SUBJECT: Re: snow chain - front or rear
ORGANIZATION: University_of New Hampshire
In article <3519e3a6.594202788@news-pnh.mv.net>, Peter D. Hipson wrote:
I would like to get some advice on whether to install snow chain on the 2ront or rear wheels of a 97 Pathfinder 4x4? Of course if I install them on the front wheels, then I should be in 4WD mode. I've asked Nissan and they strongly advice on only installing on the rear wheels.
Any comments?
Sounds like you answered your own question: "Nissan and they strongly advice on only installing on the rear wheels"!
Why do you want them on the front wheels? (I assume you are looking for someone to counter Nissan's comment) Probably there are clearence problems with the front, so be very careful if you try it. Check to make sure you don't destroy the stearing, and other components, or that the chains don't get broken, and then trash your wheel wells.
Excepting for certain conditions, and places, good driving practices are much more important than tire chains! Rather than chains, I'd suggest a more agressive tire might be the best solution for your problem
Want to know the reason to put them on the rear only if you've got
only 1 pair? Going downhill.
You're out on a nice snowy trail, and you put your only pair of chains on the front wheels, since the chains multiply traction like you wouldn't believe. You figure it's sort of like the front wheel drive theory, you'll have the best traction on the turning wheels to pull you through corners. You are right, and you laugh haughtily as you watch your rear chained friends take corners wide, miss corners, and generally not have a lot of directional control. Then you come to a big hill you have to go down. Your rear chained friends go down no problem, except a few missed a turn in the middle and had to get winched back on track. Now your gonna show 'em how it's done, figuring your front drive chains will pull you through the corner. You start down, and notice the hill is a little off camber. Then you notice your back end is swinging out, and catching up to the front quite quickly. You now find you are going down the track almost sideways, and finally enough snow gets piled up next to your sideways sliding tires to tip the jeep over. On your side, you take off sliding down the hill on your sheetmetal, plowing into your friends who are standing in awe in front of their trucks at 30+, killing all of them except one, who was off taking a leak. But before it fully sinks in that you have to find new drinking buddies, you pile into the side of a pickup with those dreaded side tanks and blow up in a firery conflagration. If there is such a word. Anyway, what happened?
Well, you forgot that your rear tires weren't passively following, like on a true front wheel drive, they were spinning. Spinning without much traction. This leads to sliding. Your front tires, with the chains, had great traction, and weren't going anywhere. The off camber nature of the trail (and if not that then the corner would have) caused gravity to push your sliding rear end down; you were an upside down pendulum, with the pivot being your front tires and not enough traction in back to keep your rear from coming around. If you could go perfectly straight down a perfectly even trail, with no off camber, your rear would have stayed balanced behind your front. If you find a trail like this, let me know. Your rear chained friends, had they lived, would have explained to you that their pivot was on the back, and so going down hill kept them in a stable position. Going uphill they are at a disadvantage, but they have the added control of being able to turn the front wheels and control to some degree the direction they are spinning, and therefore the sliding. But not a whole lot (in a chained rear wheel drive car the front tires aren't spinning, so altough still a bitch in snow up steep hills, not nearly so bad).
Anyway, upon returning from bleeding his lizard, your sole surviving friend surveyed the scene and did what any intellignet person would do: he took a pair of chains from one of his (now dead) friends rigs. With chains all around he was stable up and down hills, had chains pulling him around corners, and also generally enjoyed a whole lot more traction than he had before.
- Jeff
From: MTSOBCZAK@aol.com
Subject: Tire Chains Tips #21/MS (Long)
To: landcruisers@tlca.org
Prior post summaries on the use of chains I thought might be good to review - Stay Safe for the holidays!!!
Chains - All four chained is obviously best, however, if you are going to run just one pair, generally put them on the front for increased directional control. On a steep slippery hill, you definitely want the chains on the uphill end. Control is more important than traction. In the event the unchained end loses traction, you want it to be the lower end of the rig so that it doesn't try to pass you as it slides down the hill. The average speed should be well under 10 mph and usually 20 - 30 mile per hour on dry roads. For even better performance, try two chains on each tire with the cross chains offset. You could also double up the cross chains on a single unit. Chains that are as TIGHT as possible will get maximum life at 30 mph or less. 40 mph is about 57% chain life and 50 mph drops it to 31% chain life. If the chains are loosened by just one link, each side gives you 50% life at 30 mph 16% at 40 mph and 7% at 50 mpg. Do not deflate the tires to install the chains. After installing them, driving about 1/4" mile, stop and re-tighten the chains and never use them on "all
cable" type.
