How to Replace the Upper or Lower Radiator Hose on a 2018 Nissan Maxima
Step-by-step instructions with required tools, parts list, coolant refill/bleed tips, and safety checks for 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023
How to Replace the Upper or Lower Radiator Hose on a 2018 Nissan Maxima
Step-by-step instructions with required tools, parts list, coolant refill/bleed tips, and safety checks for 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023
🔧 Maxima - Radiator Hose Replacement
On your Maxima, the radiator hoses carry coolant between the engine and radiator. Replacing a leaking, swollen, or cracked hose prevents overheating and coolant loss.
Quick check: Are you replacing the upper hose (top of radiator) or the lower hose (bottom of radiator)? I’ll include steps for both below.
Difficulty Level: Intermediate | Estimated Time: 1.0-2.5 hours
⚠️ Safety & Precautions
- ⚠️ Never open the coolant cap on a hot engine; wait until fully cool.
- ⚠️ Support the car with jack stands if you lift it; never rely on a jack alone.
- ⚠️ Coolant is toxic—keep it off skin, paint, and away from pets; clean spills immediately.
- ⚠️ Keep hands/tools clear of the cooling fans; they can turn on unexpectedly.
- ⚠️ Battery disconnect is not required for this job, but keep tools away from the battery terminals.
🔧 Required Tools
You'll need the following tools for this repair:
- Safety glasses
- Nitrile gloves
- Catch pan (at least 10-quart)
- Floor jack (rated 2-ton minimum)
- Jack stands (rated 2-ton minimum)
- Wheel chocks
- Flat-blade screwdriver
- Hose clamp pliers (specialty)
- Pick tool (small hook pick)
- Slip-joint pliers
- 10mm socket
- 3/8" drive ratchet
- 3" extension
- Funnel (spill-free coolant funnel kit) (specialty)
- Trim clip removal tool
- Shop towels
🔩 Required Parts
HowToo sells all the parts you need for this repair:
- Radiator hose (upper) - Qty: 1
- Radiator hose (lower) - Qty: 1
- Radiator hose clamps - Qty: 2
- Engine coolant (Nissan Blue long-life coolant, premixed 50/50) - Qty: 1-2 gallons
📋 Before You Begin
- Park your Maxima on level ground, set the parking brake, and place wheel chocks behind the rear wheels.
- Let the engine cool completely (upper radiator hose should feel cool, not warm).
- Set the HVAC to HOT and fan on LOW later during bleeding (this helps push air out through the heater core).
- Place a catch pan under the radiator area before loosening anything.
🔨 Step-by-Step Instructions
Follow these steps in order:
Step 1: Remove the engine cover and gain access
- Open the hood and remove the plastic engine cover by pulling it upward (it’s held by rubber grommets).
- If access is tight at the radiator end, remove the upper air duct/cover fasteners as needed using a 10mm socket and ratchet.
Step 2: Relieve any residual pressure (engine cold)
- Place a thick shop towel over the coolant cap.
- Slowly loosen the cap to the first stop to release any pressure, then remove it fully.
Step 3: Drain enough coolant to get below the hose level
- Position the catch pan under the radiator drain area.
- Open the radiator drain cock (if accessible) by turning it by hand or with a flat-blade screwdriver (gentle—plastic can strip).
- Drain until the coolant level is below the hose you’re replacing (upper needs less draining than lower).
- Close the drain cock snugly by hand (do not overtighten plastic).
Step 4: If replacing the lower hose, raise the front of the car (optional but helps)
- Lift the front using a floor jack (rated 2-ton minimum) at the proper front jacking point.
- Set the vehicle onto jack stands (rated 2-ton minimum) and verify stability.
Step 5: Remove the old hose clamps
- Locate the two clamps for the hose you’re replacing (one at each end).
- If you have spring clamps: squeeze and slide the clamp back using hose clamp pliers (specialty). Spring clamps snap—keep a firm grip.
- If you have screw-type clamps: loosen using a flat-blade screwdriver (or 10mm socket if it has a hex head).
Step 6: Break the hose loose without damaging the fittings
- Twist the hose gently at the end to break the seal.
- If it’s stuck, carefully work around the edge with a pick tool (small hook pick) to let air in between the hose and the neck.
- Pull the hose off and aim it into the catch pan to control the spill.
- If there’s a small bypass/bleed hose attached (varies by routing), remove it with slip-joint pliers and transfer it to the new hose if applicable.
Step 7: Prep the fittings and install the new hose
- Wipe the radiator neck and engine-side neck clean with shop towels.
- Slide the clamps onto the new hose before installing the hose.
- Push the new hose fully onto each neck until it seats against the stop/bead.
- Reposition the clamps to the same location as original (behind the bead on the neck).
Step 8: Tighten/position clamps correctly
- Spring clamps: release using hose clamp pliers (specialty) so the clamp sits square and centered.
- Screw-type clamps: tighten with a flat-blade screwdriver until snug and the hose cannot rotate by hand.
Step 9: Refill coolant
- Install a funnel (spill-free coolant funnel kit) (specialty) at the coolant fill point.
- Refill with Nissan Blue long-life coolant, premixed 50/50 until full.
- Fill the coolant reservoir to the MAX line.
Step 10: Bleed air from the cooling system
- Start the engine and let it idle.
- Set HVAC to HOT and fan to LOW.
- Watch the funnel level; add coolant as the level drops.
- When the thermostat opens, you should feel the upper hose get hot and see steady flow in the funnel.
- If your Maxima has a coolant air-bleed screw near the coolant outlet: open it carefully using a flat-blade screwdriver until coolant flows without bubbles, then close it snugly.
- Let it idle until bubbles stop and the heater blows consistently hot.
Step 11: Final reassembly and cleanup
- Turn the engine off and let it cool.
- Remove the funnel, install the coolant cap securely, and reinstall any ducts/covers using a 10mm socket and ratchet.
- Reinstall the engine cover by pressing it down onto the grommets.
- If lifted, lower the vehicle safely using the floor jack (rated 2-ton minimum).
✅ After Repair
- With the engine running and fully warm, inspect both ends of the new hose for seepage.
- Verify the heater output is hot and stable (a weak/ cold heater can mean trapped air).
- After the first drive and full cool-down, recheck the coolant reservoir level and top off to MAX as needed.
- Look under the car the next morning for any coolant drips.
💰 DIY vs Shop Cost
Shop Cost: $250-$550 (parts + labor)
DIY Cost: $45-$140 (parts only)
You Save: $205-$410 by doing it yourself!
Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 1.0-2.0 hours.
🎯 Ready to get started?
HowToo makes it easy: same-day/2-day shipping on every part, plus all the tools and specialty tools you need! Check out the parts and tools sections below to add everything to your cart.


















