Tire Vibration?

If the coach is owned by PPL, then ask them to fix the problem and then deal on the coach. Find someone there who knows something about the problem and work with them to get the shaking problem solved. You shouldn't have to resolve the issue unless you are getting SUCH A DEAL that you want to take a flier on fixing it yourself. All of the suggestions here are great and you can have them in your arsenal when you next talk with PPL, but they should MAKE IT RIGHT before you buy.

That's how I see it. Good luck

Also, if the tire is balanced with sand or beads, it could have settled in a spot. This causes a big bounce in the tire at some speeds. When it happens to me, I stop and roll forward and back to loosen things up. Of course, if the salesman is that clueless, there's no way to know if this is the case.

BigLar368 wrote:
Thanks for all the advice. We are going back in a week or so and drive it again. I feel the tire probably just has a flat spot. It has been on their lot since August. The salesman said no one has even tried to make an offer on it. With diesel being as inexpensive as it is now seems like everyone is going for the longer MH's.

BigLar368,
Well Sir, first off, why would only ONE tire have a flat spot? I mean if all the tires are dated close to the same, as in they've all been on the coach for the same amount of time, and the coach has been sitting for a while, then if the coach tire(s) were to develop a flat spot on one, it would do it to all of them.

You could do a very simple test here without to much technology involved. I'd put that coach on some flat ground and, lower the Jacks 'till they hit the ground. Then, raise the front end, 'till the front tires are just BARELY off the ground. All you need is daylight under the one in question.

OF course the parking brake is set already (you can't lower the jacks if it isn't)so, the coach is not going anywhere. Now, what's needed next is an object, a coffee can, block of wood, anything that will sit sure-footed on the ground that's not very high. All you have to do is put that object very, very close the tire tread. Then, spin the tire slowly.

What you're looking for with this very simple test is this. If the tire is "Out of Round", as it spins, it will move considerably closer to the object you've placed in front of it. You'll see the clearance decrease and increase, between the tread and the object if the that particular tire is out of round. This test, putting the jacks down and raising the coach to the point the tire's off the ground, will take about 3-4 minutes.

Then you'll know for sure if you're dealing with an out-of-round tire. You of course can do the test to the left front too, while the coach is up off the ground a bit.

Now, that test primarily reveals out-of-roundness. It will not show "out of balance" issues. Now, I've not heard of it on Motor home tires like I have on trailer and regular vehicle tires but, you might possibly find a tread separating too which, would show up a bulge in the tread face at one portion of the tire. Again, never really heard of it on a motor home tire.

But, if you like the coach, and all else is well, then a balance problem or vibration shouldn't cause you to back off of the deal. Nothing is that hard fix, especially a vibration. A good tire shop or truck front end shop should have that problem diagnosed in minutes.

And, as far as "Salespeople" actually "KNOWING" about what they're selling, well, you've more than likely seen that before. In all reality, not very many sales people are truly knowledgeable about their products. Many will "talk" like they know a lot but, I've put many of them back in their chairs. There are a few, VERY FEW, that really know their stuff and can accurately answer questions, describe what a coach is and how it works and things like that, but not very many. Good luck on your endeavor.
Scott

As far as where I could feel the vibration it was everywhere but more noticeable coming from the right side. The passenger mirror was shaking so bad you could barely see out of it. It got worse as the speed increased.

Thanks for all the advice. We are going back in a week or so and drive it again. I feel the tire probably just has a flat spot. It has been on their lot since August. The salesman said no one has even tried to make an offer on it. With diesel being as inexpensive as it is now seems like everyone is going for the longer MH's.

Have it driven to a repair shop of the maker of the chassis/drivetrain and have them inspect the front end components for problems. Eliminate the front end components will leave the tires as the suspected problem.

Could you feel the vibration in the steering wheel? Or was it felt more in the seat? Alignment or balance problems you can feel in the steering wheel an out of round tire like a flat spot from sitting too long will be felt in the seat. A quick check would be to jack the front tires off the ground about 1/4 in and spin the tire slowly and look at the gap between the pavement and the tire and see if you have more that 1/8 in out of round condition.

I would look at the tires and see if you see any wheel weights. If there are none, the previous owner may have used the balancing POWDER instead of the balancing beads. The powder tends to clump, especially if there is any moisture present. This clumping can cause the vibration you are experiencing. The fix is remove the powder from the tires and re-balance them.
If the tires are out of round, they can be shaved to make them round.
Other than those things, the next step is to have the entire front suspension checked for worn shocks or any loose or worn components.

If you really like the coach otherwise, make an offer: "Contingent on fixing front end vibration problem to buyer's satisfaction".

Could be a number of causes, but correct order is to check tires for run out, flat spots or defects. Only if OK, balance them. Balancing on the rig is best, as all rotating masses are then in balance.

It could be flat spots on tires from the coach sitting for a long time on the lot.

Not saying they don't need balancing, but driving it for 20 miles or so should heat up the tires and round them out.

Did you look at the tread? Any unusual wear patterns or cupping?