By Greg Illes
In 2015, we were fortunate to be able to take off for several months to tour Alaska and Canada. While most of the main roadways were paved for the greatest part of our 14,000-mile journey, there were some stretches of gravel and dirt to contend with.
Our towing setup is pretty typical: a motorhome towing a smaller vehicle, in our case a ’96 Ranger 4×4 pickup. We felt that we’d had pretty extensive experience, having already put 40,000 miles or so on this configuration, with many miles of mountain and desert dirt roads among them. But, as with many other factors in an Alaska journey, there are big differences.
Firstly, our Canada-Alaska trek found us on a lot of well-constructed dirt roads. What this meant was that instead of creeping along on an old desert mining road full of ruts, we were buzzing along fairly swiftly on well-graded dirt and gravel.
Secondly, due to either weather or maintenance, literally hundreds of miles of Canada and Alaska dirt roads are wet. Not muddy-wet (mostly), but certainly not dusty.
The end result was that we spent hours and hours flying along at 40, 50, even 60 mph, with a variable trailing fog of dirt, dust, rock chips and such.
We’ve been accustomed to getting out of the coach after a few miles of desert road and finding our toad (“Ralph”) all covered with dust. But absolutely nothing prepared us for the first stop after a hundred miles of wet Dempster Highway in the northern Yukon Territory. It was as if Ralph had been sprayed with a brown undercoating material, head-to-toe.
At first, we just thought it comical. We washed off the windows and boogied on down the road. What we didn’t realize was the insidious nature of the problem. Several times we were able to see other vehicles from a distance, and we noticed that behind the truck/RV was a billowing brown fog of “mud dust”. We remarked on it, and assumed (very incorrectly) that it would cover only the outer surfaces of anything being towed (see the photo). In reality, that muddy fog crept in everywhere that a breeze could blow. Once inside a nook or cranny, the fog settled to mud and then dried into a hard cake of dirt.
The first problem cropped up with jamming brakes. Small rocks had lodged behind Ralph’s front wheel bearing seals and allowed dirt into the bearings. This cocked the wheels against the calipers and caused the brakes to drag. At this point I began to notice the under-body chassis and the entire engine compartment were thick with hardened, caked mud, congealed from the muddy fog.
There were more failures over time — bad alternator, slipping drive belt, clogged-up radiators. It’s now a year later and I’m still cleaning dirt cakes out of tiny spaces here and there. This is a very long, sordid tale, but it has a major lesson and caveat: The faster you go on a dirt road, the more that bad things happen. Mud guards and such are of limited value (if any) because the “fog” just blows around them. If you can slow to below 35 mph, the trailing cloud of debris will be much smaller, and the damage much less. If you can’t slow down or don’t want to, consider driving the vehicles separately until better road conditions present themselves.
One other warning: After towing on dirt for long distances, it’s a really good idea to inspect and wash out or blow out the engine compartment.
Greg Illes is a retired systems engineer who loves thinking up RV upgrades and modifications. When he’s not working on his motorhome, he’s traveling in it. You can follow his blog at www.divver-city.com/blog.