4104 spare tire modern size

[Bountyflyer]

When I bought bus #2 (GMC 4104) I ended up with 2 extra wheels. (Modern tires mounted on old steel rims) When I was trying to put one of them in the spare tire holder space behind the front bumper, I couldn't close the bumper.

The very vintage looking tire what I pulled out from the space was a 12.5 - 22.5 tire. Without the rim and off course inflation it fit wonderfully to the factory spare tire space. I can't seem to find this particular size anywhere.

What is a modern tire what would actually fit in the spare compartment?

Do you put your spare where it belongs to? Or just put it in the baggage bay?

I've seen firestone is selling an "off road/hi way" tire. Since we go camping a lot what sometimes involves unimproved dirt roads would you recommend a tire like that?

Would this fit in the spare tire compartment?

https://commercial.firestone.com/content/dam/bcs-sites/bridgestone-ex/products/firestone/TBR/T819/Firestone_T819-ProductSheet_06_2015.pdf

What is your favorite bus tire?

And the final, million dollar question:
HAVE YOU EVER EXPERIENCED A FRONT TIRE BLOW OUT?

How bad is it? I had tires blown on my airplane, car, bicycle, and wheel barrel, so I often wonder about how will it feel when I'll loose a front tire in my bus... Please feel free to scare me!

[Nova Eona]

You might be able to gain a smidge of extra clearance if you remove the curved metal 'tire guide' on the back of the bumper (if still present) - won't really need it if the tire ends up sitting flush.  My 4104 has 11r24.5s on it, I'm just running without a spare and considering tucking a generator into the vacant spare tire compartment.

When I was shopping for new rubber recently, I looked at the T819s as well, but the 65 mph rating scared me off - I realize most 4104s need a steep downward grade to hit 65 with any regularity, but I didn't want to be running that close to the limit even so, and I suspect my 24.5s will get me there more often than some others.  Wound up ordering a quartet of Dayton D620Ds for the drives and Bridgestone R268s for the steers.

Hardly driven the thing since I got it and certainly haven't had a steer blowout myself, but I've read and watched some training videos on it out of a similar fear.  My understanding is that so long as you can remember to counter-intuitively *accelerate* into it initially rather than slamming the brakes, it's manageable - better to ruin the rim slowing down at your own pace than to jackknife the bus by stomping the brake.  The bright side to all of the above is that modern tires are far less prone to catastrophic blowouts than they used to be, and a good TPMS will usually let you know something's wrong before you're birthing gators on the freeway.  I'm sure others will be chiming in with real-world experience shortly!

[chessie4905]

They are a slightly larger tire that is overkill on a 4104. My parts coach, a 4905 has that size on one front and a 12.75 r22.5. on the rear.They were used when the standard tire, 12.00 r22.5 didn't  have enough margin to suit the operators. Also was used on some 4905 to gain a couple more mph speed, as their standard axle ratio was 4.27.

[dtcerrato]

We're running 11 - 22.5s for 40 years. Always a new inflated spare behind the bumper. 4:11 diff. 65 mph top end. Suits us well. We do a lot of mountain driving.

[freds]

Hardly driven the thing since I got it and certainly haven't had a steer blowout myself, but I've read and watched some training videos on it out of a similar fear.  My understanding is that so long as you can remember to counter-intuitively *accelerate* into it initially rather than slamming the brakes, it's manageable - better to ruin the rim slowing down at your own pace than to jackknife the bus by stomping the brake.  The bright side to all of the above is that modern tires are far less prone to catastrophic blowouts than they used to be, and a good TPMS will usually let you know something's wrong before you're birthing gators on the freeway.  I'm sure others will be chiming in with real-world experience shortly!

Links or search terms for the videos?

[buswarrior]

Michelin has the blow out videos

The test drivers are pretty nonchalant about it.

It's only a problem because the bang scares you, and then you react wrong.

Happy coaching!
Buswarrior

[Nova Eona]

They are a slightly larger tire that is overkill on a 4104. My parts coach, a 4905 has that size on one front and a 12.75 r22.5. on the rear.They were used when the standard tire, 12.00 r22.5 didn't  have enough margin to suit the operators. Also was used on some 4905 to gain a couple more mph speed, as their standard axle ratio was 4.27.

I was on the fence for a long time about keeping them at 11r24.5 or going to a smaller size, but in the end it sounds like, as is often the case, people tend to prefer whatever they currently have on their bus; I have yet to see anyone reporting that they were unhappy enough with their 11r24.5s to downsize their wheels, but have seen several that were happy with the change.  I figure the small increase in top speed on the flat will probably be an acceptable exchange for slower times uphill, and that the difference in % grade starting ability for 22.5 is probably not that much greater than 24.5 (particularly since the standard guide for starting a 4104 on a grade is, if at all possible, to avoid doing so).

Links or search terms for the videos?

There are a number out there, but I remember the arrow diagrams used in this one sticking with me (written for S&S RVs, but same principles apply)
https://www.youtube.com/watch?v=lkwOE1yKY5c