An education in wheel balance (long)...

[Bruce B]

I like to believe that I am pretty knowledgable on some subjects. Certainly when it comes to bolting wheels onto vehicles of any kind I have a lot of experience.... (I have made my living as a mechanic and now the owner of a shop that specializes in European auto repair). Anyway I have bolted on a lot of wheels in my day.

Some of you may have read my thread on the Marathon tires I have been carefully monitoring the tires for flaws from the moment they were new. Recently I discovered what I believe is a failing tire and have decided to replace the tires with Michelins.

In my quest to further isolate myself from tire woes I also decided to install a Dill pressure/temperature monitor system.

Another thing I investigated was reported lack of balance of the Dexter drums.
Andy at Inland RV has mention this before and I was skeptical, I had to see for myself....
Holy cow!!! These things are gross! I took the step of balancing my drums so that my wheels can now be balanced off the rig. This will be the subject of another post!

My final modification was to retrofit shocks to my Airstream as I really want to cover the bases here.

I began by mounting my new tires on the rims Airstream supplied with the trailer new, Sendel S20T's. I like the look and wanted to keep this wheel.

Now all that is left is to balance and check RoadForce numbers to verify that there are no problems. Here is the moment things begin to unravel!

A fussy balance takes about 5 minutes to set up. A RoadForce adjustment can take 15 or so minutes as a dismount is required but with quality tires this is seldom necessary. As part of a fussy balance one of the things a mechanic does is to verify that the rim is centered on the balancer. A procedure is run and once verified the balance can be made.

On the wheel that had the good Marathon (right side of the trailer) I could not pass the centering check. No matter what combination of lug-centric set up I used, no matter what I tried. The result was that the balancer began "chasing weight" (more about this later). I became annoyed and spent hours trying to get a perfect looking wheel/new tire to balance. I could not! Finally I simply took the wheel and tire to a tire shop explained my problem and asked them to show me what I was doing wrong. They could not get good results either. Critical inspection finally revealed that the tapers in the lug holes did not appear to be centered. Almost like they were not machined correctly or perhaps they were run loose??? The lugs have always been tight when I dismounted the wheels. I simply do not know what happened. (The Hunter Equipment representative is going to stop by Tuesday to see what he can determine, stay posted). Anyway that wheel is no longer something I trust.

Chasing weight is a condition were a wheel is balanced and a check spin is performed to verify that the balance is fine. After passing the check spin (balancer calls for no more weight or says “OK”), the “balanced wheel/tire” is removed from the machine and then re mounted on the machine for another check. A balanced assembly is balanced, it needs no weight but upon checking the second time the balancer calls for weight to be added. Obviously something is wrong with the balancer or the procedure.

Full of self doubt I recheck the Marathons by remounting them on a known good truck wheel to see if the decision to abandon them was valid. It was! Apparently the out of round lug pattern did not impact the RoadForce measurements very much. When I say out of round I mean by thousandths of an inch, just enough to prevent the wheel from bolting to the hub or balancer the same way every time.

Now to look at wheels. I really do like the look of the Sendel wheel but now I am beginning to wonder exactly what happened. In my search the first thing I discovered is that Sendel no longer has a listed telephone number. They also have not answered my email for information about their wheel. Are they still in business?

I then found a very interesting website of a trailer wheel manufacturer, HiSpec.
HiSpec Wheel & Tire, Inc. - The Safety Wheel
There is some very interesting reading here! In the end I purchased their Type 3 wheels that have the same appearance of the Sendels.

Lessons?

1.Balancing a tire on an Airstream separately is useless if you do not first balance the drum or alternatively balance the wheel on the drum.
2.Dismount the wheel/tire from the balancer and remount for a balance check, you may be surprised!
3. Wheel torque is important, re-torque is more important!
Look carefully at those wheels and inspect the lug bores for signs of loose running.
4.I really am impressed by the information on the HiSpec website. I called and easily got through to an engineer who verified my concerns about my current wheels and promised their wheels would be better in this regard (all without bashing the competition)
5. I knew less than I thought....

Bruce

[jcanavera]

I would assume that the wheels are still under warranty from Airsteam. While I don't feel qualified to comment on the technicalities of what you found, could this be an issue that you could bring up will a call to Jackson Center?

Here's a link to a site that claims that have Sendel's mailing address and local phone number. If this doesn't work maybe you could check with a distributor of their wheels and see what info they have on contacting them.

