Negotiating Hills With Your RV

Hey, lets face it, most RVs, whether motorized or towable, are HEAVY. That means it is going to take extra effort to get them up hills and they'll often come down faster than you want them to. Like the "Little Engine That Could", you need a positive attitude -- and a few good driving skills and tricks.

One of the key factors is to not overload your vehicle. Be aware of the Gross Vehicle Weight Rating (GVWR) of your motorhome and the Combined Vehicle Weight Rating (CVWR) any vehicle towing a trailer. Exceeding the weight capacity puts extra strain on the drive train components and especially brakes and tires, affecting safety and handling as well as longevity.  Weigh your vehicle(s) at a truck scale, and, if you find you're overweight, reduce the load before you permanently damage your equipment or have a serious accident! Since water is pretty heavy, you can often reduce load by keeping your holding tanks empty and by reducing how much fresh water you are carrying. If you are headed out to boondock in a remote area, you want your fresh water tank full when you get there, but if you're headed to a campground with hookups, or even one where you can refill your water tank easily nearby, don't fill your fresh water tank more than about 1/4 full on the road -- just enough to meet your needs while  en route.  Unfortunately, many motorhomes come from the factory with little extra capacity for cargo.  Often they are close to being over weight even before you include water and passengers so it is really easy to exceed the weight ratings.  If you find yourself in that situation about all you can besides limiting what you carry around, is to buy a motorhome with greater weight ratings.  Although you might be able to upgrade springs and shocks so solve some ride issues, it really isn't practical to increase the weight ratings, which take into account many factors which are basic elements of the vehicle design.  While tires and springs are often the most affected by load, there are many other factors to consider, including other parts including suspension, the frame, engine, transmission, and differential which could limit the maximum weight.

There are serious consequences to attempting a hill that is too steep or too long for your vehicle. Pay attention to your vehicle. If the engine temperature starts to climb or if you feel the transmission start to slip or it begins to blow smoke, pull over before you permanently damage your engine or transmission. Repairs can be VERY costly! A lot more costly than having your RV towed to safety and repaired before major damage occurs. Of course you will have checked all the critical components at the beginning of your trip so you have confidence in your equipment when you start climbing steep hills. Remember, check all belts and hoses before each trip. Check tire pressure every day before driving. Check oil, transmission fluid, and coolant levels frequently. These routine maintenance procedures can save your trip, your vehicle, and your wallet!

If you are within acceptable weight limits, here are some tried-and-true tricks to handling the hills. First, try to "get a run at it" when you approach a hill. The more momentum (within safe limits) you have as you start up the hill, the better. This is a trick used for years by commercial truckers. If you use this trick, pay attention to the local speed limits and your speed. Its a lot better (and less expensive) to downshift going up a hill than to pay a speeding ticket!  Getting a run at hills probably won't improve gas mileage because you'll use more gas accelerating as you approach the hill anyway, but it can get you over them easier without slowing traffic behind you as badly, delaying your travel, or lugging the engine and putting unnecessary strain on the drive train.

Next, don't "lug" the engine. This puts extra stress on internal components, reduces fuel economy, and slows you down. If your vehicle as a Tow/Haul option be sure to engage it for climbing and descending hills.  If your vehicle has an Overdrive feature that can be disabled, do so for climbing and descending hills.   If the engine is lugging, downshift to a lower gear. When downshifting, keep an eye (or an ear) on the RPMs so you don't over-rev the engine, which can be catastrophic! Also carefully watch the engine temperature gauge and pull over if your vehicle begins to overheat. Turn off the automotive air conditioner as you approach a steep hill or a long grade. You will often see signs alongside the highway to remind you to do this as you approach a long or steep grade. Don't ignore them! They're not just a ploy to make you hot and want to buy cold drinks at the next convenience store.  Turning off your A/C reduces the load on the engine and eliminates the extra heat from the A/C condensor in front of the radiator.  An old time trick to increase cooling capacity when climbing hills is to turn on the heater.  Yeah, it won't be comfortable, but the heater core is actually little radiator that will help a little bit in reducing coolant temperature.  The heat that comes into the passenger compartment is heat removed from the engine's cooling system.  When listening to your engine RPMs, be aware that many RVs have a temperature controlled fan clutch on the radiator. The fan spins freely until the engine gets hot to conserve fuel, then the clutch engages to drive the fan to cool the radiator when the engine gets hot. When the fan kicks in it is usually noisy and may sound like the transmission has downshifted.  If your vehicle doesn't have a tachometer to display RPM, one can usually be added and they're not terribly expensive.  Could be a good investment toward avoiding catastrophic and expensive repairs.  Another useful gauge on some vehicles is transmission temperature gauge.  If your vehicle is equipped with one, pay attention to it and pull over before it gets to the high end of the scale.  If you don't have a transmission temperature gauge, you may be able to add an aftermarket gauge.  It can be a little pricey, but a lot less expensive than repairing or replacing a burned up transmission. When components inside the transmission begin slipping the friction generates a lot heat, which puts even more stress on components and reduces the proper functioning of transmission fluid.  It becomes a vicious cycle in which the worse it gets, the faster it gets worse.