Regular tire chains (the kind that are shaped like ladders when they're spread out on the ground, with only two runners and a whole bunch of rungs) have little or no effect on lateral traction. There are certainly designs (such as "Diamond chains") which will keep more chain between your tire and the ground, but plain old ladder chains do provide lateral traction as well. If your tire is not turning, but is instead sliding, and the cross chains are spaced and located in such a way that none are on the ground, then it's true they can't help much. So long as the tire is rolling, and you have at least one cross chain in contact with the ground, the chains will help your directional control.
Anyway, if you're getting one set, you're probably best off to put them on the back, because they won't make your steering worse than it would be without them.
For almost all use, especially on road use, if you run only one set of chains on a four wheel drive rig, you should run them on the front. First of, because the chains WILL HELP your steering, not hinder it..Secondly most of you braking force is available at the front wheels, not the rear. At the low speeds that chain use is appropriate for, this is where you want the bite to slow down. And lastly, in low traction conditions, a chained rear end and an unchained front end will tend to allow the rear axle to push the front in a turn. This will result in under steer behavior. Sometimes extremely so. And it will not be constant, or predictable. About the only time you should put chains on the rear only of a Cruiser is for descending a steep slippery grade (mud, snow, ice or whatever). In this situation you want to have your traction ability weighted toward the rear. Otherwise you may find yourself in a situation where the tail end simply will not stop when you apply the brakes. The front end will, but and ruts or irregularities in the surface will allow the rear of the rig to slip to one side or the other. Once it does, it will continue sliding downhill and spin you right around. (Assuming that the slope is not steep enough to cause you to tip over when you get turned sideways to it.) When climbing a steep slippery slope you will of course get more traction advantage from the chains if they are mounted on the rear. However if the traction capabilities of the front tires are degraded enough by the snow, ice or mud, you may find the front end sliding back downward if you get crossed up at all. And if you don't make the climb, and have to back down, you are now in a similar situation to before, where you want to have the most grip with the uphill axle. An improvement I have seen done to ladder style chains is to purchase additional cross chains (normally sold for repair purposes), and double up the number of cross chains. This gives much more traction, both in the direction of wheel travel, and laterally as well.
Probably the biggest mistake that people make with chains is driving too fast. If conditions are slippery enough that you really need chains on your 4x4, then 30 mph is TOO FAST. I seldom travel over 15-20 when the rig is chained, whether on the road or the trail. Higher speeds will also wear your chains at a geometrerically faster rate. Mark Whatley
Ice driving - I drove in low range and had very good luck in using the low range in conjunction with compression braking, double clutch downshifting and some gentle squeezing of the brakes (threshold braking). I was able to stop in conditions where I was not able to in high range, two wheel drive mode.
From: Trey
To: landcruisers@tlca.org
Subject: Re: Tire Chains Tips #21/MS (Long)
MTSOBCZAK@aol.com wrote:
Prior post summaries on the use of chains I thought might be good to review - Stay Safe for the holidays!!!
For even better performance, try two chains on each tire with the cross chains offset.
Tire chains were not meant for this. If you can't get to where you need to go with one good pair (or all 4s chained), then you really don't need to be there. This is an unsafe idea.
You could also double up the cross chains on a single unit.
MUCH better idea. Have done this many times...
After installing them, driving about 1/4" mile, stop and re-tighten the chains and never use them on "all cable" type.
Never use "rubber adjusters" on "all cable" type.
Regular tire chains (the kind that are shaped like ladders when they're spread out on the ground, with only two runners and a whole bunch of rungs) have little or no effect on lateral traction. There are certainly designs (such as "Diamond chains") which will keep more chain between your tire and the ground, but plain old ladder chains do provide lateral traction as well.
No offense but you contradict yourself. Your first sentence say's ladder chains have "no effect on lateral traction" and the you say "plain old ladder chains do provide lateral traction as well".
If your tire is not turning, but is instead sliding, and the cross chains are spaced and located in such a way that none are on the ground, then it's true they can't help much.
You must have the wrong size chains for your tires then. A correct sized chain will have 2 cross chains touching the ground when spaced correctly.
Anyway, if you're getting one set, you're probably best off to put them on the back, because they won't make your steering worse than it would be without them.
This is sniped from you first sentence.....
"All four chained is obviously best, however, if you are going to run just one pair, generally put them on the front for increased directional control."
