Wheel Spacers vs. Backspacing

[Fergie]

Throughout the various boards, folks seem to be of the opinion that wheel spacers are a bad idea, and that proper backspacing is preferred.

Among the various reasons that are cited, the most prominent and often cited is the accelerated wear on wheel bearings caused by the spacers. The extra leverage created by moving the wheel farther out(longer tourque arm) causes the bearing to fail prematurely.

I got to thinking about all of this, and to me, the backspacing on a wheel creates the same, longer torque arm on the axle shaft as the wheel spacer does. Same result, different metod of getting there.

Can you all weigh in with your opinions, and actual experience on the topic, not just conjecture.

All in all, it won't matter as I will be installing my wheelspacers on my WJ next week, but figured I'd like to hear some other peoples ideas.

Thanks

Gavin

 

[Jeep]

I have owned a 4WD truck shop since 1994. I have always disliked wheel spacers for a number of reasons, the most dominant reason being safety. We have had several vehicles towed in (approx 12-15) with missing wheels due to wheel spacers. Nobody was personally injured in the above instances with the exception of the pocket book. Now here is the latest and it's a few years old now but a good friend of mine who is not financially restrained put a set of spacers on his brand new 2006 F-350 dually to prevent the tires from rubbing, I did not sell them to him based on my dislike for them, and recommended he change tires sizes or buy the proper wheels which we sell. He opted for the spacers, looked after them as far as manufacturers torque recommendations and retorquing instructions but that did not stop the loss of the right rear tire the destruction of the box and rear bumper or the damage to his $45 000 5th wheel trailer which in the end caused the insurance company to write the trailer off (the tire/wheel ended up inside the trailer). Now here is the worst part, the insurance adjuster noticed the wheel spacer, and denied coverage to the entire claim after an investigation turned up the fact that the spacers carried no product liability insurance. So he got lucky and only lost approx $54 000 by the time the dust settled, I say lucky because his wheel didn't end up in the oncoming lane and indescriminately killing somebody. As far as I am concerned a million dollar wheel with a million dollar wheel spacer is worth less than a rusty ten dollar junkyard wheel of the correct size and offset. Why would you buy wheel spacers when you can buy a cheap Eagle 0589 series wheel in almost any size for around $100? If you cannot afford the wheels you definitely cannot afford the repairs that a cheap set of wheel spacers have the potential for. Let the safety considerations of the people who share the road with you be the deciding factor if you don't place that much value on yourself or your passengers. I post this with the ultimate regard for safety, I do not intend any insult, discrimination, disrespect, or hard feelings. I have been in the industry full time for 24 years and have enough first hand experience to provide the comment I did.

Regards,
Mark

Oh yeah....HAPPY NEW YEAR!

 

[Antichrist]

I got to thinking about all of this, and to me, the backspacing on a wheel creates the same, longer torque arm on the axle shaft as the wheel spacer does. Same result, different metod of getting there.

You're absolutely correct.
Though I suppose, technically there may be more with spacers because of the added weight of the spacer, but I'm betting for all intents and purposes, there's no difference.

Actual experience? I run spacers on my Disco, but Land Rover hub bearings are larger than the other typical 4WD bearings I've looked at, so it's not a fair comparison. In addition, there are a lot of other factors as well. Like mud, water, dirt, road salts, type of grease, hub nut torque, etc.

 

[Fergie]

I have owned a 4WD truck shop since 1994. I have always disliked wheel spacers for a number of reasons, the most dominant reason being safety. We have had several vehicles towed in (approx 12-15) with missing wheels due to wheel spacers. Nobody was personally injured in the above instances with the exception of the pocket book. Now here is the latest and it's a few years old now but a good friend of mine who is not financially restrained put a set of spacers on his brand new 2006 F-350 dually to prevent the tires from rubbing, I did not sell them to him based on my dislike for them, and recommended he change tires sizes or buy the proper wheels which we sell. He opted for the spacers, looked after them as far as manufacturers torque recommendations and retorquing instructions but that did not stop the loss of the right rear tire the destruction of the box and rear bumper or the damage to his $45 000 5th wheel trailer which in the end caused the insurance company to write the trailer off (the tire/wheel ended up inside the trailer). Now here is the worst part, the insurance adjuster noticed the wheel spacer, and denied coverage to the entire claim after an investigation turned up the fact that the spacers carried no product liability insurance. So he got lucky and only lost approx $54 000 by the time the dust settled, I say lucky because his wheel didn't end up in the oncoming lane and indescriminately killing somebody. As far as I am concerned a million dollar wheel with a million dollar wheel spacer is worth less than a rusty ten dollar junkyard wheel of the correct size and offset. Why would you buy wheel spacers when you can buy a cheap Eagle 0589 series wheel in almost any size for around $100? If you cannot afford the wheels you definitely cannot afford the repairs that a cheap set of wheel spacers have the potential for. Let the safety considerations of the people who share the road with you be the deciding factor if you don't place that much value on yourself or your passengers. I post this with the ultimate regard for safety, I do not intend any insult, discrimination, disrespect, or hard feelings. I have been in the industry full time for 24 years and have enough first hand experience to provide the comment I did.

