Wheel Spacers – Good or Bad?
- Thread starter Wohni
- Start date
dieselcruiserhead
16 Years on ExPo. Whoa!!
When I ran them in the front I found the wheel kind of bounced around a little and you could really "feel" the spacer. Also the spacer changes the quantity the wheel itself moves for steering, so it is not perfect but is definitely a decent solution. The Mini truck guys use them often. My rec is to use the smallest size as possible, but you can use them. I perfer to consider them a reasonable long-term temporary solution. In the front with my FJ40 axle I switched to a 60 series axle (including outboarding the spring hangers). Took a couple days but 100% worth it IMO.
crawler#976
Expedition Leader
I used steel spacers on a purpose built rock crawler to increase the track width both front (2-1/4" bolt on) and rear (3/4" over longer studs). The truck also had 45,000 miles use as a daily driver.
I noticed a decrease in brake performance especially on the front due to the added mass.
The front came loose frequently enough that I added them to my list of "after every run" maintenance list. Along with steering arm studs, I put a wrench on them after every hard trail run. The first set of aluminum spacers became galled up badly after the constant tightening routine. If the aluminum spacers had steel inserts, they would have been much better units.
Front wheel bearings needed adjusting more frequently, had to be replaced annually, and I had the rear sealed bearings fail on both sides.
Again, this isn't normal use by any means. I was driving a dual spooled truck geared at 109:1.
Mark
I noticed a decrease in brake performance especially on the front due to the added mass.
The front came loose frequently enough that I added them to my list of "after every run" maintenance list. Along with steering arm studs, I put a wrench on them after every hard trail run. The first set of aluminum spacers became galled up badly after the constant tightening routine. If the aluminum spacers had steel inserts, they would have been much better units.
Front wheel bearings needed adjusting more frequently, had to be replaced annually, and I had the rear sealed bearings fail on both sides.
Again, this isn't normal use by any means. I was driving a dual spooled truck geared at 109:1.
Mark
ntsqd
Heretic Car Camper
I make the assumption that we are discussing spacers as used in Overlanding types of use, and not on some sort of trailered buggy.
I see this subject not as any empirical evidence proves it right, but more like scientific theory's where one piece of contrary evidence proves it invalid. From: http://www.expeditionportal.com/forum/showpost.php?p=286259&postcount=20
The issue of an aluminum spacer is not it's strength. It is that aluminum, unlike low carbon steel, has a finite fatigue life. Those that mention how many thousands of miles or years that they have on their spacers are closer to a failure now than when brand new. More time in service means that they are closer to the coming failure.
What will determine when the spacer fails (it will eventually fail) is how highly loaded it is and how long it is in service. Unfortunately there is no simple way to predict when the failure will happen because it is too dependent on how good a job the designer did in reducing the internal stress' and how good a job the mfg shop did in following the design, and also how perfect the blank they started with was (Nothing is ever perfect!).
If the Mfg has done all of their homework they know what the internal stress' are and, based on Fatigue Life calculations for the alloy used, also know what the maximum expected service life should be. None of this will account for an unknown imperfection in the metal, but it is a reasonable indicator of when the spacers should be replaced. Not quite as "plug and play" as saying "a loading of X lbs. has a service life of Y thousand miles" since the loading usually varies over time. Obviously, the lighter the loading, the longer the service life will be. In a very lightly loaded case the service life may effectively be infinite, but absent mfg's guidelines or published stress data how do you know?
The actual position of the WMS is insignificant to the loading of the wheel bearings (& other joints if so equipped). Where the contact patch centerline is relative to the WMS is the important item. Witness a U.S. 2WD dually pick-up. The front axle WMS is way outside of the contact patch center, but the bearings are not.
In the case of dual rear tires the need for both tires to be operational becomes paramount less the now dislocated contact patch center be moved an exceptional distance away from being centered on the bearings.
As to the choice of AR 589's, I know of one set of 6 that saw 10 plus years of regular pre-run and chase service in Baja and in the US. Once that truck was raced because the desert race truck was not ready. Those wheels were retired when one did finally develop a crack. The one mentioned with the problem is a classic example of an unknown imperfection causing a catastrophic result. Empirical evidence is handy, but in most cases one can find counter evidence to any single claim. The percentage of failures is what matters in this sort of analysis.
