Status of SRW conversions for Fuso's in the US?
- Thread starter doubleb
- Start date
Bandicoot
Adventurer
Fuso Australia happy with Super singles on Canter 4WD
If you look at the Fuso Canter Australia official web site (see http://www.fuso.com.au/Article.aspx?ID=70&AspxAutoDetectCookieSupport=1[/URL]), Fuso is prepared to boast about the EarthCruiser (built on Canter) and specifically notes the "...Earth Cruiser’s claim to fame along with a suspension purpose-built around a single fat rear tyre that enables it to go off-road...", i.e. super singles. (my emphasis)
So it seems difficult to believe Fuso has much difficulty with super singles if properly engineered. However, perhaps as with many big organisations, the left hand of Fuso (down here) doesn't know what the right hand is doing (up North), etc.
In addition, super singles seem to have been on Canters in Oz for some time now with no axle or bearing problems so far as I'm aware at this point in time.
Bandicoot
If you look at the Fuso Canter Australia official web site (see http://www.fuso.com.au/Article.aspx?ID=70&AspxAutoDetectCookieSupport=1[/URL]), Fuso is prepared to boast about the EarthCruiser (built on Canter) and specifically notes the "...Earth Cruiser’s claim to fame along with a suspension purpose-built around a single fat rear tyre that enables it to go off-road...", i.e. super singles. (my emphasis)
So it seems difficult to believe Fuso has much difficulty with super singles if properly engineered. However, perhaps as with many big organisations, the left hand of Fuso (down here) doesn't know what the right hand is doing (up North), etc.
In addition, super singles seem to have been on Canters in Oz for some time now with no axle or bearing problems so far as I'm aware at this point in time.
Bandicoot
dakar rallys
hello all
here's one site and then check u-tube under dakar rallys and enjoy all the great video's, awsome stuff. be warned, you might be glued to your scrren for a couple of days ; )
http://thedakar.blogspot.com/2009/11/truckcatergory-in-dakar-insane.html
cheers lehel and laura
hello all
here's one site and then check u-tube under dakar rallys and enjoy all the great video's, awsome stuff. be warned, you might be glued to your scrren for a couple of days ; )
http://thedakar.blogspot.com/2009/11/truckcatergory-in-dakar-insane.html
cheers lehel and laura
ntsqd
Heretic Car Camper
I think that I'm missing something here. With DRW's presumably the wheel offset is the same for both wheels mounted to a common wheel hub. That puts the normal average loading at the plane where the two wheels physically meet. I say "normal" because there's always the incidental case where one rear tire climbs up a curb, or similar, and momentarily lifts it's mate off the ground. So that plane is the design loading location for the wheel bearings.
If the SRW wheel is designed to place the center of the tire's contact patch in this same plane, then the wheel bearings and axle housing will know no difference in how they're loaded under normal driving.
When considering impact loadings or the curb/similar scenarios, the narrower tire of the SRW, compared to the effective width of a DRW system (inside sidewall of inside tire to outside sidewall of outside tire), will have less leverage against the wheel bearings. If anything I see that as needing less axle bearing, not more. Perhaps this too is CYA?
A DRW used in front actually has it's WMS spaced outwards to accommodate the extreme offset of the DRW type of wheel. When this is done with a spacer then going SRW wheels in the front is as simple as removing the spacer (witness GM 'duallys'). If not done with a spacer, then it could be more complicated and/or result in two different track widths - which isn't the end of the world. All GM pick-ups since at least the early 70's well into the 90's are built this way.
whatcharterboat
Supporting Sponsor, Overland Certified OC0018
Hey guys Merry Xmas and a happy new year. Have been away camping for a couple of weeks and just dropped home to resupply and check some emails.
I know this thread was aimed at "SRW for Fuso's in North America" but thought I could add something anyway as we have put an enormous amount of time and money into developing SRW conversions here in Oz. Something my boss started way, way back in the '80's I think. Well into the hundreds of conversions now anyway. One of our customers is on his 29th FG with SRW so that must say something about whether or not they work in the long term.
