"Thinking Outside the Box" Wheel/Tire swap on Vegas

[gmtech16450yz]

Those aren't dumb questions guys, quite the opposite. Jamie and L&W, you pretty much nailed it on your assumptions.

https://www.michelinman.com/tire/michelin/xps-rib

The XPS Rib tire is a steel cased tire. It has a lot stiffer sidewall than light truck tires. If you've ever overloaded your pickup truck and had it wander and float around like it's driving in jello, that's what a soft sidewall does under heavy loads. That's also exactly what these RV's do when they're running light truck or SUV tires. If you drive down the road and swerve back and forth, you can feel the sidewalls flexing back and forth. You can really feel if if you move the steering wheel back and forth just a couple inches so that the RV is still going straight but will squirm side to side just on sidewall flex.

With tires like the XPS Rib, that feeling is GONE. There isn't any "squirming" or "floaty" feel to the rig. It's a big difference. The downside is that stronger sidewall gives a firmer ride. That's why I went taller, like you guys thought, to give it back some amount of sidewall flex. And yes, the wheel speeds went from about 710 revs per mile to about 650. That slows that rotating mass down, which helps keep everything running a little cooler.

gnach- If you're talking about the wheel well flare, if you look at the before and after pics you can see there's a gap at the bottom after. Thor ran the flares all the way to the bottom of the body, which actually looks weird. Fender flares aren't normally that low. I simply raised them up so they have gaps between the bottom of the flares and the body. It actually looks better to me that way. I'm really happy with the looks of the whole front end now. It doesn't look weird or out of place, it actually looks "normal" now. That's one of the comments we got on this Vegas constantly since we bought it. So many people have said "Why are the tires so small?". lol.

Thanks for the comments guys! I really think Thor should have done this themselves to these E350 and E450 chassis. It used to be common for dual wheeled Dodge B300's under Class C coaches to have standard single's in front. It made it so you couldn't rotate the wheels front to back, but if you buy good tires and replace them when you should, you really shouldn't have to deal with blowouts or flats unless it's a road hazard situation.

First pic is stock Hankook 225/75/16 tires that came on our '18 27.7- second pic is 235/85/16 XPS Rib- notice the tire weights and max loads...

[Chance]

Insanely dangerous


Installing SRW wheels on a DRW front hub is going to get you killed, or worse yet, get some innocent person killed.

I know your insults will follow, and I had promised myself to ignore you completely, but this “thinking outside the box” modification to widen the front track is so wrong, on so many levels, that I must warn others not to even think about trying it.

It is by far the most dangerous idea I have seen anyone implement on this forum.




P.S. — Nice look — will give credit where deserved.

[16ACE27]

Originally Posted by Chance

Insanely dangerous


Installing SRW wheels on a DRW front hub is going to get you killed, or worse yet, get some innocent person killed.

It is by far the most dangerous idea I have seen anyone implement on this forum.

And the reason is ............................?

Inquiring minds want to know.

https://www.youtube.com/watch?v=73tGe3JE5IU

[Muggs]

Looking at the swap on front, I do not see an issue. The point of max hub load is still close to original design.

If wheel offset was too far out adding leverage to hub it would increase hub stress. My stock car pals fight this all the time when using stock spindles with reverse offset wheels. Moving tire contact patch outboard of hub increases load same way longer breaker bar increases torque.

I do not see it as dangerous at all.

[16ACE27]

Originally Posted by Muggs

Looking at the swap on front, I do not see an issue. The point of max hub load is still close to original design.

If wheel offset was too far out adding leverage to hub it would increase hub stress. My stock car pals fight this all the time when using stock spindles with reverse offset wheels. Moving tire contact patch outboard of hub increases load same way longer breaker bar increases torque.

I do not see it as dangerous at all.

Yeah, except in this case; going from a DRW offset to a standard offset you are actually decreasing the "torque" on the spindle/bearings. Still waiting for the "Danger" part:

[gmtech16450yz]

Originally Posted by Chance

Insanely dangerous
...blah blah blah...

I love you too Chance.

Unfortunately you lack an understanding of physics, practical experience and extensive training on the subject, knowing how to properly ask a question or show concern, and on top of all that, you live in an RV forum and you don't even own an RV.

lol. hahahahahaha.




.

[Long & Winding road]

Originally Posted by Chance

Insanely dangerous


Installing SRW wheels on a DRW front hub is going to get you killed, or worse yet, get some innocent person killed.