I see this subject not as any empirical evidence proves it right, but more like scientific theory's where one piece of contrary evidence proves it invalid. From: http://www.expeditionportal.com/forum/showpost.php?p=286259&postcount=20
For me the cost of a single failure is too high. What if there had been an occupied child's seat in that Ranger's passenger side?Grim Reaper said:
The issue of an aluminum spacer is not it's strength. It is that aluminum, unlike low carbon steel, has a finite fatigue life. Those that mention how many thousands of miles or years that they have on their spacers are closer to a failure now than when brand new. More time in service means that they are closer to the coming failure.
What will determine when the spacer fails (it will eventually fail) is how highly loaded it is and how long it is in service. Unfortunately there is no simple way to predict when the failure will happen because it is too dependent on how good a job the designer did in reducing the internal stress' and how good a job the mfg shop did in following the design, and also how perfect the blank they started with was (Nothing is ever perfect!).
If the Mfg has done all of their homework they know what the internal stress' are and, based on Fatigue Life calculations for the alloy used, also know what the maximum expected service life should be. None of this will account for an unknown imperfection in the metal, but it is a reasonable indicator of when the spacers should be replaced. Not quite as "plug and play" as saying "a loading of X lbs. has a service life of Y thousand miles" since the loading usually varies over time. Obviously, the lighter the loading, the longer the service life will be. In a very lightly loaded case the service life may effectively be infinite, but absent mfg's guidelines or published stress data how do you know?
The actual position of the WMS is insignificant to the loading of the wheel bearings (& other joints if so equipped). Where the contact patch centerline is relative to the WMS is the important item. Witness a U.S. 2WD dually pick-up. The front axle WMS is way outside of the contact patch center, but the bearings are not.
In the case of dual rear tires the need for both tires to be operational becomes paramount less the now dislocated contact patch center be moved an exceptional distance away from being centered on the bearings.
As to the choice of AR 589's, I know of one set of 6 that saw 10 plus years of regular pre-run and chase service in Baja and in the US. Once that truck was raced because the desert race truck was not ready. Those wheels were retired when one did finally develop a crack. The one mentioned with the problem is a classic example of an unknown imperfection causing a catastrophic result. Empirical evidence is handy, but in most cases one can find counter evidence to any single claim. The percentage of failures is what matters in this sort of analysis.
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lowenbrau
Explorer
The first post has a link to what looks like a high quality steel spacer. I believe that, especially on the rear axle, will be fine to use. Every domestic dually in the world has a similar apparatus on its front axle. The problem of loose wheel spacers comes from using aluminum in an application that it is not best suited for. Aluminum wheels rarely come with cone shaped lug nuts but aluminum wheel spacers have to. I believe steel is a much better choice for this application but it adds rotating mass.
I have 60 series axles under my BJ74 and still need the additional width of IFS hubs in the front and rear spacers in order to run 5.5" BS FGL wheels. I'm planning to do away with the spacers once I get a lathe up and running and can produce or modify some suitable wider stance rear hubs. I probably should have just used 80 series axles to begin with.
I have 60 series axles under my BJ74 and still need the additional width of IFS hubs in the front and rear spacers in order to run 5.5" BS FGL wheels. I'm planning to do away with the spacers once I get a lathe up and running and can produce or modify some suitable wider stance rear hubs. I probably should have just used 80 series axles to begin with.
ntsqd,
you just scared the living crap out of me ... my wife rolled our VW Bus 2 years ago, following a tyre burst in the middle of nowhere 50kms away from her sister's farm - I was 8500kms away in Germany when it happened ... my then 1.5 and 2.5 year old boys were in there - nobody was hurt, the car was obviously a write-off ... so much about why I keep on being a pain about this subject, I would like to get it right - and just when I thought I had it, well ...
anywho, I have worked with metals for some time in my life and believe that I have some sort of savvy understanding/sense when it comes to their respective properties ... from the start, and that's why I specifically asked the dude about his spacers, I considered aluminum somewhat 'disagreeable' without being able to scientifically substantiate this, the advantage of less un-sprung mass is obvious though
however, surely there must be a suitable kind of metal/steel and specialised fabricators/fitters/turners who are able to machine a decent set of spacers out of the same ... no? ... we fly aircraft seating more than 600 people and build bridges spanning kilometers by hanging on cables ... yes I agree, even those engineering marvels and/or anything can/will break if abused/misused for long enough ... but then ...
