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Traction Control: RUD Grip 4×4 Chains Review

// March 8th, 2010 // 4WD and Traction Aids, Equipment and Gear, Product Reviews, Toyota FJ Cruiser, Wheels and Tires

The mid-Atlantic region recently experienced several rather severe snow storms which left us with with more than four feet of accumulated snowfall in less than a week.  Because of the road and parking lot conditions, many businesses remained closed during that week, to include my current work location.  As a result of these closures, I had some free time on my hands and decided it would be a great opportunity to test out the FJ’s sure-footedness in some seriously heavy snow and ice conditions.  The detailed results of that testing can be found in this post, but the bottom line of my initial tests showed that the combination of long, flat skid plates and Nitto Terra Grappler tires just didn’t perform all that well in deep, wet, heavy snow.

Realizing that I required a better solution to this problem, my next thought headed to snow chains. As I mentioned in the previous traction-related article, the use of studded tires in Maryland is prohibited. Using snow chains during inclement weather, however, is perfectly legal. Since I didn’t currently own a set of chains, I began searching the Internet, in hopes of finding a set of chains that not only fit my over-sized tires, but ones that were sturdy enough to endure deep snow and mud conditions. My research led me to the “Grip 4×4″ chains, manufactured by a German company known as RUD.  Among other positive reviews, these chains were personally recommended by Bill Burke, an internationally known and well-respected off-roading spokesman and trainer. Based on these reviews and recommendations, I decided to give them a shot. For my current tire size, a 295/70R17 Nitto Terra Grappler, I ordered one set of model number 2533, the largest size offered in the Grip 4×4 series.

On a brief side note, I should point out that if you are looking for a set of snow chains, it’s best to purchase them well ahead of time. I discovered, nearly too late, that finding snow chains toward the end of the winter season is next to impossible. Snow chains, like swim wear and pumpkins, are apparently considered a seasonal item. I happened to luck out and find one set left, through an online retailer. But I was told that if they hadn’t been available, I would have been looking at September at the earliest to see a set. So if you don’t currently have a set of chains and foresee yourself needing a set, I highly recommend picking them up late fall or early winter.  Once suppliers run out, they’re usually out until the next season rolls around. Thanks to some quick shipping, I received my RUD Grip 4×4 chains less than three days later.

NOTE: Per the FJ Cruiser’s operation manual, chains are only to be used on the rear wheels, not the front. My assumption is that the space tolerances in the front, given the various independent suspension components, are simply too tight to accommodate a set of chains.

Round One:

Even though the snow had settled some since the original storms, there was still plenty left on the ground for testing purposes. In addition to the chains themselves, RUD also supplies a handy tote bag to store the chains, along with a set of laminated instructions for installation. I removed the chains from the bag, along with the instructions and promptly began the installation process. Thanks to the detailed instruction sheet, I had both chains installed in less than 15 minutes, and proceeded slowly out of the garage to begin my testing. These particular chains have an added advantage since they can be installed without moving the vehicle. However, I recommend driving a very short distance and then stopping to re-adjust the tension straps since the chains are still somewhat loose after installation.

The back pasture behind our house which was still blanketed with significant snowfall, so I decided to use that area as my proving grounds. Having done this several times before (without chains), I decided to place the transfer case in 4-wheel-drive, low gear, in hopes of improving my odds. I slowly eased the FJ into the nearest drift. Sadly, I only made it about 15 feet before I began to slip significantly. Sensing that I was losing forward momentum, I urged it forward with a bit more gas, at which point the rear tires simply began to spin and dig. In the FJ’s defense, the snow had languished for well over a week, turning any remaining powder to mushy, slushy ice. So effectively, the FJ was attempting to push its way through more than a foot of well-packed “slurpee.”  It was an exercise in frustration to say the least. But I have to give credit where it’s due. The chains continued to dig as long as I gave it gas. In fact, they dug to the point where the rear of the FJ was now sitting 6-8 inches lower than the front.

I placed the FJ in reverse and with a steady flow of gas, it began to inch its way back towards the house. However, before it reached its destination, the tires began to slip and spin again. I engaged Active Traction Control (A-Trac) but it made no difference. Engaging the rear locker also met with no results. So I decided to give it a little more gas and see if I could get enough traction to pull myself out. More gas meant more spinning but it also resulted in a slight backwards creep – I was moving again. So I gave it a little more gas and the FJ slowly began creeping backwards, spinning and digging with the rear tires, but gaining a little momentum with each passing second. This continued until the FJ eventually gained the upper hand and began moving without slipping.

My enthusiasm was short-lived, however, when I reached the garage only to discover that the passenger-side chain was hanging limply from the tire. In the wake of excess gas and wheel spin, the rubber tensioner on the outer portion of the chains had simply given up the ghost, tearing itself in half as a result of too much strain. The lack of tension on the outer ring caused the entire assembly to fall inwards, looping itself lifelessly around the rear axle. I’d like to state up front, that excess gas is not my typical approach to traversing an obstacle. I much prefer to approach each obstacle with slow, even control, which means using as little gas as possible. By using the slow approach, I suspect that the rubber tension strap would have maintained its position without damage.