The engineering issue is not side loads as NTSQD has tried to explain. Standard FG bearings, hubs, etc are far more robust than many realise. And the similar Isuzu NPS's are even stronger again. No, the primary cause for concern is the reduced brake performance that happens when you increase the rolling diameter of the wheels. Now FG's arrive here from Japan fitted with tyres that are about 790mm diameter. Most SRW conversions will use tyres of between 875mm and 930mm. Some are even over a 1000mm diameter. This is what needs to be proven. Will they still stop effectively?
In Australia trucks have to meet very tight brake performance criteria and I know there is a few pics of us doing this brake performance testing in the other threads here. The point is that even with the larger diameter wheels, they will still meet the Australian standard (after a few simple mods). BTW This technically applies to trucks with a GVM over 4.5ton in Oz. I imagine North America standards are similar. I know some of our ADR's are tougher but this doesn't mean brake performance regulations will be also.
Also the other minor legal issue here is speedo accuracy but this is also easily remedied.
While I'm at it, (cause someone asked about longterm effects), I should also say that the shape of the 5 stud FG rear brake hub will cause the standard FG wheel centres to crack after time in a SRW situation unless a spacer is used to simulate the missing inner dual wheel. The 6 stud FG rear hubs are not a problem here in Oz as far as we can tell. Most of the SRW conversions done now are running 19'5" wheels which have very thick centres and this is also another way around this issue of the hub shape on the older models(Lehel's wheels for example).
Load ratings of the wheels themselves is probably the last thing worth noting but probably the transport authorities would be far more concerned about that than Fuso. Do the wheels meet the torsional cornering tests? There isn't even a machine in Oz to check truck wheels but for it to be 100% approved shouldn't the wheels have an ISO test approval number stamped on them as the standard FG wheels do? Hey, maybe I'm going off track here. Again something we had to face but may not be required in North America.
OK Am going back to play in the mud for a few more days. Rain, rain go away......
I know this thread was aimed at "SRW for Fuso's in North America" but thought I could add something anyway as we have put an enormous amount of time and money into developing SRW conversions here in Oz. Something my boss started way, way back in the '80's I think. Well into the hundreds of conversions now anyway. One of our customers is on his 29th FG with SRW so that must say something about whether or not they work in the long term.
The engineering issue is not side loads as NTSQD has tried to explain. Standard FG bearings, hubs, etc are far more robust than many realise. And the similar Isuzu NPS's are even stronger again. No, the primary cause for concern is the reduced brake performance that happens when you increase the rolling diameter of the wheels. Now FG's arrive here from Japan fitted with tyres that are about 790mm diameter. Most SRW conversions will use tyres of between 875mm and 930mm. Some are even over a 1000mm diameter. This is what needs to be proven. Will they still stop effectively?
In Australia trucks have to meet very tight brake performance criteria and I know there is a few pics of us doing this brake performance testing in the other threads here. The point is that even with the larger diameter wheels, they will still meet the Australian standard (after a few simple mods). BTW This technically applies to trucks with a GVM over 4.5ton in Oz. I imagine North America standards are similar. I know some of our ADR's are tougher but this doesn't mean brake performance regulations will be also.
Also the other minor legal issue here is speedo accuracy but this is also easily remedied.
While I'm at it, (cause someone asked about longterm effects), I should also say that the shape of the 5 stud FG rear brake hub will cause the standard FG wheel centres to crack after time in a SRW situation unless a spacer is used to simulate the missing inner dual wheel. The 6 stud FG rear hubs are not a problem here in Oz as far as we can tell. Most of the SRW conversions done now are running 19'5" wheels which have very thick centres and this is also another way around this issue of the hub shape on the older models(Lehel's wheels for example).
Load ratings of the wheels themselves is probably the last thing worth noting but probably the transport authorities would be far more concerned about that than Fuso. Do the wheels meet the torsional cornering tests? There isn't even a machine in Oz to check truck wheels but for it to be 100% approved shouldn't the wheels have an ISO test approval number stamped on them as the standard FG wheels do? Hey, maybe I'm going off track here. Again something we had to face but may not be required in North America.