Why is it dangerous? Because of the extra leverage on the stock hub or suspension? It might make a difference - IDK.

Or for another reason that I cant think of?

Just want to know (for myself) and to point this out to someone thinking of doing the same mod. Any of our mods could be dangerous so it is on the owner to know what they are getting into. Saftey is number one.

I have put offset wheels with much larger tires on my 92 Jeep Wrangler that I owned for 25 years. They sticks out about 2 inches from the factory flares but is about 4 - 4.5 inches wider than factory and I never had a problem. I have Taking it off road several times (and its had some air time) and I never had a problem. But the RV is much heaver (Not air time for my RV - LOL).

I just like to know both side of this project - no arguments please.

[Chance]

Originally Posted by gmtech16450yz

I love you too Chance.

Unfortunately you lack an understanding of physics, practical experience and extensive training on the subject, knowing how to properly ask a question or show concern, and on top of all that, you live in an RV forum and you don't even own an RV.

lol. hahahahahaha.




.

So what, do you actually think someone has to jump off the Empire State Building first to know that it won’t end well? That logic is ridiculous.

And if presently owning an RV makes anyone an expert, why are there so many “OWNERS” constantly asking for help on all kinds of issues? That logic is also ridiculously stupid. Do all RV repairmen have to own RVs? Do they have to own the same kind they fix? Give me a break.

And for what it’s worth, I’ve owned both DRW and SRW E-Series RVs and have worked on them myself, including replacement of brakes, hubs, bearings, etc. As a mechanical engineer I don’t only know theory, I know this kind of stuff in practice also.

Besides, you have never shown that you actually understand physics at all. Period. You make a lot of claims, but that’s about it. In this case you’ve crossed a line by promoting a horrendous idea that’s dangerous and will get people hurt or worse. Mechanical engineers do understand physics, and I feel responsible to protect the safety of those who don’t know any better and can’t tell the difference.

And to be clear, just because you drive it around the block doesn’t make it safe. Just like poorly-designed hitches that broke after tens of thousands of miles, your accident may come later.

Do you really think that if it was that easy to widen the front track of a truck without compromising safety, that Ford wouldn’t simply change wheel offset to get what they want instead of designing a wider track front axle at a much higher cost?

I’m honestly surprised that the Alcoa vendor sold you the wheels at all if they knew your plans. Apparently their greed was stronger than their common sense.

Funny that I knew what would happen for trying to help you stay safe. You’re welcome anyway.

[16ACE27]

Originally Posted by Chance

So what, do you actually think someone has to jump off the Empire State Building first to know that it won’t end well? That logic is ridiculous.

And if presently owning an RV makes anyone an expert, why are there so many “OWNERS” constantly asking for help on all kinds of issues? That logic is also ridiculously stupid. Do all RV repairmen have to own RVs? Do they have to own the same kind they fix? Give me a break.

And for what it’s worth, I’ve owned both DRW and SRW E-Series RVs and have worked on them myself, including replacement of brakes, hubs, bearings, etc. As a mechanical engineer I don’t only know theory, I know this kind of stuff in practice also.

Besides, you have never shown that you actually understand physics at all. Period. You make a lot of claims, but that’s about it. In this case you’ve crossed a line by promoting a horrendous idea that’s dangerous and will get people hurt or worse. Mechanical engineers do understand physics, and I feel responsible to protect the safety of those who don’t know any better and can’t tell the difference.

And to be clear, just because you drive it around the block doesn’t make it safe. Just like poorly-designed hitches that broke after tens of thousands of miles, your accident may come later.

Do you really think that if it was that easy to widen the front track of a truck without compromising safety, that Ford wouldn’t simply change wheel offset to get what they want instead of designing a wider track front axle at a much higher cost?

I’m honestly surprised that the Alcoa vendor sold you the wheels at all if they knew your plans. Apparently their greed was stronger than their common sense.

Funny that I knew what would happen for trying to help you stay safe. You’re welcome anyway.

And the reason you think it is unsafe is............................?

All that typing and you still haven't answered the question of WHY you think it's unsafe. Please enlighten the class.

You may have the Engineering Degree but I guarantee you GMTECH has been around the block numerous times with all vehicle systems. To be a good auto tech you have to understand and troubleshoot
Mechanical Systems
Static and Dynamic Fluid Systems
HVAC Systems
Hydraulic Systems
Electrical Systems
Electronic Systems
etc, etc.