you just scared the living crap out of me ... my wife rolled our VW Bus 2 years ago, following a tyre burst in the middle of nowhere 50kms away from her sister's farm - I was 8500kms away in Germany when it happened ... my then 1.5 and 2.5 year old boys were in there - nobody was hurt, the car was obviously a write-off ... so much about why I keep on being a pain about this subject, I would like to get it right - and just when I thought I had it, well ...
anywho, I have worked with metals for some time in my life and believe that I have some sort of savvy understanding/sense when it comes to their respective properties ... from the start, and that's why I specifically asked the dude about his spacers, I considered aluminum somewhat 'disagreeable' without being able to scientifically substantiate this, the advantage of less un-sprung mass is obvious though
however, surely there must be a suitable kind of metal/steel and specialised fabricators/fitters/turners who are able to machine a decent set of spacers out of the same ... no? ... we fly aircraft seating more than 600 people and build bridges spanning kilometers by hanging on cables ... yes I agree, even those engineering marvels and/or anything can/will break if abused/misused for long enough ... but then ...
the dude
Adventurer
after you've wiped and cleaned up, remember that everything can fail. I have read stories of tie rods failing, tires failing (as in your case) , steering boxes failing ect. It doesn't mean I will never drive. If that was the case for all things, I would never leave the house.
You may consider AL wheel spacers a wear item. That's why I got mine check this year. I have about 70 000km on them. I am sure there are tens of thousands of vehicles with spacer on them and would consider them a safe option.
If it makes you feel better throw them out every X amount of KM. Or look for a steel alternative.
You may consider AL wheel spacers a wear item. That's why I got mine check this year. I have about 70 000km on them. I am sure there are tens of thousands of vehicles with spacer on them and would consider them a safe option.
If it makes you feel better throw them out every X amount of KM. Or look for a steel alternative.
FYI:
____________________________________________________________
G'day Tommy
Spacers are made from steel, benefits of having the track the same are very important if traversing on soft ground.
Fuel ecomomy plus the drag on the truck and camper making new tracks with uneven footprints is pretty obvious i think.
A wider track makes for a more stable vehicle / camper all comes down to how wide the tracks are you are driving on.
Thanks
Rhino
____________________________________________________________
(reply to inquiry from sales@snakeracing.com.au)
____________________________________________________________
G'day Tommy
Spacers are made from steel, benefits of having the track the same are very important if traversing on soft ground.
Fuel ecomomy plus the drag on the truck and camper making new tracks with uneven footprints is pretty obvious i think.
A wider track makes for a more stable vehicle / camper all comes down to how wide the tracks are you are driving on.
Thanks
Rhino
____________________________________________________________
(reply to inquiry from sales@snakeracing.com.au)
ntsqd
Heretic Car Camper
The important point to remember about those (steel/iron) spacers used on the front of U.S. dually trucks is where the center of the tire's contact patch is. When you move that center point in or out excessively the first thing that really gets worked is the spacer. Those dually's have the spacer because of the deep offset dually wheel. The contact patch center is in a place where the leverage against the spacer is almost non-existent even though the Wheel Mount Surface (WMS) is way outboard of the center of the contact patch. The deep offset of the wheel cancels out the spacer.
Contrast that with how (aluminum) spacers are used, in particular, on Toyota axled rock crawlers. Their contact patch center is radically moved from stock and has a huge lever to work the spacer with.
It is of paramount importance that it be recognized that the location of the WMS is not, by itself, an important factor in the whole picture. Where the center of the tire's contact patch is relative to the original wheel hub's WMS is the important feature.
A gross illustration would be the above dually truck example. With both tires in place the center of the "contact patch" is halfway between the two actual contact patches, and directly under the wheel hub's WMS. Perhaps a useful mental picture is to think of this as an upside down teeter-totter with the seats being the contact patches and the pivot point being the WMS.
Now picture removing the inner rear tire on one side. With one tire gone the contact patch center has been radically moved away from the intended point and the leverage on the wheel bearings is huge even though there is no spacer involved at all!
I think the best solution is a wider axle though I recognize that this may or may not be the most economically or physically viable option. If an aluminum spacer is the only realistic option, then I highly suggest doing as suggested and considering them a wear item. If you go this direction a set number of miles/km's should be set and then regardless of how good they appear to be they get tossed. The only alternative would be regular X-Ray inspection. I suspect that the cost of such an inspection would be close enough to the cost of new spacers that it wouldn't make much sense to do this.
