[ExtinctJeep]

As I was riding along today in my BMW noticing how big bicyles seem when this low to the ground when I also noticed chains hanging down from the axles on a schoolbus, then an ambulance, then a firetruck. What are these chains for?

Just curious,

Fritz

Jeep...need I say more?

 

[LEVE]

The chains are an earth ground to disipate any static electrial charge that builds up.

 

[220]

Not sure exactly sure what these chains looked like that you saw. There is a company that sells a traction chain setup that looks like a wheel with chains radiating out from it. These are used in the ice and snow and kinda spin under the tire- rotate around and come back to the front to go back to the front of the tire. Hard to explain exactly- but they try and sell these to a lot of fleet managers for emergency vehicles.

 

[ExtinctJeep]

Leve,

That makes sense, but why would these vehicles have them, but most others don't? What makes them need them more?

Fritz


Jeep...need I say more?

 

[220]

Now that you mentioned the ground function I know what you are talking about. Although, all the vehciles I've seen with these chains has had them hanging off the front and rear bumpers. The ones I've seen have been utility company trucks or rail road service trucks- the kind that have a seperate set of wheels that come down to allow them to ride the tracks. I've never seen a firetruck or school bus that had them.

 

[LEVE]

The vehicle does build up a charge when driving. Most time you'll see chains on larger tankers carrying petrol, LPG, LNG, Oil, and other flamibles. The chains were picked up by Public Safety vehicles in the '40's as an ounce of prevention of expolsions of large gas tanks on the vehicles... in short... it's a cheap preventative. Most of the other vehicles don't carry fuel tanks as large as a semi trailer, nor have critical electronics on-board as safety vehicles... so the charge disipation is negligable. Next time the day is dry, or little humitity in the air, and you slide out of your vehicle... watch out for that little spark between you an ground that you generate. In the case of some of the fuel carriers, that little spark can be dangerous.

Also, there's less carbon black in today's tires. The carbon black was used for coloring and was useful in charge disapation. The newer tires have more of an isulation propery... and the chain may be even more needed on these vehicles.

 

[649]

What I beleive he saw was what wheelerfreak mentioned. They are called automatic tire chains. There were questions about them that I missed on the ASE exams because they are illegal here in jersey and I have never seen them in person. But they do use them in a lot of other states.

 

[ExtinctJeep]

What Leve tells me sounds good. What I saw were short chains grouped together hanging from the axles of large public trucks. What is really weird is that not all of the trucks have them. I just saw a firetruck without the chains. Oh well....thanks.

Oh yeah, here's a crappy drawing of the chains!

fritz

Jeep...need I say more?

 

[Guest]

Ther are automatic chains. I have never crawled under anything to see exactly how they work, but I know that spin under the tires. They are a fairly new item. If you ever get behind one of those truck that has them running, I wouldn't get too close. I am sure that they are prone to flipping up rocks and chunks of road debris. It would be nice, to not have to get out to chain up, and I am pretty sure that they weigh less than a set of regular truck chains.

Cage Up, Wheels Down
Jeepfiend
All my Jeeps are in pieces!

 

[LEVE]

Automatic Chains? Wow, I'm behind the times! I've got to look into those... I'm just gettin' too darn old.

Are they anything like this?

 

[649]

Those are them.

 

[Mel85CJ]

Actually, they aren't that new - I know that when I was in college and on the Volunteer Fire Department back in 1990-1993, we looked into these as an alternative to putting tire chains on & off in the wintertime, the dept. was in West Virginia & we had a lot of bad hills & a decent amount of snow.

-Mel

http://www.in2jeeps.com

 

[LEVE]

Wow Mel, now I feel even older!

Graveside services will be announced shortly!

 

[649]

If his going to college in 90-93 makes you feel old I'll just keep my mouth shut.

 

[kerryp]

Actually Jimmy I do believe that Mel is short for Melanie /wwwthreads_images/icons/smile.gif

82 Scrambler/360/T5/D300/4" SUA/AMC20/Rear Discs/Somers Bros Axles/D30/3:73's/Lockrite Lockers.
2001 Bare Stock Trendy Jeep Sport (everyday driver)
Smithville, Texas
Member TX4X4 Cyber Club

 

[649]

Actualy you are right. Sorry about that. I guess they are right that when you assume something you do make an ass out of yourself.

 

[LEVE]

Mel, keep on talking...

everything makes me feel old.... a few years ago my then 12 year old came up to me and said: "Dad, you're graying as we speak." I knew from that minute on... it was all downhill.

 

[Mel85CJ]

Yup, thats me, Melanie.
By the time I graduated I was the Fire Lieutenant and an EMT. Got to drive a bunch of big fire trucks along with gearing up. Too busy now a days to commit to volunteering, out of town too much for work.

I'll be celebrating my 30th birthday down in New Mexico for the WNRCC - can't think of a better way to do it /wwwthreads_images/icons/smile.gif.

-Mel

http://www.in2jeeps.com

 

[kerryp]

Man Mel, now you made me feel old, I just turned 37 today, fortunately I still feel 18 and my wife says I act like a two year old sometimes, so I'm good to go /wwwthreads_images/icons/smile.gif

82 Scrambler/360/T5/D300/4" SUA/AMC20/Rear Discs/Somers Bros Axles/D30/3:73's/Lockrite Lockers.
2001 Bare Stock Trendy Jeep Sport (everyday driver)
Smithville, Texas
Member TX4X4 Cyber Club

 

[Guest]

Yeah, that's them LEVE...they aren't quite as efficient as real chains are. You can only switch them on at very low speeds. From what I hear, they're great to get started at a stoplight or something, where you're at a dead stop. But you can't have 'em on going down the highway, and you can't be driving along and switch them on if you hit a patch of ice and need to stop fast.

Moneyless, Will weld for jeep accessories.