Wheel hop at 45 mph

[rickycotte]

Ok Allen, I will find the cure and let you know. Although it might not fit your particular truck. BUT, since the symptoms and the treatment has been SO similar, I guess we are finally cornering the culprit.

I am trying to find in my mind if I ever changed these drums with aftermarket (cheapo) drums. I just have a small hint circling in my head.

It might be that I am having this vibration long ago and it has been noticed now because of increased use of my truck at highway speeds. I had this truck abandoned due to high fuel costs and a bad transmission.

Well, stay tuned. I will also look out for your stories.

 

[allenhillview]

We also changed the rearend in one of our trucks a few years ago, but... no bad change out just saved all drums and brake material, went back on new one, sure over time a lot of things wear but this is not something that one shouldn't be able to find and fix.

 

[rickycotte]

Guys! I finally nailed the problem!!! OUT OF BALANCE DRUMS!! Or I should say, really bad manufacturing QC.

Let me tell my story to guys who will definitively understand this relief.

I went today to my local Pep Boys joint and asked the service manager that I wanted to balance my truck's rear drums. You should have seen his face... SO, I then told him, never mind, just make a shop order for regular wheel balance.

After a brief wait, I then told the technician to take out the drums and to put them on the balancing machine spindle and to select STATIC mode. You should have seen his face also! "How am I going to fasten it to the wheel balancer?" he said. Don't worry, the brake drum hole id the same as the one on the wheel!!

Then he said: "How are we going to attach any weights to it?" Don't worry I have an idea, I said.

Well, all the technicians at the service bay were kind of skeptically looking at this crazy guy doing this experiment.

Ok, the procedure just went smoothly, he dialed in the drum width (4") and the separation with a special lever attached to the machine which lets it know how far away the rotating mass is. (This I am guessing but anyway, the machine nees this info/input).

When we rolled the first drum we got a whopping 12.5 oz of unbalance!! So, after cleaning the surface area of the drum with a wire brush, we attached 4 ea. 3 oz. lead weight strips distributed between the outer edge and inner edge. Thes are the kind they use for mag wheels. I have attached a photo.

You may know that by now I was getting excited. The technician also was surprised. Then, after attaching 12 oz. at the first location we ran the machine again. This time she asked for .75 oz on another location. This is good.

We installed .75 oz and ran her again. The result was a balance drum indicating 0.00 weight needed.

Then, we mounted the other side drum. Spinned her again and...BANG!! 18.0 ounces off!!! Now everybody at the service bay was paying attention.

We installed 6 ea. 3 oz. weight strips after cleaning up the area with wire brush. Around went the machine spindle again and stopped asking for 0.5 oz. on another angular location. Nice. One last go around and we got a 0.00 reading.

Mounted everything back on the truck and took it for road test. Unbelievable...total bliss... I do not have the words to describe the satisfaction of finally getting rid of an elusive problem.

My lesson: Even if I ever buy a new set of drums, I will ask them to be checked for balance; right out of the box, before installing them on my truck.

I may have to improve the weight attachment to the drum since I do not trust these lead strips using adhesive for fitting. I am almost certain that they will eventually fall out due to corrosion under the first lead strip which is holding all the other ones on top of it. So, I have to get creative and eventually improve this. But I already know were the monster is.

This may not be the case for othe SS fellow members with wheel hop. But I have shared my story as an example of what can go wrong and how elusive it can be. These drums are about 11 inches diameter and fairly heavy. I realize now what has been to have 30 ounces of hidden unbalance banging away on my rear axle. Now I have new tires, new wheels, new shocks...well, peace does not come easy or free all the time.

Good luck with your testing.

 

[allenhillview]

Well, Well, Well,
Thank you much. Can't wait to try this on cucv 1008 Drums I've called on some centric balance people but feel we can be creative at finding a way to attach that weight. Allen

 

[rickycotte]

Allen,

I am pretty sure you will be surpised as I was. Anyways, apart from the hassle, checking/balancing my drums came out free as Pep Boys will re-balance your tire/wheels practically forever if you bought them there.

Funny thing, actually the cure for the cause was the cheapest of them all!! Free.

4 New 235-85R-16 Tires: $793.00 4 New/used wheels at junkyard: $225.00
2 New 285-75R-16 tires before the 235's to check if this was the problem: $176.00(they were adjusted for wear) Drum Balance: Free...just my time

Getting rid of the hop/vbration and peace inside my cab: PRICELESS!!!

Yes, I have to find a better way to attach those weights. It might just be a matter of removing them and cleaning the drum surface real good with power wire brush and use one of these super epoxy adhesives. I would not want to weld anything on the drums as this would probably warp them and add unknown additional weight.

I just hope you find your cure for the malicious, persistent and fricking wheel hop on your rig.

Please share your stories with all of us.

 

[allenhillview]

We are on it. This morning we discussed how to attach weight, as ours' the race is part of drum, we have a decent shop here. Father in law has vast knowledge of machining. We have a lathe, bridgeport end mil in our inventory, we will try to machine piece to fit our hubs that will fit balance equipment.
Thanks so much, Allen

 

[rickycotte]

Right On!! You are well equipped sir. BTW, I will be visiting a friend in Cleveland, TN next week. Just for curiosity, how far away are you from there?

 

[engineman2]

Wow

Wow, surprised to see that they were that out of balance. It doesn't surprise me that a 50 lbs hub out of balance would do that, I'm just amazed at how much. So maybe that is the cause of my hopping too...time to investigate this further. Glad you got it all worked out though and this thread is helpful to those of us who have the same issue.