SENDEL WHEEL CORP. - Compton, California, United States

Jack

[Bruce B]

Originally Posted by jcanavera

I would assume that the wheels are still under warranty from Airsteam. While I don't feel qualified to comment on the technicalities of what you found, could this be an issue that you could bring up will a call to Jackson Center?

Here's a link to a site that claims that have Sendel's mailing address and local phone number. If this doesn't work maybe you could check with a distributor of their wheels and see what info they have on contacting them.

SENDEL WHEEL CORP. - Compton, California, United States

Jack

I tried that number, disconnected!

I suppose Airstream might listen to my story but there are a pile of variables in this equation. For all I know the lug tapers were fine originally. I never actually re-torqued. I did check for tightness a couple of times (not the same thing).
By the way, Dexter Axel says, "re-torque, re-torque and re-torque".

It really does look as the wheel was machined incorrectly to me but at this point it is water under the bridge. The replacement wheels were $79.00 each. Not too stiff if they are as good as I hope...

Bruce

[r carl]

If you are working with wheels and tires made in china you will likely have problems.

[Bruce B]

Originally Posted by r carl

If you are working with wheels and tires made in china you will likely have problems.

Not easy to find alternatives though. Even on new cars...
Bruce

[GCinSC2]

Bruce,

I think you've hit on several interesting points.

Roadforce balancer, these are actually locatable on their website in order to find a shop that owns one. They solve problems or identify them. Good stuff.

Repeat-ability. This is the hallmark of proper balancing. IF the results can't be repeated, something is wrong. If the mounting creates a new centerline each time then the results vary and vary. Chasing your balance. We have a balancer at work for flywheels and this remount test is critical to accepting the tooling and workpiece are doing their respective jobs.

My rig has disc brakes and as such the config of the rotor is a lot different from a drum. The drum has a lot of mass at the OD compared to the rotor. I'm not saying the rotor is immune from as machined imbalance but the mass at the OD is less. When I was chasing my brake issues I tried to find a shop that had a bubble balancer, looks like they are hard to find. I did buy a home version but it was not sensitive enough for the weight of the rotor. With your background, I bet you can figure out how to balance your drums. Then with wheels that repeat due to correctly machined lug tapers this thing will roll and roll and you'll be able to put a wheel on at any location and roll on. The lug taper issue reminds me of the procedure that a gunsmith uses to recrown a barrel muzzle. Wonder if a lug pilot re-taper cutter exists?

Please keep the observations coming. Good luck.

Gary

[GCinSC2]

Bruce,

Any updates?

[Bruce B]

Originally Posted by GCinSC2

Bruce,

Any updates?

Sorry about the delay,

We have towed about 300 miles since the changes to the trailer.
I did a quick video of the ride inside the Bambi showing just how much smoother the ride is with the shocks, tires and hitch changes but we never did a high speed run for the simple reason that my wife says NO!

I will say that no screws have come un done. Given the ammount of imbalance I found in the drums (new drums too!) I am certain that the trailer is now much happier.
We will head to FL this winter and I will get a good idea of just how different things are...

I will report back then.
Bruce

[GCinSC2]

Bruce,

Did the Hunter rep offer any insight?

Any further info on Sendel?

Good you got noticeable improvement from your efforts.

Gary

[Wingeezer]

Bruce

I recently switched to 16" Michelins.

I contacted Sendel to find a source of wheels in Canada but got no response at all. In the end, I dealt with a local tire shop who found me a wheel of similar spec.

They dynamically balanced the wheels/Michelin tires for me (although questioned why i would want that done on a trailer!), but not the drums.

I have centramatics on the trailer - do you have any thought as tho whether they are adequate to compensate for possible imbalance of the drums?

I'm sure the centramatics would help, but I wonder if they have enough "free weight" in the oil filled circumferential tubes to compensate for the degree of imbalance that might exist in the drums.

Brian.

[Bruce B]

Originally Posted by GCinSC2

Bruce,

Did the Hunter rep offer any insight?

Any further info on Sendel?

Good you got noticeable improvement from your efforts.

Gary

The rep from Hunter showed me that in the end my difficulties were the result of an improperly manufactured wheel. It drove us both nuts!

The wheels I purchased are nicely made and show promise. They look exactly like the Sendel but have better finish and steel inserts were the lugs secure. They are very round!!!
I can't remember if I posted the name of the wheel company so here they are. HiSpec Wheel & Tire, Inc. - The Safety Wheel. Their website has some interesting reading...

I personally believe that Sendel is a made to price point product that I would no longer personally consider.

You can get HiSpec on the phone for instance.... and speak to an engineer/tech person. I found the experience enlightening.

