My work vehicle is a 4WD Suburban. The case that holds the chains looks like there is one pair of chains. Should the occasion arise, do I put them on the back wheels?

Somewhere (probably here) I read that 4WD should have chains on all four tires. Is that optimum? Is it necessary?

Sue

Instructions for mine says put them on the front.
I assume being able to steer is a useful feature!

Chains should go on the primary drive wheels. For a truck they go on the back. For a front-wheel drive car, mount on the front.

Serious off-roaders put chains on both the front and back of their 4x4s.

Ditto Doug.

I lived on Mt. Hood (2500-foot level) during my formative driving years. Had a '69 Mustang. I carried chains in the trunk and always got good result putting them on the rear (drive) wheels. With a rear wheel car it's also good to put some extra weight in the trunk to improve traction.

I did once add a chain to one of the front tires to get help steering when we also had a lot of ice. I think that was the storm that required me driving through the Gorge in a snowplow-led caravan on I-84, to get back to school after Christmas break.

My brother was Mr. 4x4 and rarely used chains at all. I do remember him once chaining up all four wheels on his '71 Blazer when we got 5-feet of snow in 36 hours. That was an unusual storm. His first car was a '53 Willy's with a short-block V-8.

I have chains for my 2004 Honda Element (kind of absurd for the mid-Atlantic but I can't break the habits of my Cascade Mountains days). Low-profile chains that are supposed to go on the front wheels -- the primary drive wheels in the Element's AWD system.

The front differential on a rear wheal drive 4x4 is weaker
than the rear. It is made for light duty occasional use.
You are more likely to wear and strain it
if you chain up the front only. That is why instructions
say to chain up the primary drive axle.

I have had a 4x4 swap ends with chains on the front only.
Very scary.

Chains on the rear give better traction going uphill
and keep you straight on the downhill.

The manual for my Jeep Cherokees (1984 and 2001) state to NOT put chains on the front tires. It doesn't say why but having spent extensive quality time underneath them the reason is likely to be that there's little clearance at the tie-rod end.
Simple translation- the chains will catch on something really important and you won't be steering anymore.

The vehicle's owners manual should say something about chains on your particular vehicle.

And I second the suggestion to try them on the vehicle. Do it when you have time and it's warm and don't really need them. It's 10x harder to install them when you really need them.

If I chained the front of my truck it would rip the inner fenders off. No clearance at all!

In CA during BAD BAD storms they even require 4x4s with MS tires to have chains too, unless you live there and are driving home and it's not the highway. When it's bad they just close the highway, mostly do to avalanche warning or extreme white-out conditions.

Dad's logger/surveyor friends from his Weyerhauser days were adamant that you only chained up the real wheels on pick-up trucks, whether they had 4wd or not. I took it as gospel cuz these were the guys that did it all their life for a living.

Sue, 4wd or all wheel drive? Not quite the same, and most Subies I know are AWD. They also don't have a huge amount of clearance in the wheel wells, so I'd be careful about mounting them anywhere.

"Sue, 4wd or all wheel drive?"

It has regular 2WD, Automatic 4WD, upper 4WD and lower 4WD.

Les Schwab provided the chains at the same time the tires were bought and studded.

Sue