 

[Sharecropper]

Another way to balance the whole wheel assembly, including hubs, wheels, tires, lug nuts, valve stems, tubes and boots, is to install Balance Masters behind each wheel. This is what the 18-wheelers use on over-the-road trucks.

When I decided to run 11.00/20NDT on my M1028, I knew I was going to have a major balancing issue to overcome. Although my 20" custom wheels were produced by a machine shop, the inherent variables of the factory Firestone split rims mated to custom-machined centers, in conjunction with the large mass of the 44" tall NDT tires, tubes and boots meant that acceptable wheel balancing was going to be difficult to say the least.

So then I decided to look at Balance Masters' website, and discovered that they offer a model to fit a Hummer! I knew the Hummer bolt pattern was the same as my M1028, so I figured I would try a set. Although somewhat expensive, I bit the bullet and placed my order.

These things consist of a thin round steel plate with a tube permanently welded around the perimeter. Inside this tube is another continuous tube containing 40 ounces of Mercury. The way it works, as the wheel begins to rotate, the Mercury moves around the tube to find the position of least movement, thereby automatically balancing the entire wheel assemby. This process begins around 10-15 MPH and continues to adjust itself as needed. If the tire pickes up a rock, it adjusts itself. If the wheel gets mud or snow clogged in it, it again automatically adjusts itself. No need for weights ever again. If the rear hub is out of balance 18 ounces, the Balance Masters will automatically adjust for it.

Balance Masters: Hummers Product

These are pricey. I paid approximately $500 for a set of 4. But the way I see it, I will never have to pay for balancing another wheel on my truck for the rest of my life. How much is that worth in time and cash? An added bonus - I can move them from one truck to another, as long as the bolt pattern is the same.

These things are smooth. My truck rides smoother than my wife's Honda. There are no weights on any of my wheels and at 55 MPH there is no vibration whatsoever.

If you can afford the Balance Masters, it is definitely the way to go.

Hope this helps.

Mike Gresham

 

[allenhillview]

Mike, Talked to him this morning at balance master, our 1008 wheel will hit the ring because of those rivets on inside are at 12-1/2".

The OD on balance masters product is 12.625

He will not custom me, I'm all stock 235-85 -16, I'm going to try centramatic in Texas.

 

[allenhillview]

Right On!! You are well equipped sir. BTW, I will be visiting a friend in Cleveland, TN next week. Just for curiosity, how far away are you from there?

145miles straight due east , Love to have company. 423 913 1775

 

[Sharecropper]

Well I never even considered that a stock wheel would hit the tube. Good catch, my bad.

Would it be possible to use thin spacers on the lug bolts to clear the head of the rivets?

 

[Anubis8472]

That is odd...

Factory drums should come ballanced with weights tack welded on them....

Are there no factory weights on your drums?

 

[rickycotte]

That is odd...

Factory drums should come ballanced with weights tack welded on them....

Are there no factory weights on your drums?

That is what I have seen too. But the drums in my truck do not show even a trace that they had a counterweight somewhere, anytime. I am convinced now that these must be aftermarket. I have this truck since new and I do not recall the vibration when it took off fron the Chrysler dealer. It is odd but it could be even worse since it shows no regard for quality.

You should have seen them on the balancing machine going up and down. You could see it with the naked eye.

BTW, my weights have already went south...I knew it but, as I said to the technician, this is a test. I only need them to last until I feel the difference 2 or 3 kilometers down the road.

I suffered today a 90 miles plus trip with the thing again. Tomorrow I will try fastening them with a stronger adhesive and securing them with a stainless steel band. This should take take care of the centrifugal force flinging them away until I devise something better OR if I decide to go with the balancing discs mentioned above by Sharecropper. It is pricey but as he said, it is done forever.

Allen, I will look it up on Google Maps and who knows, maybe I might be able to put it in the route. Thanks!

 

[allenhillview]

Well I never even considered that a stock wheel would hit the tube. Good catch, my bad.

Would it be possible to use thin spacers on the lug bolts to clear the head of the rivets?

Yes it will be possible, what happens is I'll have to re-size lug length by 3/8" , spacers are there at centriimatic, then get balancers from balance master.

We may try balancing ourselves, if we achieve 75% of its affect on wheel hop then I think we can't feel it. Now its all very faint but that one 47mph gets me. 75% will get it out.

 

[allenhillview]

That is odd...

Factory drums should come ballanced with weights tack welded on them....

Are there no factory weights on your drums?

No weights, disassembled tonight for make ready on weights, also doing brakes, wheel cylinders, some hardware on backing plates. I did notice today that there is two places where metal has been removed at a factory level (machined out along inner edge as a balance method so it is possible they (budd) knew how much they could be out. But just on one not both drums.

 

[Sharecropper]

Allenhill - After thinking about it more, I believe there is enough flex in the Balance Masters center plate to compensate for the rivet head thickness. I truly believe if you installed the Balance Masters with the tube turned inwards and then torqued your lug nuts to specified torque, the plate would conform. I do know one thing - Balance Masters will balance the entire wheel assembly automatically and continuously forever under changing circumstances. Now that I have them, I will never again rely on machine balancing.

 

[allenhillview]

Mike, He says it shouldn't touch!; any mud, snow wouldn't be good trying to get out, plus friction would eventually get it, what is gauge on that metal (device)?

I just think thats bad for business to allow it to touch.

 

[rickycotte]

I sent them a message to see if they carry a model for Dodge 2500. They seem to have a very limited number of options at this time.

If they wish, I guess they could have a bigger business going on. I do not like the idea of having beads rolling inside my tires.

 

[Sharecropper]

Well heck guys, I was hoping that the Balance Masters would solve your issues like they did for me. I know I love 'em.