He has done nothing more than what hot rod'ers and racers have done for decades - improve upon the manufacturer's product.

If anything I would say his modifications have made the MH safer:

Wider Stance - Safer; Does this really need explaining?
Bigger Tires/Wheels - Safer; more safety margin to load capacity
Less Offset - Less Wear on spindles/bearings - Safer

So please enlighten the class why you made such a dramatic less safe claim.

[fhenn]

Let Not get too nasty or we have to make this thread go away

[Chance]

Originally Posted by Tfryman

And the reason you think it is unsafe is............................?

....cut.....

Moving a front wheel 5 inches outboard adversely affects both stresses and handling, and those who don’t see it on their own aren’t going to understand a technical answer regardless; so why bother with details, calculations, etc. Sorry but it’s true. And we’re talking about marginal motorhomes with 5,000-pound-rated axles often loaded to over 90%, and with poor handling to start with. There’s not much room for making matters worse.

A better argument is that no truck company, whether Ford, GM, FCA, Freightliner, Volvo, etc., does this. Nor would they ever for obvious reasons. The evidence is there for anyone to see on our highways.

No matter what I’d answer, you’re not going to believe me anyway. You’ve made that clear. I suggest you do your own research on the Internet to see why OEMs have worked so hard to bring wheels inboard over the last 50 years or so, probably longer. I know for a fact that no truck (or car) has been designed and built that way by proffessionals during my lifetime.




By the way, do you guys realize that the amount of change he’s incorporated to front suspension is essentially the same as if we took a SRW van or truck and bolted a DRW wheel sticking out? Half the tire would be beyond the front fender.

[gmtech16450yz]

Originally Posted by fhenn

Let Not get too nasty or we have to make this thread go away

Please don't do that ok? I'm not going to get into a battle with Chance. He'd like nothing better than to have my thread deleted. Again, I ask that you leave the thread up and hopefully he'll go away quietly.

[fhenn]

not yet but am having to keep a watch on it

[Chance]

Originally Posted by gmtech16450yz

Please don't do that ok? I'm not going to get into a battle with Chance. He'd like nothing better than to have my thread deleted. Again, I ask that you leave the thread up and hopefully he'll go away quietly.

Not true at all. I have no interest in getting thread deleted — most of what you’ve done looks great. Censoring information isn’t the solution in my opinion. Besides, threads normally get deleted because of personal attacks, not for the content that is presented in a civil manner.

I simply warned you and others of what I see as a serious safety issue. I had promised myself to ignore you completely, but I can’t do that in good conscience when it involves safety.

Have a nice day.

[Muggs]

Originally Posted by Chance

By the way, do you guys realize that the amount of change he’s incorporated to front suspension is essentially the same as if we took a SRW van or truck and bolted a DRW wheel sticking out? Half the tire would be beyond the front fender.

Yes, the first thing I looked for was leverage on front hub. If he had in fact bolted a DRW backwards on front hub, I would see that as possibly unsafe, the tires contact patch would be outside hub face without support from inner tire.

Looking at what he has actually done, I really do not see issue at all. To me it looks to be in an acceptable range in relation to hub face without adding significant amount of added stress. The tire is close enough to directly below the hub face. He explained the offset change in his opening paragraph.

Looks fine to me. I like the added safety margin of the higher load capacity tires. I am curious how the guy who went to commercial grade tires made out as well.

[Chance]

Originally Posted by Muggs

Yes, the first thing I looked for was leverage on front hub. If he had in fact bolted a DRW backwards on front hub, I would see that as possibly unsafe, the tires contact patch would be outside hub face without support from inner tire.

Looking at what he has actually done, I really do not see issue at all. To me it looks to be in an acceptable range in relation to hub face without adding significant amount of added stress. The tire is close enough to directly below the hub face. He explained the offset change in his opening paragraph.

Looks fine to me. I like the added safety margin of the higher load capacity tires. I am curious how the guy who went to commercial grade tires made out as well.

I’m certainly open to a civil technical discussion.

I'm not sure what combination you mean exactly since there are two major types of hubs and two types of wheels. According to both Ford and Alcoa specifications, the difference in offset is approximately 5 inches.

Before starting, it should be noted that Ford specs for E-Series list the same front track width at 69.4 inches whether it’s a SRW or DRW chassis. Both use a 5,000-pound front axle.

