19.5 Wheel upgrade HELP NEEDED please

[Hotrod460]

I am currently running stock wheels w/ 8R 19.5 tires= 8.2” wide x 34”
The tires are too skinny at the duals- I’d like to go w/ aggressive tread. 245’s are all that’s really available (9.5”w x 33.5” tall) so they are shorter. I want to bring the rear end up more- not down. Also the 245’s may rub.
Can I get different wheels and then taller tires without changing the hub?
Any help would be great. And if anyone is selling tires/wheels please let me know.
I put 245’s on the front. They are much wider than the old pizza cutters.
I’d be fine with changing all the wheels if needed.

Thank you!
Happy Camping

[yeloduster]

Please tell us the chassis brand, year and model. This may get more and better responses. You might add chassis information to a signature line for your posts.

I used 225 70/R19.5 tires on the front of my P32 Chevrolet chassis. The 245 70/R19.5 tires are too wide for the wheels on that chassis and weigh considerably more than the 225 70/R19.5 tires. I didn't want additional un-sprung weight that would have contributed to handling/ride problems.

I stayed with the 8R19.5 tires on the rear of my motorhome.

Just curious, do you want wider tires on the back because they look better or for an improvement in performance.

[Soppy]

I changed from the 8R 19.5 to 225 70 19.5 on my p30 chassis. That is the widest tire that you can fit on the stock rim. It is also the widest for the proper spacing when used as a duel tire. Going to 245's , you will have to replace the rims.

[Hotrod460]

The whole point of my post is to upgrade wheels to different size to allow for taller tires.
Looking for info on what wheels interchange with Oshkosh chassis.
Or would I have to change hubs?
Thanks

[camper8251]

Call a tire shop........ They could answer the question better than anyone here.

[johnhicks]

If you have six lugs, they're Budd lug-centered rims. Accuride lists them but only six-inch size, which is what you have

[yeloduster]

You still haven't told us your chassis. But based on your desire for a wider tire that is also taller than 34" I think you will have to go to a 22.5" wheel/tire combo such as this wheel: 22.5 American Force Beast and a 9R22.5 tire such as 9R22.5 Toyo Tire

At 9" in width and approximately 38.5 in tall it meets your requirements. I have no idea if it would fit in the wheel well. In addition it would effectively change the gear ratio requiring a speedometer change and the taller tire would reduce the amount of torque at the tire/ground contact point and reduce the pulling power.

It would also cost a lot of money.

[tderonne]

OP already said:

Originally Posted by Hotrod460

... Oshkosh chassis.

[Hotrod460]

Thanks guys. Mainly I am just trying to get the engine and transmission pans off the ground more. I take this thing deep into the forest.
I’m good a sourcing used parts. I appreciate the 19.5 x 7.5 info.
Or if nothing else perhaps I’ll get lucky snd find aggressive
8R 19.5 tires. I thought going taller would make it slower off the line but better MPG’s.
Would hate to lose torque. Couldn’t see it being that much though...
Thank you!
Jeff

[Hotrod460]

Check these out!
https://simpletire.com/brands/goodye...&mpn=139065028

[yeloduster]

Originally Posted by Hotrod460

Check these out!
https://simpletire.com/brands/goodye...&mpn=139065028

Hi Hotrod,

I had a 1988 Bounder on a Chevy P32 chassis. The factory tires on it were 8R19.5. I changed to the 225/70R19.5 tires on the front but kept the 8R19.5 highway tires on the rear. I too go off road. I never worried about bashing the engine or transmission pans. The motorhome set down over the frame such that the motorhome body would get whacked before the drivetrain stuff. I only bashed the body once!

Have you had it into the locations you wish to take it? If so how was your traction. I found that I had excellent traction. My favorite spot is 1O miles of dirt (not gravel) road off the pavement. On two occasions while I was towing my Jeep there was enough rain that the top 3" of the road was mud. This road has several grades of about 10% for short distances and was curvy and rough enough the 15 MPH was about the top speed I could go. The driver tires slipped a little a few times but I never had problems.

I also drove Monarch pass in a early 6" snow storm before the snow plows got there. I once drove towing the Jeep from Mammoth Hot Springs Yellowstone National Park to Sheridan, WY via I90 in an almost blizzard. There were cars and SUV's all over the ditches and I never spun a wheel.

What I'm trying to say is you may have plenty of traction with highway tires. Motorhomes put a large percentage of their weight on the drive axle. Maybe that is enough.

Whatever you decide good luck. I looked around and other sources for the traction tire in 8R19.5. Here are a couple places at a far less price: SpeedyTire and Amazon

Hopefully they actually have tires...not just a good price for tires that are out of stock!

[Hotrod460]

I ended up ordering 4 Goodyear’s for $800 delivered from simpletire ! Should help huge when out in sketchy areas.
Peace ��☮️
Goodyear G633 RSD, 8.00/R19.5