But while my extraction technique may have proved too aggressive, I feel the need to point out that the RUD Grip chains are rated for more than just snow. They are also designed to be used in mud – a harsh and abrasive environment that is bound to contain large combinations of sand, stone, rock, stumps, roots and other debris. It’s also an environment where (despite the tread lightly motto), significant churning is not uncommon in order to free one’s self from slippery obstacles. I have no complaints about the chains themselves, which appear to be very well designed and seemingly quite sturdy. But using a thin rubber bungie for a tension strap makes me wonder if the manufacturer was truly considering the environments these chains would witness.

Rather than send the chains back, I began devising a plan to replace the rubber tension strap with a sturdier alternative. Since I still required tension and flexibility, the first item that came to mind was a metal spring.  The original rubber bungie came molded with two metal hooks in each end. I cut away the remaining rubber and extracted both hooks. Then I picked up an assortment of springs from the local hardware store, attempting to find a set with a small diameter but sufficient resistance to maintain the chain’s position. Without a fish scale or other tension measuring device, it was difficult to determine how much resistance the original rubber straps provided. I suspect that during normal rolling conditions, the original strap would have held up fine. But during excess wheel spin, the forces applied were clearly increased, so the replacement spring would obviously need to exceed the limitations of the original strap.

Round Two:

It took me over a week, but I finally got around to assembling the reconstructed chains and springs. The images that follow show both of the original rubber tension straps (good and broken). Using a combination of wire snips and a box knife, I cut away the original rubber strap and extracted the metal hooks from each end. I then replaced the rubber strap on both chains with a metal spring and re-attached the metal hooks. Without knowing the amount of tension applied to these straps during wheel spin, I was left with some guess work when it came to selecting springs. I managed to locate a set with a small enough diameter so as to not interfere with the tire, but in so doing, the springs were only rated for a bit over 10 pounds a piece. But I figured I’d give them a try and see how well they performed.

It only took a few minutes to re-mount the chains and I was off for round two. The depth of the snow was now less than a foot but the consistency was still pretty much slush. Since the driveway area was now bare pavement thanks to a few sunny days, I decided to approach the snowy hill in reverse this time, assuming it would make for an easier extraction if I got stuck. Once again, the FJ only managed to gain about 12 feet of ground before momentum was lost and wheel spin began. I decided to use the “gas” approach again, steadily increasing the throttle and wheel spin until I started creeping backwards again.

Round two of testing came to an audible and startling halt as an unidentified object of significant size and/or speed smacked into the underside of the FJ. I placed the FJ in drive and pulled forward back onto the pavement where I quickly discovered that the driver’s side spring and hook assembly had dislodged itself from the chains and shot forward into the unknown. I returned to the scene and spent quite some time scanning the ground for any remnants but the evidence had simply vanished. I guess it was safe to say that I needed springs with greater resistance. Without significant resistance, the springs also became overextended, losing tension and the spring loops that held the hooks in place became distended as well. So now, in addition to needing some heavier-duty springs, I also needed a way to attach the hooks to avoid potential separation.

Round Three:

With the one exception in the Vermont mountains, I’ve not experienced significant slippage in mud thus far. I suspect it’s because most of the trails and mud holes I’ve seen up till now have been on a relatively level plain. The incident in Vermont was based on a combination of mud, sand, tree roots and a rather serious incline. It is my belief that had the FJ been equipped with a good set of mud terrain tires, it would have succeeded in overcoming this obstacle. In other words, chains would not have been required.

Further analysis of the RUD chain design also has me thinking that perhaps a tension strap is not required. I am considering two possible options for the next revision: either using a much heavier-duty spring assembly with welded hooks (to prevent separation from the spring) or eliminating the spring portion altogether and replacing it with a heavy-duty carabiner or other type of closed hooking mechanism. This second option may not put as much tension on the outer chain loop, but as long as it can withstand the stress during wheel spin, it may prove to be the better of the two options.

So for now, I’m reserving final judgment on the performance of these chains until such time as I can use them without them falling off the tire. I can say, that with the exception of the weak rubber tension strap, these chains are very well designed and rugged enough, I believe, to survive both mud and snow as advertised. And for daily travel across hard-packed snow and ice, I believe the chains would perform quite well in their stock condition. But I think I’ve effectively proven that the tension created during excess wheel spin is simply too much for the current design to handle without breakage.

Unfortunately, I haven’t had an opportunity to rebuild the chains as of yet and very little snow remains at this point. Due to the resulting failure of round two, I am also now short one of the original hooks. I’m hoping that once the snow has disappeared completely, I’ll be able to successfully locate the lost spring and hook assembly, but by then, my icy test environment will effectively be gone as well. The back pasture area is completely grassed so a mud hole would have to be created for further testing. But even with an available slop pit nearby, I don’t foresee the need for chains outside the deep snow arena.

While it’s not completely unheard of for Maryland to receive snow in the March-April time frame, it is unlikely that we will see anything substantial. The weather has already taken a turn toward Spring with the average temps now in the 60s. So even if I do manage to rebuild the chains, I won’t be able to truly test them again until next Winter. I do plan to stow them on-board, however, just in case an opportunity presents itself before then. Until that day arrives, I am forced to close out this particular chapter on Traction Control. See you in the hills!

Related Links:

Traction Control: Gaining Upper Hand with Lower Foot
Traction Control: Interco TrXus MT Mud Terrain Review
RUD Grip 4×4 chain installation video
Bill Burke’s tips for using tire chains