For clarity, I want to use a couple of pictures to make certain we are on same page. I can only post one at a time though.

This shows the type of front brake rotor hub used on SRW chassis (may not be exact part). When combined with SRW wheel (that has minimal offset), the track width ends up at 69.4 inches. This is type of hub I have presently.

[Chance]

When Ford (and most other manufacturers) use Dual Rear Wheels, they install a front hub that normally extends out the same amount as the difference in wheel offsets so the track, and therefore steering geometry, remains the same. Relative to suspension, the tire will end up exactly in same location on the E-Series chassis. Again, this may not be a Ford part but represents DRW hub.

This type is what comes on Axis/Vegas, and can be seen in picture he posted.

[Chance]

When you mount a SRW wheel on a DRW hub, the tire will be moved outward that 5 inches or so that is the difference in hub design. These hubs were not designed to be used with SRW wheels.

When used with correct wheel for the hub, the bearings, spindle, etc. can’t tell the difference (stresses are handled and cancel out within wheel and hub extension). When you use SRW wheel with DRW hub, and move tire 5 inches outboard, the stresses on bearings (particularly the smaller bearing at end of spindle) and on spindle goes up significantly.


If you were to install a DRW wheel backwards on a DRW hub (not what he’s done), it would move the front wheel out over 10 inches per side. I’m not sure if that’s what you were refering to in your first paragraph that I highlighted.

[Long & Winding road]

So if one were to purchase the correct rim (but maybe taller) that was like one inch wider and offset to the outside one inch (if not rubbing fenders) the OEM hub could handle this since its not such a dramatic change?

Or if there was an aftermarket hub that was stronger and had larger bearing one would be Okay??

[gmtech16450yz]

You know what's so interesting to me? The human nature part of this. I've been on a ton of forums since the days of newsgroups and chat rooms. Every forum is the same. They always have the exact same set of characters.

In this case, it's the guy who did a brake job in his driveway once, trying to tell the guy who's put a wrench to over 88,000 vehicles over his 40 year career that he's gonna "save" all of us from the imminent danger caused by this reckless person.

It's ok, I'm used to it. I've learned to not engage, it's really not worth it. I'm posting this to hopefully put this whole thread to rest. For those that care, what I did is perfectly safe. Is it within design specs? Of course not, that's the whole point of modifying ANYTHING. That's the reason huge industries, companies and organizations like SEMA exist to support innovation and discoveries. If it wasn't for people thinking outside the box, our entire being as a civilization would be stagnant and as ignorant as the cave men were.

Of course what I did isn't recommended by Ford or whoever. What I've done gutting the entire dash and front cap on the Vegas wasn't recommended or supported by Thor either. Either was what I did to the air conditioners lately. Hmmm, it seems to me I was also told on here that there's nothing to be gained by modifying the Coleman air conditioners and if they could work better, Coleman would have built them that way. lol. Again, if you believe that, we ALL cease to learn and evolve. I've lived my entire life with the realization that NOTHING is black and white. There are shades of grey in everything, even in engineering. The best engineers in history have been the ones that understand the rules, but realize that rules are meant to be broken. The ones that think everything is black and white and always lives within the "rules", will never make a new discovery on their own. That's boring. haha.

I'll leave a link at the bottom of this. Click on it and notice how many people loved what I did and posted "likes" to the thread. It's what I originally said about all forums being the same. The guy on that forum is "Navy Lifer". His thing is all about bolt circle differences between metric and standard nomenclature. Whenever anyone tries to put certain wheels on certain cars, he jumps into the thread to tell everyone they're all gonna die. lol. Never mind the fact that literally hundreds of thousands of cars around the world are driving around with what he says is wrong. It's simply a matter of black and white thinking. If the numbers don't match, it will not work. What good engineers realize though is the numbers will NEVER match if you take them down to a certain level. That's because the world isn't perfect.

What I did to MY RV isn't perfect. Neither am I. But the chances that it's going to kill me or my family or anyone else on the road are slim. The chances of being killed on the road for a million other reasons are FAR more likely. The chances me, my family or others on the road would be killed if I DIDN'T modify or fix all the f'd up stuff on this Thor Vegas were WAY HIGHER!

Déjà vu...

https://www.ssforums.com/forum/wheel...305s-back.html

(Wow, I forgot about post 17! That was a good one. lol.)


(hasn't killed me yet)