Regards,
Mark

Oh yeah....HAPPY NEW YEAR!

How was the determination made that the spacer caused the loss of the wheel?

 

[JIMBO]

:archaeolo I'm glad you posted that, with your personel experience

I had your same feelings and DREAD, when I used the 2" adapters on my JEEP JK, and I removed them after 20 miles--bad, dangerous idea and MOST of the wheels made nowadays, have a wide variety of backspace's available, trouble is, most people will buy the "ONE's ON SALE" AND THEY DON'T HAVE A CHOICE IN BACKSPACE, SO THE CHANCES ARE TAKEN

IT'S A "clear and present danger", SHOULDN'T DO IT, NO MATTER WHAT THE VEHICLE !!!

CHEERS

:bike_rider: :safari-rig: :safari-rig: JIMBO

 

[2drx4]

You are correct in that the load applied to the bearings is the same regardless if you use a wheel with more BS or a spacer. Providing the actual end tire placement is the same.

There is two types of spacers... The ones that bolt on, and have a set of studs in them for retaining the wheel are alright, more on them... The ones that the existing studs go through completely and are used to hold the tire on are NOT acceptable (at least, IMHO), and I would NEVER run them.

I've run spacers before, the ones with a set of studs in them, but only on one axle to make up for slight differences in widths. If I was to buy rims to correct this, I'd need two different styles of rims on the truck. Which is not convenient, or really practical to me. Providing the spacers are actually made correctly (6061-T6 or 7075-T6 aluminum, or say some decent low carbon steel), the studs are installed correctly, and you do a retorque on the inner nuts, I have confidence you would NEVER have an issue with them. However, most spacers are not made of decent aluminum, have less than ideal machining, and rarely do people retorque the inner lugs. For my current truck, I will not be running spacers as I will have the axle widths matched correctly without them.

I would NOT recommend running spacers on both axles. It is just asking for a headache (or worse) in the long run. Decent rims can be bought for a similar price. And by decent, I mean better than a lot of OEM rims.

 

[Fergie]

:archaeolo I'm glad you posted that, with your personel experience

I had your same feelings and DREAD, when I used the 2" adapters on my JEEP JK, and I removed them after 20 miles--bad, dangerous idea and MOST of the wheels made nowadays, have a wide variety of backspace's available, trouble is, most people will buy the "ONE's ON SALE" AND THEY DON'T HAVE A CHOICE IN BACKSPACE, SO THE CHANCES ARE TAKEN

IT'S A "clear and present danger", SHOULDN'T DO IT, NO MATTER WHAT THE VEHICLE !!!

CHEERS

:bike_rider: :safari-rig: :safari-rig: JIMBO

Why though? Not being a smart MMM, seriously, why such bad feelings? Was this just a feeling, or is there more empirical data?

 

[JIMBO]

:archaeolo Well, logic plays an important part along with wheel bearing vertical/angle force dispursement

Except for "Dually" truck rear axles/brgs, most wheel (single) brgs are designed/stress insured and race supplied for vertical forces with horizontal torque forces compensated for (within ??distance of brg center), based on Axle diameter/wheel size/IFS or solid axle-etc:

when you apply "spacers" 1"/1 1/4"/1 1/2 " using the existing hub studs, you are over "torquing" the stud designed strength and just delaying, the lug loose stud, syndrome for a matter of time

When you use the (two part) adapter, you're generally talking about 2" away from the HUB "load bearing" face and not only have at least twice the No. of lug nuts, that require constant TORQUE CHKS, BUT the bearing load has been moved out (*depending on backspace) up to 4 or 5 inches away from the vertical load parameters of the axle bearings

Insurance agents, will check on these situations, as often as they will when there is a wreck involving an off-road vehicle, that has the SWAY BARS DISCONNECTED !!

There ain't no free lunches anymore

:gunt: :safari-rig: :safari-rig: JIMBO

 

[Taz]

I have been running spacers for 3 years and 60,000 miles with out problems. I check them often and retorque them. I wanted that wider stance and yes I have good back spacing on my wheels as well. I feel strongly that most people who run them do not torque them properly and do not check them near enough. I run the ones with the studs and they have the center in them. I can't remember the name but they have been excellent and I won't take them off as the added stabilty on the TJ is amazing compared to not having them (1-1/4" on eack side). I have not had any bearing failures but I have also changed them out a couple of times due to changing axles. I am sure it is harder on the bearings thats a given, but anything I do adds extra stress to my vehicle, that is just the nature of what we do.