In the end, I had balanced (repeatable too!) wheel/tire assemblies that I have faith are correct and safe.

Pretty amazing.
Bruce

[Bruce B]

Originally Posted by Wingeezer

Bruce

I recently switched to 16" Michelins.

I contacted Sendel to find a source of wheels in Canada but got no response at all. In the end, I dealt with a local tire shop who found me a wheel of similar spec.

They dynamically balanced the wheels/Michelin tires for me (although questioned why i would want that done on a trailer!), but not the drums.

I have centramatics on the trailer - do you have any thought as tho whether they are adequate to compensate for possible imbalance of the drums?

I'm sure the centramatics would help, but I wonder if they have enough "free weight" in the oil filled circumferential tubes to compensate for the degree of imbalance that might exist in the drums.

Brian.

Interesting about Sendel no longer answering the phone hmmm?

I have never seen a Centramatic in my life so I can't comment. I would guess that they will do fine at balancing the assembly.

Conceptually they make sense and I would absolutely add them to my trailer today if I had no ability to balance those drums....

The imbalance of those drums was big. Think of a towel stuck on the wrong side of the dryer...

I will pull the drums next year and see how they test after 10,000 miles of towing.

Bruce

[LeeJ]

Bruce
I have an 85 Soverign,25', do you have a reference or source for determining the proper torque that shout be applied to my original steel wheels?
I appreciate the information you have provided.
Lee

[Snaken49]

Originally Posted by Bruce B

I tried that number, disconnected!

I suppose Airstream might listen to my story but there are a pile of variables in this equation. For all I know the lug tapers were fine originally. I never actually re-torqued. I did check for tightness a couple of times (not the same thing).
By the way, Dexter Axel says, "re-torque, re-torque and re-torque".

It really does look as the wheel was machined incorrectly to me but at this point it is water under the bridge. The replacement wheels were $79.00 each. Not too stiff if they are as good as I hope...

Bruce

Bruce,

It looks like Sendel is now owned by Tireco Inc. Neither company offer a contact phone number. But they do have a link for an email request.

Company | Sendel Wheels


Tireco, Inc

If you check the Sendel site's warranty info you'll see that the warranty is offered by Tireco Inc.

At the end of the day Centramatics may be the best way to maintain the proper balance of the entire wheel assembly over the life of the tires. I have a friend who owns a 28' Classic with Sendels and Michlens equipped with Centramatics. He has several thousand miles and is very happy with the results.

All the best!

Snaken

[RickDavis]

Very interesting thread.
I have noticed the typical Dexter drum will quickly and consistently rotate to the heavy spot down condition. I have asked Dexter about balancing drums and they don't seem to think the drums are any big deal.
I don't agree, but I don't see much chance they will change their policy

[ROBERT CROSS]

Bruce,

Very good info here.
Kind'a glad I've kept my USA OEM Alcoa's. No problems with lug seats, cracking or corrosion. TGFSF.

Realized quite quickly when first getting the Classic that something had to be done about balancing the running gear.
Took the wheels/tires to work to road force and still had a vibration at cruising speed. Short ride in the AS was very enlightening.
Researched the Centramatic's and installed them second Season.
They have worked flawlessly since installation.

Any Sendel update?

Bob

[Action]

When I worked for a domestic auto manufacturer the quality difference between that manufacturers stock wheels and an aftermarket was extremely noticable. That was in the '80s. I would assume quality standards would have improved for every manufacturer whether aftermarket or not. And yet this thread seems to point out that at least one aftermarket wheel manufacturer may have some quailty issues.

In the world of aftermarket, typically looks and price usually get a front seat to function. This thread is a very good document to checking the function of something we see every day. Non-standard wheels on all kinds of vehicles. Thanks Bruce!

When making a switch in any running gear piece make sure it is up for doing the job. Most of the running gear pieces AS uses they do not produce rather they contract out for these assemblies. So quality at the point of manufacturing isn't in their direct control. As it is posted in this thread (and else where) drums are an item that may need to be addresessed on amy one's trailer as it seems there is no tolerance for balance on that item. (It isn't so critical on discs) If the drum is or isn't balanced it is a hit or miss thing because they are not balanced at manufacturing.

>>>>>>>>>>>>>Action

[GCinSC2]

Bruce,

Thanks for info, makes sense can't balance a moving target. Steel lug inserts, my truck doesn't have that AFAIK. Direct contact with the wheel supplier safety something, very good sign.

Thanks.

Gary