W20 chassis w/ 19.5 to 22.5 wheels question

[Richard 34A]

I have a 2005 W20 chassis that has 19.5 wheels but would like to upgrade them to 22.5. Is this possible, and does it affect the speedometer?

Thanks for any information...

[Richard 34A]

I have a 2005 W20 chassis that has 19.5 wheels but would like to upgrade them to 22.5. Is this possible, and does it affect the speedometer?

Thanks for any information...

[rvten]

I have seen W-20's with the 22.5 tires. Yes pretty sure it will change the speedometer reading. The bigger tires will also increase your over all height. So you will want to mreasure it for those low over hanging places.

[M&EM]

Also will affect the reach of your leveling jacks.

[edgray]

Yes it will effect the speed and the odometer. More problematic will be trying to determine IF the coach's wheel wells and other coach supporting framework will allow the larger tires. You'll wnat to know that before spending all the money on new tires and rims. ED

[Bob (WA0MQE)]

Richard... The 22.5 inch wheel and tire will be substantially larger and the ratio of your differential may or may not work well with the size difference.

[FrontRangeRVer]

Why change them?

I would leave them at the current size as Winnebago and your chassis maker engineered your unit for the 19.5" size.

[Richard 34A]

Thanks for all of the replies; I like the looks of the 22.5's but didn't realize all of the possible problems.

I have a sedan that I went from 16" to 18" and it didn't affect the vehicle, (probably due to easy availability of lower-profile tires than a MH) so I guess this upgrade is off my list.

[Fakrwee]

You will also feel a loss of power. Gears are matched to wheel size for optimum performance. If you change that ratio you will notice a loss of power, especially going uphill. The only advantage would be on perfectly flat road where you're RPM's would be less than with the 19.5. Overall I think you would lose performance. This beside the other problems mentioned above.

[DriVer]

Don't forget that the gears in the differential are also different. 19.5 inch wheels on a W20 use a 5.13 ratio. The W22's 22.5" wheels use a 5.86 rear end.

[max49]

I'd rather have the 22.5's too but the only pactical way to do it would be to sell this one and buy another MH with 22.5's

[DriVer]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by max49:
I'd rather have the 22.5's too but the only pactical way to do it would be to sell this one and buy another MH with 22.5's </div></BLOCKQUOTE>

[alvinc]

No one has mentioned that the 22.5" rims and wheels are larger, and plain will not fit without rubbing.

There are two possibilities though, both have the same issue with the rear axle ratio:

1) Your "house" was manufactured with a 22.5" wheel and then mounted on a 19.5" wheel chassis.

2) Put a lift on your motor home to provide clearance for the larger tires. This could be a block lift (dangerous), you could have new springs made, or the current springs re-arched (assuming there is enough shackle play).

How about it Mike? Is Brazel's going to offer a lift kit for the Workhorse chassis?

NOTE: putting large tires on vehicles is one way of getting better gas mileage at the expense of acceleration and performance. My dad did it to several of his cars. It effectively moved the RPM's lower at the same speeds. Would this be a good idea on a W20? I don't know.

[Richard 34A]

Well, I now see where my confusion came in; I thought the 2007 Sightseer on a Workhorse chassis now came with 22.5" tires and wheels, so I thought it was a simple upgrade. Going to the Workhorse web site, it lists the W20 still with 19.5"s and the W22 with 22.5"s...