Don't hold up traffic! Try to maintain your speed on hills. Sometimes you won't be able to maintain speed climbing a hill with a big motorhome or towing a trailer. When this happens, do your best to keep out of the way of other vehicles. Keep as far to the right as practical.  Use the "truck lane".  And take advantage of turn-outs to allow traffic to pass you. Impeding traffic more than discourteous:  it is dangerous and illegal. In California, for example, you are required by law to pull over if there are more than 4 vehicles behind you. Unfortunately, many drivers either don't know or don't care about this requirement. Because it is difficult to get going again on a steep hill, many drivers of large vehicle use that as an excuse not to pull over.  However, not only is it inconsiderate of other drivers, it often creates a safety hazard.  It is SO much better to incur the inconvenience of restarting on a hill than to cause an accident.  Many times you will be able to find a place to pull over where it won't be all that difficult getting going again.

If you climb a hill, eventually you'll be coming back down, perhaps on the other side or on your return trip. A heavy RV responds very well to gravity and you may quickly find yourself traveling faster than is legal, comfortable for the driver, or safe if you don't manage your downhill speed. DO NOT RIDE THE BRAKES! Using the brakes constantly will cause rapid wear and will also to cause them to overheat and once they've overheated they become useless. Even before reaching that stage, excessive use will cause glazing that reduces the friction between the brakes and the drums or rotors, seriously reducing stopping power. Keep in mind, brakes work by converting the kinetic energy of the vehicle into heat due to the friction between the brake pads or shoes and the rotors or drums.  When the capacity of the shoes or pads to absorb heat is reached, they stop working.   Heat builds up in the rotors or drums, causing them to warp.   Once again you may be able to downshift and let the engine help hold you back. This works well on gasoline engines and on diesels with engine or "Jake" brakes, but is not very effective on other diesels.  Just watch the RPMs so you don't over-rev the engine when you drop down a gear or two.  Also be aware of local noise restrictions that prohibit the use of "engine brakes".

If downshifting doesn't hold your speed within acceptable parameters, use the brakes to slow to about 10 MPH below your target speed, then let off the brakes until the vehicle reaches about 10 MPH above the desired speed. Then apply the brakes again and repeat this procedure until you are off the hill. The time between brake applications helps allow the brakes to cool and maintain effectiveness. This is much better than riding the brakes to try in vain to maintain a constant desired speed.

Of course, it is advisable to avoid unusually steep or long grades whenever you can. So check your route before you leave home and try to select destinations and routes that won't put unusual stress on your vehicle or you! Along that line, you will want to make sure you don't get into a situation where your vehicle is too big for the available road and you have no place to turn around! So PLAN AHEAD! Sometimes the only way to reach a chosen destination includes climbing a difficult hill. If you've had problems with your vehicle overheating, try to plan your trip so you encounter the hill during during a cooler part of the day or during the night.

Auxiliary cooling systems might be used to keep radiators cool on heavy rigs on steep grades. The one I've found very effective and fairly inexpensive is to install a way to spray water on the front of the radiator. You can sometimes make one using and old windshield washer system from a junk yard. The water evaporates and helps cool the radiator. I've seen water injection used on carburated engines. These water injection systems were originally intended to help clean carbon inside the heads and cylinders but drivers discovered they could also improve mileage and reduce engine temperature slightly. Make sure the factory fan (and fan clutch, if so equipped) and belts and water pump are in good condition. Many newer vehicles have electrically operated fans that are controlled by a thermostat. Make sure your wiring and connectors are all in good condition.

When we had engine problems with the pickup truck pulling our enclosed motorcycle trailer up a particularly nasty hill, we stopped and unloaded the motorcycles and rode them to the top of the hill to reduce the weight in the trailer.  Since each bike weights somewhere around 300 lbs, it made a big difference to offload 3 or 4 bikes.  We were in a very remote area where riding dirt bikes on the paved road wasn't likely to be a problem even though it was technically illegal.  You wouldn't want to try this on a freeway or a major highway.  Another time we switched the trailer from the truck to the motorhome until we reached the top of the hill.

I think I can! I think I can!