 

[Fergie]

:archaeolo Well, logic plays an important part along with wheel bearing vertical/angle force dispursement

Except for "Dually" truck rear axles/brgs, most wheel (single) brgs are designed/stress insured and race supplied for vertical forces with horizontal torque forces compensated for (within ??distance of brg center), based on Axle diameter/wheel size/IFS or solid axle-etc:

Makes sense.

when you apply "spacers" 1"/1 1/4"/1 1/2 " using the existing hub studs, you are over "torquing" the stud designed strength and just delaying, the lug loose stud, syndrome for a matter of time

Rotational torque, or the torque arm mentioned earlier? Rotational, no, you torque the nuts the same as the factory spec. Torque arm, the additional weight of the spacer is negligible compared to the extra weight of a larger tire. Same goes for the physical material strength of the stud. The weight and extra forces incurred by the spacer are small.

When you use the (two part) adapter, you're generally talking about 2" away from the HUB "load bearing" face and not only have at least twice the No. of lug nuts, that require constant TORQUE CHKS, BUT the bearing load has been moved out (*depending on backspace) up to 4 or 5 inches away from the vertical load parameters of the axle bearings

How is the distance created by the spacers different from the distance created by different backspacing? Aside from the weight of the spacer, the positioning of the weight is similar, in reference to the tire/wheel combo. When you consider the weight of a 33" MT compared to the stock tires on a vehicle, and the parameters of bearing loads, the spacer weight is of minor concern.

Insurance agents, will check on these situations, as often as they will when there is a wreck involving an off-road vehicle, that has the SWAY BARS DISCONNECTED !!

There ain't no free lunches anymore

:gunt: :safari-rig: :safari-rig: JIMBO

An insurance agent may also look for a lift kit, different shock absorbers, different gearing(or T.A.D.s) or even differnt tires.

 

[2drx4]

:archaeolo Well, logic plays an important part along with wheel bearing vertical/angle force dispursement

Except for "Dually" truck rear axles/brgs, most wheel (single) brgs are designed/stress insured and race supplied for vertical forces with horizontal torque forces compensated for (within ??distance of brg center), based on Axle diameter/wheel size/IFS or solid axle-etc:

when you apply "spacers" 1"/1 1/4"/1 1/2 " using the existing hub studs, you are over "torquing" the stud designed strength and just delaying, the lug loose stud, syndrome for a matter of time

When you use the (two part) adapter, you're generally talking about 2" away from the HUB "load bearing" face and not only have at least twice the No. of lug nuts, that require constant TORQUE CHKS, BUT the bearing load has been moved out (*depending on backspace) up to 4 or 5 inches away from the vertical load parameters of the axle bearings

Insurance agents, will check on these situations, as often as they will when there is a wreck involving an off-road vehicle, that has the SWAY BARS DISCONNECTED !!

There ain't no free lunches anymore

:gunt: :safari-rig: :safari-rig: JIMBO

You can get a spacer that has studs pressed into it that is only 1" thick. I have a set of them in 6x5.5. Likewise, you could get them in a 3" version if you wanted. Yes, common sense must prevail in this case. But it is the same as if I decided to go from some factory 6.5" backspacing rims to say a 3.5" backspacing rim, or if I just used a 3" spacer. Given the design of many hubs, that is probably a really stupid idea. With others, it really won't matter as much. This will come down entirely to the praticulars of the vehicle in question. Full-float applications in general will have a lot less issues as the two wheel bearings are farther apart. Semi-float applications (such as a rear D44) will have more trouble as they only have one wheel bearing per side, and the axleshaft itself must support a great deal of loading (which in turn is transferred to the carrier and its bearings). This loading will increase as you move the tire out, asking for more issues... Unitized hubs may or may not care - F450 or Dodge 1-ton stuff is massive enough that it makes up for a lot. Also, lots of wheel bearings can effectively 'fail' but not result in the loss of a tire or all control of the vehicle.

 

[Jeep]

In the case of the wheel loss the spacer was still holding the inner wheel on, it was the outer wheel that came off and raised hell with everything. The spacer was aluminum and although almost destroyed it was still holding the inner wheel on. Regardless of how the insurance company disqualified the claim I wouldn't want to be involved in a 5 year legal action that I stand a good chance of losing and incurring even more loss. And as stated, what if that wheel would have killed someone?