OK Am going back to play in the mud for a few more days. Rain, rain go away......
RSW -- OFFSET Disk wheels CANTER is ... - SRW
Hi,
I have somehow started to respond on another recent posting on Rear Single Wheels, however I feel this should be more practical:
On our CANTER 94 FG 538B, RHD, 24V, the difference in length between one half of the front axle (the longest) and one half of the rear axle is A=160 mm
We want to be able to reverse the wheels to use any wheel either on front or rear. It means that the sum of the offsets will have to catch up with A.
So approximately, the offset = A/2, ie 80 mm.
We should take into account the plate thickness PT but I believe it can be neglected.
However, if detailed formula is needed, and if I am not wrong:
positive offset = (A-PT)/2 positive = wheel over the hub - re front wheels
negative offset= (A+PT)/2 neg= wheel away from hub - re external rear w
Note that tech details-drawing are available on Advance Wheel Corp web site, check zDROP-CENTER.pdf
WARNING 1 - Fuso is not Canter 94... we are painfully going through this now, while in the USA, searching spares for our Canter.
That is why I gave the above formula, because one should not assume 80 mm is the right offset for a Fuso. One should measure one's truck.
However, we found that more data than the offset is needed... starting with max weight per wheel, etc...
WARNING 2 - since we are currently investigating SRW, here are some findings we hope useful when exchanging info on Fuso/Canter:
a- our Canter 94 has 5 lugs split rims, while a US Fuso I recently checked in the US has 6 lugs
b- bolt holes : the chanfer type has to be 2 sides (reverse use of wheels) and it is spherical in our Canter FG 538B 1994.
By the way, any kind Down Under help available data/confirmation re exact measures on a Canter ?
- bolt holes chanfer radius by chance ?
- bolt circle diameter ? 207 mm
- bolt hole diameter? 32.5 mm ? (unfortunately, it is the only detail I could read on Alan's kind post with a picture attached)
- pilot hole "bore hole" "hub hole" diameter ? 150 mm ?
We are currently trying to find a supplier, here, while visiting the US, and it is a bit of a catch 22: trying in that process to also optimize future disk wheels size (not decided yet) with any serious tires manufacturers offer, taking into account which brands/sizes are easily available in Latin America, our destination.
Regarding rim/tires diameter, Gary W who has travelled a lot in Latin America has strongly recommended us to avoid "half size", i.e. something + 1/2.
Since we have read many posts re the quality of "service" from a company in Stockton, CA, which seems to have made Fuso wheels, we believe it is wise we explore other options.
So, any input is most welcome especially if you happen to have already done SRW on a Canter. Please PM contact details so we can ask for a quote for wheels and for shipping.
If we finally find a good option outside the USA, able to do Fuso and Canter tubeless disk wheels, maybe we should consider to group with other Fuso/Canter happy owners in the US for price negociation and sharing shipping ? PM welcome.
Thanks,
Robert
www.kookynet.net
PS: winck to mates... never again shall I have a brekkie with my coldie sitting on the barbie ! :coffeedrink:
Hi,
I have somehow started to respond on another recent posting on Rear Single Wheels, however I feel this should be more practical:
On our CANTER 94 FG 538B, RHD, 24V, the difference in length between one half of the front axle (the longest) and one half of the rear axle is A=160 mm
We want to be able to reverse the wheels to use any wheel either on front or rear. It means that the sum of the offsets will have to catch up with A.
So approximately, the offset = A/2, ie 80 mm.
We should take into account the plate thickness PT but I believe it can be neglected.
However, if detailed formula is needed, and if I am not wrong:
positive offset = (A-PT)/2 positive = wheel over the hub - re front wheels
negative offset= (A+PT)/2 neg= wheel away from hub - re external rear w
Note that tech details-drawing are available on Advance Wheel Corp web site, check zDROP-CENTER.pdf
WARNING 1 - Fuso is not Canter 94... we are painfully going through this now, while in the USA, searching spares for our Canter.
That is why I gave the above formula, because one should not assume 80 mm is the right offset for a Fuso. One should measure one's truck.