Something yet to be touched on, and I do not recall if it is applicable or not, is a semi-float rear axle design. These only have one wheel bearing and it starts out with a fair amount of leverage on it. Adding a spacer only makes this worse. The bad part is that what will most likely fail, probably even before the spacer, is the axle flange. Having lived through two axle flange failures (with no spacers!) I would not consider the use of a spacer on a flanged axle to be safe for use on any public roads unless the spacer is only making up for a deep offset wheel and the overall result is that the tire contact patch center is in the stock location.
Whether you decide to use a spacer or to not use one is, obviously, up to you. I just want to see the decision be one informed with Engineering facts based opinion rather than Internet speculation. That the spacers that you've found are made of steel is a bonus from a safety perspective. Do they have a picture of them on-line?
Contrast that with how (aluminum) spacers are used, in particular, on Toyota axled rock crawlers. Their contact patch center is radically moved from stock and has a huge lever to work the spacer with.
It is of paramount importance that it be recognized that the location of the WMS is not, by itself, an important factor in the whole picture. Where the center of the tire's contact patch is relative to the original wheel hub's WMS is the important feature.
A gross illustration would be the above dually truck example. With both tires in place the center of the "contact patch" is halfway between the two actual contact patches, and directly under the wheel hub's WMS. Perhaps a useful mental picture is to think of this as an upside down teeter-totter with the seats being the contact patches and the pivot point being the WMS.
Now picture removing the inner rear tire on one side. With one tire gone the contact patch center has been radically moved away from the intended point and the leverage on the wheel bearings is huge even though there is no spacer involved at all!
I think the best solution is a wider axle though I recognize that this may or may not be the most economically or physically viable option. If an aluminum spacer is the only realistic option, then I highly suggest doing as suggested and considering them a wear item. If you go this direction a set number of miles/km's should be set and then regardless of how good they appear to be they get tossed. The only alternative would be regular X-Ray inspection. I suspect that the cost of such an inspection would be close enough to the cost of new spacers that it wouldn't make much sense to do this.
Something yet to be touched on, and I do not recall if it is applicable or not, is a semi-float rear axle design. These only have one wheel bearing and it starts out with a fair amount of leverage on it. Adding a spacer only makes this worse. The bad part is that what will most likely fail, probably even before the spacer, is the axle flange. Having lived through two axle flange failures (with no spacers!) I would not consider the use of a spacer on a flanged axle to be safe for use on any public roads unless the spacer is only making up for a deep offset wheel and the overall result is that the tire contact patch center is in the stock location.
Whether you decide to use a spacer or to not use one is, obviously, up to you. I just want to see the decision be one informed with Engineering facts based opinion rather than Internet speculation. That the spacers that you've found are made of steel is a bonus from a safety perspective. Do they have a picture of them on-line?
These are the mentioned wheel spacers
... I had a bit of e-mail ping pong with the guys and apparently they are doing this for 15 years without failure/breakage (military, nascar, drift-cars, etc.)
Remember from the initial post, I will only require spacers in the back, as the front axle is the wider one ... I would probably not even consider spacers if it would be the front we are talking about
... I had a bit of e-mail ping pong with the guys and apparently they are doing this for 15 years without failure/breakage (military, nascar, drift-cars, etc.)
Remember from the initial post, I will only require spacers in the back, as the front axle is the wider one ... I would probably not even consider spacers if it would be the front we are talking about
lowenbrau
Explorer
ntsqd said:
Agreed. That is my application as well, to run wheels that are nearly 2" more backspaced (deep offset) than stock.
I simply haven't heard of any wheel space failures. Plenty of loose lugnuts but none where the properly tightened spacer has come apart. Frankly I can't imagine how a 1 or 2 inch thick piece of aluminum will come apart before the 1/4" steel or 3/8" aluminum wheel it is connected to does but I'm no engineer.
The rig in question will have a full floater but I'll eat my hat if anyone has seen a semi floater Land Cruiser axle flange break off its axle.
I think the subject should move to.. "How to ensure space lugs don't loosen" Locktite helps but I'd like to use castle nuts and lockwire. Any suggestions?
lowenbrau
Explorer
ntsqd said:
How does adding x inches of wheel spacer apply different forces than using a 2x wider rim with similar back spacing to stock? ntsqd's new FJ60 has identical forces applied to its semi floater with those nice wide aluminum wheels as it would with stock wheels and spacers? There is no question that both add stress but especially in the case of a rig overbuilt as the one in question, it is well within acceptable parameters.