[Archived]

The inner wheel is an 8.25 X 22.5. It is the original steel wheel. The exterior

wheel is a 90 X 22.5 aluminum. There was no protector between the two. The

new 315/80R22.5 Michelins call for a 90 width rim. Since I am replacing all

the lug nuts, do I go with steel again or aluminum? Any advise would be

appreciated.

[Archived]

John

It was common practice for years to run steel on the inside of the dual, I don’t agree with that but it seems to be ok.

If you go aluminum you need longer studs, the wheel is thicker and you need to make sure you have fender clearance.

I question how anybody could check air pressure on the inside tire the way your set up with that black cap on the stem. That is wrong. You need the double seal cap so you don’t have to remove a cap from the inside tire to check pressure.

To me it looks like a zipper tear and there’s a black abrasion in the middle of the tear. Could be due to underinflation but that’s a guess.

Later

bv

On an edit here thinking about clearance. You can run 8 1/4 rim on a 315 tire you just can’t use the tire to it’s full weight rating at 130 psi but your not that heavy back there anyway, I don’t think I would change anything due to fender clearance.

You need to measure if you change anything.

[Gerald]

When Prevost made the switch from 120 ti 315 tires they went with a steel inner wheel to keep the width of the drive axle tires between the coach fenders. If you replace the steel wheel with aluminum ones I believe the additional width will cause the outer drive wheel to rub the diver axle plastic fender.

Recently Michelin appeared to change their posture regarding the acceptability of using 8.25 wheels with 315 tires and issues a new chart regarding 315 tires mounted on 8.25 wheels. They do not encourage the use of 8.25 wheels, but apparently will allow them as long as the loaded weights have the corrected pressures.

Note that for a given weight the pressures for 315 tires varies depending on wheel width.

The use of a Pressure Pro sensor on the inner dual regardless of wheel width is OK because it eliminate the valve stem extension, and using the tool Tom designed to access and remove the sensor and a straight foot tire chuck that inner wheel and tire is set up perfectly.

If I am correct all Prevost coaches between around 1995 and 2000 ran steel inner drive axle wheels.

[Archived]

You don’t need a valve stem extension running a Haltec double seal cap.

Later

bv

[Archived]

Could it be possible that you maybe ran over something that got caught between the tires? That mark on the failed tire looks like some that I have seen in the past on trucks. What does the outer tire look like in the spot facing the failed tire? The mark on the tire looks kind of like a bruise, hence the question.

That could explain the failure easily if it happened.

[Archived]

Please check out what I am fixing to post with Prevost or good tire guy.

If you replace the inner dual with an aluminum wheel you will need to change the studs to ones for aluminum wheels.

The studs from alum to steel are different than ones from alum to alum.

I had this problem on my 99 CC when I replaced the inners with alum.

[Don]

The double seal caps are absolutely the best thing we can do for our tires as Bernie says, but anyone that uses a valve stem pressure sensor is screwed.

All valve stem pressure sensors open the Schrader valve as they are installed. It is the only way an external sensor can read tire pressure. But if a coach has the internal sensor as the newer Prevost coaches do then the valve stem caps should be the fill through caps which not only eliminate the need to remove them when adjusting tire pressures, but they provide a second seal to supplement the Schrader valve.

[Archived]

I bought a 2000 CC and the owner put 9” aluminum’s on the inside, I took them off because of fender rubbing, especially when lowering the suspension.

With your drives weight John you should have no issues with the 8.25.

[John]

Thanks to all that have replied.

I am aware that I would need to change the inner cap nuts to the ones with the shoulder to fit into the aluminum wheel.

That black cap on the stem is my pressure pro sensor. I do have one of Tom’s patented removal tools. My pressure pro alerted me to the bad tire after the explosion with a Tire has zero pressure alert. Prior to that the drives all ran at 110. There is no line around the casing indicating the tire had been running low and over heating.

How much clearance do I need to run two aluminum wheels and where do I measure?

There are no marks on the inside wall of the outside tire, so I would not be inclined to think something was stuck in between. I think it is just a result of the explosion. There is a lot of force when a tire unzips like that. I experienced it once up close and personal when I was working at the tire company. I ended up 30 feet across the parking lot.

[Archived]

John

michelin has a separate sub chart for tire pressure of 315’s on 8.25 wheels. We put 315’s on the Beaver Bus 8X8.25 wheels all around. Original tires were 12R

On our current sister coach to yours 0593 has Michelin XDN Grip 2 on the drive. Theyre are a much beefier tire than the XZA2 and we had clearance issue with drive axle lower shock studs. W wider inner dual may mimic our beefier tire issue. Just watch it.

[Sid]

I may be thinking of another post, but I recall you saying that Tire dealer or Michelin Rep. was going to inspect the damaged tire?

Would like to hear their opinion.

[Jim/Chris]

I have not dismounted the tires yet. I do have a claim started with Michelin

and I will post the results.

If I stick with steel rims on the inside, can I use a 90 wide instead of 8.25?

Tom, cover your ears for a minute. Does anyone have any info on the Beru TPMS

that Prevost is using on new coaches? Are there any other internal systems

worth considering? Sorry Tom, but remember Bernie brought it up first.

[John]

I have spoken with Prevost a number of times about “updating” my drive wheels and tires. Unanimously, Prevost has said that I “cannot” change the 8.5’s to 9’s and I “cannot” install the somewhat larger metric tires on the 8.5’s on the drive axle. They are “cool” with larger tires on the steer and tag smaller wheels and I have done this successfully in the past. I now, once again, I have 12R/22.5’s all around. It’s really not worth the effort to change as there is no noticeable difference in the various setups. If you have a coach that needs 12R/22.5’s, install 12R/22.5’s and go back to bed! There is exactly ZERO percent chance that you will find any benefit to a tire of a different size.

[Sid]

1. Hi folks I need a front bumper latch . Prevost delivered thiscoach

with that front storage area for a spare tire. CC changed it to use a latch

that could be released from inside or manually from the doors by the driver side. Mine has fallen and will not catch. Anybody know where I can get one?

[Archived]

John,

You said your inner wheel is 8.25 and your outer is 9. I would think that would make your tire sidewalls flex differently. If you mentioned that in your claim they will most likely pin that on the cause. If you measure the space between the tire and rubber fender on the other side and it is 1″ or more then you should be ok to put alu. on the inside without rubbing on the fender. I would not recommend using 9″ on the inside. As far as the studs go, you do NOT have to change them to run alu. inners. You DO have to make sure you use the correct inner cap nuts (e-5978) or catastrophic failure is in your future.