However, we found that more data than the offset is needed... starting with max weight per wheel, etc...
WARNING 2 - since we are currently investigating SRW, here are some findings we hope useful when exchanging info on Fuso/Canter:
a- our Canter 94 has 5 lugs split rims, while a US Fuso I recently checked in the US has 6 lugs
b- bolt holes : the chanfer type has to be 2 sides (reverse use of wheels) and it is spherical in our Canter FG 538B 1994.
By the way, any kind Down Under help available data/confirmation re exact measures on a Canter ?
- bolt holes chanfer radius by chance ?
- bolt circle diameter ? 207 mm
- bolt hole diameter? 32.5 mm ? (unfortunately, it is the only detail I could read on Alan's kind post with a picture attached)
- pilot hole "bore hole" "hub hole" diameter ? 150 mm ?
We are currently trying to find a supplier, here, while visiting the US, and it is a bit of a catch 22: trying in that process to also optimize future disk wheels size (not decided yet) with any serious tires manufacturers offer, taking into account which brands/sizes are easily available in Latin America, our destination.
Regarding rim/tires diameter, Gary W who has travelled a lot in Latin America has strongly recommended us to avoid "half size", i.e. something + 1/2.
Since we have read many posts re the quality of "service" from a company in Stockton, CA, which seems to have made Fuso wheels, we believe it is wise we explore other options.
So, any input is most welcome especially if you happen to have already done SRW on a Canter. Please PM contact details so we can ask for a quote for wheels and for shipping.
If we finally find a good option outside the USA, able to do Fuso and Canter tubeless disk wheels, maybe we should consider to group with other Fuso/Canter happy owners in the US for price negociation and sharing shipping ? PM welcome.
Thanks,
Robert
www.kookynet.net
PS: winck to mates... never again shall I have a brekkie with my coldie sitting on the barbie ! :coffeedrink:
I think that for reasons of stability the SRW offset doesn't place the tire center in the same location as the DRW setup. The 14" rim is a lot narrower than two 8.25" rims set up as duals. Big trucks have a tendency to tip over on freeway ramps without narrowing their footprint.
mhiscox
Exp. Leader Emeritus
O.K., I hesitate to post this because, while I may have a few areas of expertise, axle engineering is certainly not one of them.
So let's agree from the start that I'm over my head and just passing on to you an edited version--I took at all the "you'll kill yourself" sort of stuff
--of what I got from Darrin Fink regarding the reason that he would not put single rear wheels on a Fuso FG camper for me. Take the information however you want, but I'm not competent to discuss it, and Darrin hasn't changed his mind in a near-decade of people trying to convince him, so respond with that in mind.
BTW, it's worth noting that Darrin's big Fuso FM-based campers have singles on their purpose-speced axles, so he is not opposed to the idea generally, just the idea of taking a relatively light-duty axle made for duals and using it with single rear wheels when the truck's manufacturer told him not to.
Hi, Mike:
A typical rear axle for duals is MUCH more narrow than a front axle. It's made for dual wheels, and the wheel end hardware (hub, bearings, etc.) is designed to be *mostly* radially loaded. When you throw just the outset dual on, the forces on the bearing (and the whole axle housing, for that matter) change. Now there's more leverage on the housing, and axial load on the bearing at the top and bottom, which it's not designed to take, mile after mile.
Here's a crude drawing...
It's not just vehicle manufacturers not supporting the conversion. Dana Corporation, for example, will ONLY allow a maximum of like 2.75" of outset on a heavy-duty housing axle, and they de-rate the capacity of that housing assembly when it is equipped with JUST 2.75" of outset. When I needed 5.25" of outset, to make my front and rear tires track together, they basically said, "Sorry. No can do. No warranty on that, no liability from us. We do NOT authorize anything over 2.75" at ANY weight capacity."
Anecdotally, there's evidence that the conversion works and lasts, especially with reduced axle loads. But it's still not a smart game to play, even with the odds in your favor. Throw in the liability, and as a manufacturer--especially in extremely litigious United States--we simply can't do it.