Then you say...
For almost all use, especially on road use, if you run only one set of chains on a four wheel drive rig, you should run them on the front.
Your confusing...
First of, because the chains WILL HELP your steering, not hinder it..Secondly most of you braking force is available at the front wheels, not the rear. At the low speeds that chain use is appropriate for, this is where you want the bite to slow down.
Off road it will help steering and traction. As for breaking force, if the front doesn't "grab" then your chained rear will.
And lastly, in low traction conditions, a chained rear end and an unchained front end will tend to allow the rear axle to push the front in a turn. This will result in under steer behavior. Sometimes extremely so. And it will not be constant, or predictable.
Slow down. We drive in snow and ice 5 + months a year :-)
About the only time you should put chains on the rear only of a Cruiser is for descending a steep slippery grade (mud, snow, ice or whatever).
Or daily driving on pavement.
When climbing a steep slippery slope you will of course get more traction advantage from the chains if they are mounted on the rear.
I disagree. I'd prefer the "pulling" tires to have the traction in this situation verses the "pushing" tires for the very reasons you state below.
However if the traction capabilities of the front tires are degraded enough by the snow, ice or mud, you may find the front end sliding back downward if you get crossed up at all. And if you don't make the climb, and have to back down, you are now in a similar situation to before, where you want to have the most grip with the uphill axle.
An improvement I have seen done to ladder style chains is to purchase additional cross chains (normally sold for repair purposes), and double up the number of cross chains. This gives much more traction, both in the direction of wheel travel, and laterally as well.
This is the best and safest way. Please do not double up tire chains (2 sets on 1 tire).
Probably the biggest mistake that people make with chains is driving too fast. If conditions are slippery enough that you really need chains on your 4x4 , then 30 mph is TOO FAST. I seldom travel over 15-20 when the rig is chained, whether on the road or the trail. Higher speeds will also wear your chains at a geometrerically faster rate. Mark Whatley
I couldn't have said it better myself :-)
FROM: "Jarhead"
SUBJECT: Re: Tire Chains
NEWSGROUPS: rec.autos.4x4
"David & Ann" wrote in message
news:3C63459A.69CD8A76@mediaone.net...
I've got a set of tire chains on the rear wheels of my '89 Toyota 4WD pickup so I can get up the snow and ice covered hill in my back property.
The question is, can I put another set of chains on the front wheels? I've had a couple of people tell me that you should never put tire chains on the front wheels. Is that only because of wheel well clearance issues or is there some other reason? I've got 35" mud tires and 7" of lift so there are no clearance issues on my truck.
Also, has anybody had any problems running tire chains with a Detroit Locker? When I make tight turns in my driveway, I can hear the inside wheel skipping over the chains and I'm worried I might break an axle or something.
Thanks.
- David
30 years ago when I taught school on the Jicarilla Apache Reservation, one of the El Paso Natural Gas guys clued me in on how they ran in the Oil bearing Shale gumbo in that area.(Grey dirt that turned into Axle grease after a rain).
First of all they ran tall,narrow tires and when needed they ran front chains ONLY. Also, they added extra heavy cross chains between the regular cross chains and left them loose so that the chains would clean themselves as they rotated. Rubber Bungee tensioners were used by some. Others had an extra set of wheels with the chains permanently mounted and put on tight before the tire was fully inflated. ( The cross chains were still loose). Most of the Jicarilla had 2WD PU's with the latter arrangement.
When they were confronted with a real narrow place that mandated that they kept it in a straight line he said to grab a few clicks of emergency brake. This shifted enough power to the front so as to drag the rear straight behind the front wheels. This worked on my '69 Scout and later with my HD Half 1100 Series IH PU. This kept me from certain disaster several times.
Never heard of anyone having trouble with the chains damaging anything underneath the trucks. None of them had lift kits either.
--
Jarhead
FROM: Roger Brown
SUBJECT: Re: Tire Chains
David & Ann wrote:
Thanks, everyone, for the advice/experience. I'm only running with the chains on the snow covered trails (and my driveway when I turn the truck around). I wouldn't be able to get up my hill without them. So far, I've been able to climb the hill with just the rear chains, but the snow isn't very deep yet. I may need to add another set of chains to the front if we get more snow. I'll make sure to check the brake lines for clearance first.
Airing the tires down can help, too. I find that running around 18-20 psi does wonders for snow and ice traction and you can still do freeway speeds if needed.
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