MaxPack upgrade

[JoeDS]

A new option on the Windsport and Hurricane is the MaxPack upgrade package which gives you 22" wheels, aluminum rims, and more storage.


Does anyone know the load carrying specs on the 22" inch tires vs the 19.5" tires? I'm sure the chassis specs are the same but I would suspect the 22" tires would allow more cargo weight before you max out?


If nothing else I would think the 22" tires would ride better.


Would the increased height require one more step to get into the coach?


A lot of questions but it is such a new option I'm very curious about it and have no way to get any practical info about it.

[Beau388]

Originally Posted by JoeDS

A new option on the Windsport and Hurricane is the MaxPack upgrade package which gives you 22" wheels, aluminum rims, and more storage.


Does anyone know the load carrying specs on the 22" inch tires vs the 19.5" tires? I'm sure the chassis specs are the same but I would suspect the 22" tires would allow more cargo weight before you max out?


If nothing else I would think the 22" tires would ride better.


Would the increased height require one more step to get into the coach?


A lot of questions but it is such a new option I'm very curious about it and have no way to get any practical info about it.

Increasing the diameter of tires does not change the max weight capability of the chassis. If a 22,000 lb chassis has 19.5" tires or 22.5" tires, it is still a 22,000 lb chassis. Generally the taller the tire (higher aspect ratio) the better the ride, but worse the handling because of tire squirm. The larger diameter tire (not the rim size) will usually give more tread life. Remember it is the air in the tire carcass that holds the coach up. You can achieve the correct amount air by high pressure in a smaller volume tire or by a low pressure in a large volume tire.

[JoeDS]

Yes, I stated that the chassis was the same. But the 22" tires "usually" do have more capacity depending on which size tire is used.


The following is probably far more information than anyone wants! But I had fun learning about it.


As best as I can determine from digging around on the Ford website (believe me there is room for error. Its not exactly clearcut) If any of you have a windsport/hurricane with 22.5 inch tires please post what your factory sticker says.


The Ford F53 chassis has 7 versions that range from GVWR 16,000# to 26,0000# and GCWR from 22,000 to 30,000#


windsport/hurricane models :
31,32,33 series use the 228" wheel base with GVWR 22,000# and GCWR of 26,000 #
34,35 use the 242" wheel base with GVWR 22,000 and GCWR of 26,000 #


If 19.5" tires are used they are 245/70 R19.5G Total load at 110 PSI is 26,220# max load with 6.75 inch rim (inc de-rating for dually)


As best as I could determine from some 2018 data, if you have 22.5 inch tires they are 235/80 R22.5"G with 7 or 7.5 inch rim and at 110 PSI are rated at 26,990 # load. Only an additional 650 #. However with the 22.5 inch tires with the wider 7.5 " rims you do have the option of moving up to a much hinger load rating which is obviously what the larger heaver rigs have to do.


Whew!!!!

[JoeDS]

The following is kinda crazy silly, but I've done worse before.


I added up how much extra you could add to the dry weight of the Windsport 35M with 4 holding tanks


80 Gal gas 480#. 208 Gal fresh water and full waste tanks 1,734#. 88# propane. Family of 6 900#. 500 # for towing that Jeep on a dolly. That adds up to 3702# wet.


Now add clothes, food, chairs, BBQ grill, kitchen sink and on and on .....


As everyone always advises WEIGHT your rig. Weight can sneak up on you!

[The_Breeze]

When you start jumping into the 22" ranges you start approaching tractor trailer tire sizes capable of more weight because they have more plies and the result is more psi to support that. Not that they can't build that into smaller diameters. They choose not to.

If the rim size is the same, then the aspect ratio conviction can be true and the sidewall flexes more. If you're comparing width, I don't think that necessarily affects load capacity without taking other factors into count such as air pressure and number of plies. A smaller width could introduce more sidewall flex because it bears more force on a smaller tread width. We can go into laboring detail on those physics for an eon and it's just not in me to do that anymore.

I think moving to 22 is a good, given the number of plies and their make up supports more load capacity (e.g. steel v. polyester v. fiberglass, etc)

Here's a lot on minutia on it for your entertainment
https://patents.google.com/patent/US20080149250

[JoeDS]

Originally Posted by The_Breeze

When you start jumping into the 22" ranges you start approaching tractor trailer tire sizes capable of more weight because they have more plies and the result is more psi to support that. Not that they can't build that into smaller diameters. They choose not to.

If the rim size is the same, then the aspect ratio conviction can be true and the sidewall flexes more. If you're comparing width, I don't think that necessarily affects load capacity without taking other factors into count such as air pressure and number of plies. A smaller width could introduce more sidewall flex because it bears more force on a smaller tread width. We can go into laboring detail on those physics for an eon and it's just not in me to do that anymore.

I think moving to 22 is a good, given the number of plies and their make up supports more load capacity (e.g. steel v. polyester v. fiberglass, etc)

Here's a lot on minutia on it for your entertainment
https://patents.google.com/patent/US20080149250

What I noticed on digging around and it was kinda buried in all of the info is the 19.5 inch tires only had a 6.75 inch rim which greatly restricts any larger tire. The 22.5 inch tires with 7.5 inch rims allow you to go up to f and j load range wider and tires if you wanted to. The 242" and 252" chassis with the 24,000# and 26,000# rating only come with the 22.5" tires.


I also found out I missed a chassis in there . The Miramar and the Challenger models each have 2 models that use a 262" chassis on the F53 frame with a 30,000# GCWR. Those appear to be the largest motorhomes Thor makes that still use the Ford chassis and engine.


No wonder my Vegas 24.1 has so much pickup. My little rig has the same engine and is 15 feet shorter than those big rigs! I have to feather the gas peddle at every stoplight to keep it from leaping off the line!

[Beau388]

A lot of different manufactures manufacturer 245/70-195 tires. My coach has Sumitomo ST718 tires (133/131M load rating). That is 9,080 lbs max on the 7,000 lb capable front axle and 17,200 lb max on the 12,000 capable rear axle. That is 26,280 lbs at 110 psi for 6 tires which should be enough for a 22,000 lb chassis. These tires run at 5 to 8 lbs less pressure build up as compared with the old Goodyears when starting at the same pressure (82 psi recommended).