also, of course, reduces your leveling range but a buckled floor is nothing to sneeze at either as components other than the floor (wall bond, paneling, cabinets) could also be affected. Seems like the key is care in leveling to avoid tire contact. Since we tend to get into some pretty primitive sites that often exceed the leveling capacity of our 36, to say nothing of a 40, I've been idly considering some air lift bags for these situations. I am sure I don't want to lug plywood around!

Chuck

Re: Tire clearance issue

Reply #24 – March 18, 2013, 12:18:29 am

For Chuck, Neal and Dave....and John H. too.

I think I understand both views of discussion....to change it or leave it as designed, and a distinction between some as being apples and oranges, others not so. I generally like leaving things as the factory said but see your points. Then Chuck introduced another thought about primitive site leveling and Neal talked about designs differing from some years. With regard to those.....

1. I have a 2001 and there is wheel scuff on the wheel well. It does not seem to have damaged anything but it is slightly indented. I wonder the if that is correct, I am safer in a 2001 for this than say a 1999 or it just happens mine looks a bit better. The 1999 - 2001 coahces seem so similar to me.

2. When parked on a sloped site, the wheel well rested on the passenger front. It became as Chuck or another of you define, the support point that determined all else. That worried me. So I called James Tirana at FOT and he told me not to worry, it was designed for this. (But this discussion has me wondering again.)

3. I had determined that this year rather than lug around a 5.5 inch platform for the front wheel that I would decrease the passenger side platform to 3 inches so the wheel well does not rest on the tire. Just seems better to me in spite of what I heard from FOT. This discussion raises the question I had, perhaps I should not have let it rest on the tire while parked.

4. I have met one fellow in a park who rests his coach on all the tires. I think better than only one touching.

I thought that I recalled in our operations manual from FOT that we could in fact move the coach, slowly, in the dumped air position? I assume that is rubbing on some or all of the tires and wheel wells. I guess I need to see if I can find that reference.

Thanks for an informative discussion. Mike

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