If you think you know more than the manufacturer of the chassis or its components, go right ahead with the conversion. But don't ***** if something happens.
Behind me, I have MFTA, MFTBC, Dana Corporation, Marmon-Herrington, and Fabco as "experts" on this, and it's reasonable to assume that they know what they are talking about. The question is not "Will it work?" or "How long will it last?" but rather is it smart to do from a safety and liability standpoint, and what recourse will you have if there's a problem?
Darrin L. Fink - President
Renaissance Universal Fabrication, Inc.
(d/b/a RUF, Inc.)
756 Wagonhound Rd.
Douglas, WY 82633
Tel: (307) 351-4772
eMail: darrin@ruf-inc.com
Web: http://www.ruf-inc.com/
As I said at the outset, I'm just providing this by way of explanation; make of it what you will. I will add, though, that I also ran a small business and I absolutely second what Darrin says about how no business with any assets would, at least in the United States, dare to go against the manufacturer's recommendations.
If you were driving a truck with singles Darrin put on and ANYTHING happened to that rear axle that caused injury or death, your attorneys, once they learned RUF had gone against Mitsubishi Fuso Trucks of America's engineers would sue Darrin for everything he had and would ever have. I believe the issues of liability for a "forbidden" modification mean that while many of us based in the US are personally willing and able to go against manufacturer's recommendations, businesses like RUF and MFTA can not.
So let's agree from the start that I'm over my head and just passing on to you an edited version--I took at all the "you'll kill yourself" sort of stuff
--of what I got from Darrin Fink regarding the reason that he would not put single rear wheels on a Fuso FG camper for me. Take the information however you want, but I'm not competent to discuss it, and Darrin hasn't changed his mind in a near-decade of people trying to convince him, so respond with that in mind.BTW, it's worth noting that Darrin's big Fuso FM-based campers have singles on their purpose-speced axles, so he is not opposed to the idea generally, just the idea of taking a relatively light-duty axle made for duals and using it with single rear wheels when the truck's manufacturer told him not to.
Hi, Mike:
A typical rear axle for duals is MUCH more narrow than a front axle. It's made for dual wheels, and the wheel end hardware (hub, bearings, etc.) is designed to be *mostly* radially loaded. When you throw just the outset dual on, the forces on the bearing (and the whole axle housing, for that matter) change. Now there's more leverage on the housing, and axial load on the bearing at the top and bottom, which it's not designed to take, mile after mile.
Here's a crude drawing...
It's not just vehicle manufacturers not supporting the conversion. Dana Corporation, for example, will ONLY allow a maximum of like 2.75" of outset on a heavy-duty housing axle, and they de-rate the capacity of that housing assembly when it is equipped with JUST 2.75" of outset. When I needed 5.25" of outset, to make my front and rear tires track together, they basically said, "Sorry. No can do. No warranty on that, no liability from us. We do NOT authorize anything over 2.75" at ANY weight capacity."
Anecdotally, there's evidence that the conversion works and lasts, especially with reduced axle loads. But it's still not a smart game to play, even with the odds in your favor. Throw in the liability, and as a manufacturer--especially in extremely litigious United States--we simply can't do it.
If you think you know more than the manufacturer of the chassis or its components, go right ahead with the conversion. But don't ***** if something happens.
Behind me, I have MFTA, MFTBC, Dana Corporation, Marmon-Herrington, and Fabco as "experts" on this, and it's reasonable to assume that they know what they are talking about. The question is not "Will it work?" or "How long will it last?" but rather is it smart to do from a safety and liability standpoint, and what recourse will you have if there's a problem?
Darrin L. Fink - President
Renaissance Universal Fabrication, Inc.
(d/b/a RUF, Inc.)
756 Wagonhound Rd.
Douglas, WY 82633
Tel: (307) 351-4772
eMail: darrin@ruf-inc.com
Web: http://www.ruf-inc.com/
As I said at the outset, I'm just providing this by way of explanation; make of it what you will. I will add, though, that I also ran a small business and I absolutely second what Darrin says about how no business with any assets would, at least in the United States, dare to go against the manufacturer's recommendations.