 

[HenryJ]

Front 1.25" and rear 3" wheel adapters on my truck 70K miles and no worries here.
They are as strong or stronger than the wheels I run.
Wider track and matching the track width F/R , without differently rear spaced wheels was my reasoning.

 

[michaelgroves]

Seems to me that there is only one functional difference between using properly studded spacers and backspaced wheels, and that's whether the spacer is more likely to result in a wheel coming off.

Additional strain on wheel-bearings has been mentioned quite a bit and applies equally to both. (With some red herrings about the weight of the spacers versus the weight of bigger wheels - neither of which are the real problem. It's the weight of the vehicle which is being supported incorrectly by the bearings).

The other issue is that of steering. The steering king-pin is the the pivot point, and with standard wheels is usually tucked deeply into the dish of the wheel, just in-board of the brake drum/disc. So when you steer, the wheel pivots around the centre-line of the tyre (or thereabouts).

With a heavily spaced or backspaced wheel, the whole wheel moves backwards and forwards in an arc within the wheel arch. (Imagine an exaggerated spacer, say a metre thick, and picture the way the wheel - way out to the side of the truck - would pivot around the king-pin).

This leverage in the horizontal plane is more of a problem than the wheel bearings, although it only applies to the front wheels. It makes for interesting handling, a lot of bump-steer, and stress on the steering components. The greater the spacing, the greater the problem. As with the wheel-bearing problem, the steering problem also applies equally to spacers and back-spaced wheels.

As regards the possibility of losing a wheel, I can see why a spacer would increase that risk - more nuts means more possibility of mistakes, even if the spacer is well designed. But one could always make them integral with the hub, though, surely? (A bit of weld over the threads?) Personally, I'd just use some good thread locking fluid, and treat them as part of the hub. I can't agree with Jimbo that all spacers are dangerous per se, no matter how many capital letters are used!

However, if a wheel does come off, and you're using spacers, I think the reality is that you can expect the insurance company to balk, especially if it's the spacer that has come off the hub, or failed in some way, even if it's a fluke. So from a practical point of view you might be better off with backspaced wheels, no matter how illogical that may seem. At the very least inform the insurance company of the changes, preferably along with a list of other (more) sensible modifications.

 

[JIMBO]

:archaeolo Touche-Michael, of course NOTHING is 100% certain

Seems to me that there is only one functional difference between using properly studded spacers and backspaced wheels, and that's whether the spacer is more likely to result in a wheel coming off.

Additional strain on wheel-bearings has been mentioned quite a bit and applies equally to both. (With some red herrings about the weight of the spacers versus the weight of bigger wheels - neither of which are the real problem. It's the weight of the vehicle which is being supported incorrectly by the bearings).

The other issue is that of steering. The steering king-pin is the the pivot point, and with standard wheels is usually tucked deeply into the dish of the wheel, just in-board of the brake drum/disc. So when you steer, the wheel pivots around the centre-line of the tyre (or thereabouts).

With a heavily spaced or backspaced wheel, the whole wheel moves backwards and forwards in an arc within the wheel arch. (Imagine an exaggerated spacer, say a metre thick, and picture the way the wheel - way out to the side of the truck - would pivot around the king-pin).

This leverage in the horizontal plane is more of a problem than the wheel bearings, although it only applies to the front wheels. It makes for interesting handling, a lot of bump-steer, and stress on the steering components. The greater the spacing, the greater the problem. As with the wheel-bearing problem, the steering problem also applies equally to spacers and back-spaced wheels.

As regards the possibility of losing a wheel, I can see why a spacer would increase that risk - more nuts means more possibility of mistakes, even if the spacer is well designed. But one could always make them integral with the hub, though, surely? (A bit of weld over the threads?) Personally, I'd just use some good thread locking fluid, and treat them as part of the hub. I can't agree with Jimbo that all spacers are dangerous per se, no matter how many capital letters are used!

However, if a wheel does come off, and you're using spacers, I think the reality is that you can expect the insurance company to balk, especially if it's the spacer that has come off the hub, or failed in some way, even if it's a fluke. So from a practical point of view you might be better off with backspaced wheels, no matter how illogical that may seem. At the very least inform the insurance company of the changes, preferably along with a list of other (more) sensible modifications.

I just tend to stay on the OVERSAFE recommendations, If I drived alone, it doesn't matter, but I always have family with me and I won't let a mechanical accident occur, because I knew about it and DID NOTHING

Thanx for your ref to the King-pin stress, adapters/spacers affect EVERYTHING, they use them for RACING all the time--but this ain't racing

If the wheel mfg doesn't offer the proper backspace option---go somewhere else--Coulda-Woulda-Shoulda

:bowdown: :088: :safari-rig: JIMBO