Rock between duals

[garybo]

We parked overnight by a high school with no prior clue that this rock was between our duals until the next morning. When we started driving the rotational 'thump thump' was very obvious. It moved a little with a small hammer and took a sledge to get it out without much difficulty. If it had been really stuck I would have jacked up that corner and perhaps deflated one tire to get it out. No harm done in this case. I don't know enough to recommend changing to single rear wheels, just thought this rock points out the importance of checking the tires before driving. If we had been on a noisy gravel road, we wouldn't have heard the 'thump'. Gary

 

[doug720]

A common problem and one I have experienced many times also. To remove the rock, I use a bar and lever it out from between the tires.

Doug

 

[LukeH]

In the first week I had my camper I got a brick caught between the twin rears. Like a naïve newbe I thought it would fly out on the motorway at 100km/h.
Two hours later I was changing a wheel because the brick had worn its way through one of the XZYs; the other was pretty far gone. I learnt my lesson the hard way.
Weirdly in 30000km of African roads I only had to hammer a stone out twice. So it's possible to get away with twins as long as you don't have to air down.

 

[Mc Taco]

Like a naïve newbe I thought it would fly out on the motorway at 100km/h.

:Wow1: Wouldn't want to behind or next to you when that happened!

 

[mog]

You can always add a removalable 'rock-pick' between the duals for use on rocky trails. That way the rock gets knocked out prior to a complete revolution and does not get pressed in by the full weight of your truck.

 

[Scrapdaddy]

Mog,

I never heard of a rock pick. Do you have picture of one or explain it alittle more. Sounds like a good idea, to me.

Thanks, Ron

 

[LukeH]

a flat bar on a spring that sticks in between the tyres. Usually the wheel end goes in below the wheel flasks and rubs metal to metal. The outer end is held on a little arm not dissimilar to the stabilisar bar holders.
Removable because I wouldn't like to have it rubbing at highway speeds.

 

[garybo]

Did a search and couldn't find "tire rock pick". Do you have an official name or place to buy one?

 

[doug720]

I think what LukeH is talking about is homemade, at last the ones I have seen are. You take a piece of 1/4 X 2" X 24" flat steel on edge, you drill a hole and weld a 8" or so inch long piece of 3/4 - 1" round steel tube or rod. The rod hole is about 8-10" from the end of the flat stock and centered in it.

To use, you place the flat stock between the dual tires and under the rock. Then push down until the rod contacts the tires and continue the downward pressure until the rock is levered out from between the tires.

Doug

 

[azken]

Carry a piece of chain about 4 or 5' in length...loop the chain around the rock (between the dualie) then fasten the ends of the chain above to the frame...drive forward or backward a few inches and the rock will come out...I used to have to do this when I had my belly dump...works like a charm with so sweat or nasty words

 

[TinysMav]

Bad problem for road-trains!

Used to have this problem all the time when operating side-tipper road-trains here in Australia. You'd tip your load out and run over the product, and a rock just the right size would wedge nicely between the duals on the trailer.

Smaller rocks could be worked out with a crow-bar or something similar, bigger rocks needed a length of drag chain wrapped around them and then fed under the following set of wheels. The following set of wheels would run along the chain, effectively holding it in place and pulling the rock out.

Never, ever run up the highway with rocks jammed between the duals - that would have to be the most irresponsible thing I've ever heard! People have been seriously injured, and cars written off, but being hit by a 10kg rock flying out from between a set of duals! I've personally seen a rock fly over 200m being flicked out at 100km/h - a car driver 20m behind the truck would have been killed "stone" dead...

 

[LukeH]

Like I said, I was naive. I've also seen rocks picked up and thrown by twins since and it is quite spectacular.

 

[highdesertranger]

i hate it when that happens. highdesertranger

 

[Scotty m]

http://www.vancouversun.com/travel/...+truck+tire+near+Cranbrook/7363084/story.html

It happened not too long ago in British Columbia.

 

[Jay H]

Used to have this problem all the time when operating side-tipper road-trains here in Australia. You'd tip your load out and run over the product, and a rock just the right size would wedge nicely between the duals on the trailer.

Smaller rocks could be worked out with a crow-bar or something similar, bigger rocks needed a length of drag chain wrapped around them and then fed under the following set of wheels. The following set of wheels would run along the chain, effectively holding it in place and pulling the rock out.

Never, ever run up the highway with rocks jammed between the duals - that would have to be the most irresponsible thing I've ever heard! People have been seriously injured, and cars written off, but being hit by a 10kg rock flying out from between a set of duals! I've personally seen a rock fly over 200m being flicked out at 100km/h - a car driver 20m behind the truck would have been killed "stone" dead...

That was good advice and exactly the solution that wildland firefighters use.