Checking your fisher plow hydraulic hoses for cracks or leaks is probably the last thing you want to do on a freezing Tuesday night, but it's way better than having a line blow while you're halfway through a commercial parking lot. If you've spent any time behind the wheel of a plow truck, you know that hydraulic issues don't happen when it's sunny and fifty degrees. They happen at 3:00 AM in a blizzard when you're tired, cold, and just want to finish your route.
The hoses on a Fisher setup are the lifeblood of the whole operation. Without that pressurized fluid moving through the lines, your blade is just a heavy piece of dead weight hanging off the front of your truck. Understanding how these hoses work, why they fail, and how to swap them out quickly can save you a massive headache when the snow starts piling up.
Why These Hoses Give Out
You might think a thick rubber hose reinforced with steel braid would last forever, but the environment under the front of a truck is brutal. Your fisher plow hydraulic hoses are constantly being flexed, frozen, and pelted with road salt. Over time, that rubber starts to lose its elasticity.
One of the biggest enemies of these lines is abrasion. As the plow moves up and down or angles from side to side, the hoses shift. If they're rubbing against the lift frame or a sharp edge on the A-frame, they're going to wear thin. Eventually, that thin spot becomes a pinhole leak, or worse, a full-on blowout.
The cold doesn't help either. When the temperature drops well below zero, the rubber gets stiff. If you try to force the plow to move before the fluid has had a chance to warm up a bit, that internal pressure can find the weakest point in a brittle hose and pop it like a balloon.
Identifying a Failing Hose
Sometimes a failure is obvious—you'll see a literal geyser of blue or red hydraulic fluid spraying across your hood. But more often, the signs are subtle. You should get into the habit of doing a "walk-around" before you head out for the night.
Look for "wet" spots on the hoses. If a hose looks shiny or oily, it's likely weeping fluid. Grab a rag and wipe it down; if the oil comes back after a few minutes of use, you've got a problem. Also, keep an eye out for bubbling or blistering on the outer jacket. This usually means the inner lining has failed and the high-pressure fluid is starting to push through the reinforcement layers. If you see a bulge, don't wait. That hose is a ticking time bomb.
The Danger of Pinhole Leaks
I can't stress this enough: never use your hand to find a hydraulic leak. It might seem tempting to run your finger along a hose to find where it's wet, but if there's a pinhole leak under high pressure, it can actually inject hydraulic fluid directly under your skin. It's called an injection injury, and it's a medical emergency that can lead to losing a finger or worse. Use a piece of cardboard or a piece of wood to scan the hose if you suspect a tiny leak.
Getting the Right Replacement
When it's time to buy new fisher plow hydraulic hoses, don't just grab the cheapest thing you find at a general hardware store. Fisher plows use specific lengths and fitting sizes depending on the model—whether you're running a classic Minute Mount, an HDX, or one of the newer stainless-steel V-plows.
The fittings are the most important part. Most Fisher setups use a specific thread type (often JIC or NPT), and getting the wrong one will just result in a stripped thread or a leak that won't stop no matter how hard you crank it. It's usually worth it to buy OEM or high-quality aftermarket hoses designed specifically for snow plow duty. These are typically rated for higher pressures and have better weather resistance than a generic hydraulic line.
Measuring for Success
If you're in a pinch and need to have a local shop crimp a new hose for you, make sure you bring the old one along for a measurement. You want the new hose to be the exact same length. If it's too short, it'll pull tight when you angle the plow and snap. If it's too long, it'll hang down and get pinched in the lift mechanism or drag on the ground.
The Swapping Process
Changing out a hose isn't rocket science, but it is messy. You're going to want plenty of rags and a catch pan. First, make sure the plow is either fully on the ground or securely supported by jack stands. You do not want the blade dropping on you if you disconnect a lift line.
- Relieve the pressure: This is the step most people forget. Even with the truck off, there can be residual pressure in the lines. Move the controller in all directions after the engine is off to "bleed" that pressure out.
- Clean the area: Use some brake cleaner or a rag to wipe down the fittings before you open them. You don't want salt and grit falling into the hydraulic pump.
- Use two wrenches: This is the pro tip. Use one wrench to hold the base fitting and the second to turn the hose nut. This prevents you from twisting the metal tubes or ripping the fitting right out of the ram.
- Route it carefully: When you put the new one on, follow the original path. Make sure it's not kinked.
Once the new hose is on, you'll need to top off the reservoir. Don't just use any old oil; Fisher's High-Performance Hydraulic Fluid is designed to stay liquid at crazy low temperatures. Using generic tractor fluid can make your plow run sluggishly when it's really cold.
Routine Maintenance to Save Your Hoses
If you want your fisher plow hydraulic hoses to last more than a season or two, a little preventative care goes a long way. During the off-season, some guys like to spray their hoses with a bit of silicone protectant to keep the rubber from drying out.
Another great trick is to use protective sleeves. You can buy nylon "snakeskins" that slide over the hoses. These take the brunt of the rubbing and UV damage so the rubber stays intact. If you notice two hoses rubbing against each other, a simple zip-tie (not too tight!) can keep them separated and stop them from sawing through each other.
Checking the Fittings
While you're looking at the hoses, don't ignore the metal ends. Road salt eats through everything. If the metal fittings on your hoses are looking crusty and rusted, they might seize up, making it impossible to change the hose later without replacing the whole ram. A quick dab of grease or some fluid film on the threads can save you a lot of swearing next year.
Wrapping Things Up
At the end of the day, your fisher plow hydraulic hoses are a wear item. They aren't meant to last the life of the truck. By keeping a close eye on them and replacing them at the first sign of trouble, you ensure that you're the one out there clearing snow and making money, rather than sitting in a frozen driveway waiting for a tow or a mobile mechanic.
Keep a spare hose and a couple of wrenches in your "oh crap" kit in the truck. It might take twenty minutes to swap a line in the field, but if you have the parts on hand, it won't end your night. Stay safe out there, keep the rubber side down, and keep those lines tight.