If you were driving a truck with singles Darrin put on and ANYTHING happened to that rear axle that caused injury or death, your attorneys, once they learned RUF had gone against Mitsubishi Fuso Trucks of America's engineers would sue Darrin for everything he had and would ever have. I believe the issues of liability for a "forbidden" modification mean that while many of us based in the US are personally willing and able to go against manufacturer's recommendations, businesses like RUF and MFTA can not.
ntsqd
Heretic Car Camper
Certainly using a single wheel with the std DRW offset at the rear, no matter how wide, would be bad no matter which way it was bolted on. Using a SRW with the correct offset would load the bearings no differently than with DRW's.
Interesting comment about braking vs. tire OD. I had kept that as a separate issue, but the reality is that both moves would probably happen simultaneously. Hum....
Re: SRW resulting in a narrower track width. My observation is that this is all over the map. Some OE's place the front tire track centered between the DRW tires. Other's place the front inline with either the inner or the outer rear tire. The only 4WD Fuso that I have available to look at is Bajaroad's, and it has already been converted so I've no idea what the Fuso layout is when stock. Assuming that the SRW wheels are built to locate the load properly with respect to the rear axle wheel bearings then those same wheels used up front potentially move the tire outboard and create more Scrub Radius while also moving the load outboard of the design position relative to the front wheel bearings.
Perhaps this is another reason that Fuso doesn't recommend it?
Interesting comment about braking vs. tire OD. I had kept that as a separate issue, but the reality is that both moves would probably happen simultaneously. Hum....
Re: SRW resulting in a narrower track width. My observation is that this is all over the map. Some OE's place the front tire track centered between the DRW tires. Other's place the front inline with either the inner or the outer rear tire. The only 4WD Fuso that I have available to look at is Bajaroad's, and it has already been converted so I've no idea what the Fuso layout is when stock. Assuming that the SRW wheels are built to locate the load properly with respect to the rear axle wheel bearings then those same wheels used up front potentially move the tire outboard and create more Scrub Radius while also moving the load outboard of the design position relative to the front wheel bearings.
Perhaps this is another reason that Fuso doesn't recommend it?
Fuso may be somewhat touchy about the subject since fatalities related to wheel separations back in 2002 led to the their being banned in 38 prefectures in Japan and the eventual imprisonment of several executives. This likely is the reason that Daimler took over the portion of Fuso that they didn't already own.
whatcharterboat
Supporting Sponsor, Overland Certified OC0018
Hey young Thom. How are ya?
For an FG to end up with front and rear tracks the same (and use the same offset wheels all round) >> the front rims have to come out and the rear wheel turned around (someone called it "flip-flop") will end up further inboard than the OE outer rim. However the new resulting front / rear track will now be wider than the average of the original front and rear tracks combined. Just that someone was worried they would not be as stable cornering ????? Not so.
Yes again about the correct offset, however I should say that many of the older SRW conversions around here running Michelin XZL's don't even bother with special wheels having the optimum offset and simply run a single OE rim on the rear. No problem that I've ever heard of regarding the bearings (ever) and some of these run in extreme offroad situations non-stop. eg. the same conditions that would have them replacing shackle rubbers every 2 weeks. Of course running OE wheels results in quite different front and rear tracks which isn't really the best thing offfroad, particularly soft sand.
Hey. Just want to stress that what we do here may not apply to you guys in the US at all. Only throwing my 2 cents in. If someone of Darrin's caliber has concerns I'm sure they are valid over there.
mhiscox
Exp. Leader Emeritus
Thanks for that understanding, John. Darrin knows full well that the FG SRW conversions--when done by people showing talent and care--are generally working out fine. His crucial point, and I believe it would apply equally to changes in fuel tanks, steering, tires, brakes, etc., is that as a converter in the litigous United States, he's not permitted to do modifications not approved by the factory. In this way, he's no different than the guy who mounts a furniture van box . . . if he doesn't do it the way he was instructed to do it by the manufacturer, he can be held responsible if the box falls off and hurts someone.
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