How to Replace the Upper or Lower Radiator Hose on a 2013 Subaru Outback
Step-by-step DIY cooling system guide with tools, parts list, coolant refill/bleed tips, and leak checks for 2013, 2014
How to Replace the Upper or Lower Radiator Hose on a 2013 Subaru Outback
Step-by-step DIY cooling system guide with tools, parts list, coolant refill/bleed tips, and leak checks for 2013, 2014
đź”§ Outback - Radiator Hose Replacement
Replacing a radiator hose is mostly about working safely around coolant, removing the clamp(s), and installing the new hose without leaks. On your Outback there are two main radiator hoses: upper (top of radiator to engine) and lower (bottom of radiator to engine).
Quick questions (so I guide you perfectly): Which hose are you replacing—upper, lower, or both? And are your clamps the factory spring clamps (you squeeze them) or screw clamps (worm-gear style you tighten with a screwdriver)?
Difficulty Level: Beginner | Estimated Time: 1.0-2.0 hours
⚠️ Safety & Precautions
- ⚠️ Only work on a stone-cold engine—hot coolant can cause severe burns.
- ⚠️ Wear gloves and safety glasses; coolant is toxic and slippery.
- ⚠️ Support the car with jack stands if you lift it—never rely on a jack alone.
- ⚠️ Keep coolant away from kids/pets and dispose of it properly (most parts stores accept waste coolant).
- Battery disconnect is not required for this job.
đź”§ Required Tools
You'll need the following tools for this repair:
- Safety glasses
- Nitrile gloves
- Drain pan (at least 2-gallon)
- Spill-free funnel kit (specialty)
- Hose clamp pliers (specialty)
- Channel-lock pliers
- Flat-blade screwdriver
- Pick tool (small hook pick)
- Razor blade scraper
- Shop towels
- Floor jack (rated 3-ton minimum)
- Jack stands (rated 3-ton minimum)
- Wheel chocks
- 10mm socket
- 12mm socket
- 3/8" ratchet
- Trim clip tool
🔩 Required Parts
HowToo sells all the parts you need for this repair:
- Upper radiator hose - Qty: 1
- Lower radiator hose - Qty: 1
- Radiator hose clamps - Qty: 2
- Engine coolant (Subaru-approved) - Qty: 2 gallons
- Distilled water - Qty: 1 gallon
- Radiator cap - Qty: 1
đź“‹ Before You Begin
- Park on level ground, set the parking brake, and place wheel chocks.
- Let the engine cool completely (ideally overnight).
- Set the cabin heat to HOT (this helps coolant flow through the heater core while bleeding).
- If you’re doing the lower hose, plan to lift the front with a floor jack and support with jack stands.
🔨 Step-by-Step Instructions
Follow these steps in order:
Step 1: Confirm which hose you’re replacing
- Open the hood and locate the upper hose (top of radiator) and lower hose (bottom of radiator).
- Use shop towels to wipe the hose ends so you can see leaks/cracks clearly.
- Upper is easier; lower usually needs lifting.
Step 2: Remove the radiator cap (cold engine only)
- Place a shop towel over the radiator cap.
- Slowly turn the cap to the first stop to confirm there is no pressure, then remove it fully by hand.
Step 3: Drain coolant to below the hose level
- Position a drain pan under the radiator.
- If you need more access underneath, lift with a floor jack (rated 3-ton minimum) and support with jack stands (rated 3-ton minimum).
- If equipped with an engine under cover, remove fasteners using a 10mm socket, 12mm socket, 3/8" ratchet, and trim clip tool.
- Open the radiator drain cock by hand and drain until the coolant level is below the hose you’re removing.
Step 4: Release the hose clamps
- For spring clamps: squeeze and slide the clamp back using hose clamp pliers (specialty) or channel-lock pliers.
- For screw clamps: loosen using a flat-blade screwdriver until the hose can rotate.
- (A spring clamp is the factory clamp you squeeze to open; it maintains tension as parts heat/cool.)
Step 5: Remove the old hose
- Twist the hose at the neck to break it loose, then pull it off by hand.
- If it’s stuck, carefully work the edge with a pick tool (small hook pick) to let air in, then twist again.
- If the hose is rock-hard and won’t come off, carefully slit the hose lengthwise with a razor blade scraper and peel it off (avoid cutting the plastic/metal neck).
Step 6: Clean the hose sealing surfaces
- Wipe the radiator/engine neck clean using shop towels.
- Remove stuck rubber film gently with a razor blade scraper, then wipe again.
- Confirm the neck bead (raised ridge) is clean—this is what the clamp seals behind.
Step 7: Install the new hose and clamps
- Slide the clamp(s) onto the new hose before installing it.
- Push the hose fully onto the neck until it bottoms out.
- Position the clamp behind the bead (not on the very end) and secure it using hose clamp pliers (specialty) or a flat-blade screwdriver depending on clamp type.
- Make sure the hose is not rubbing a belt, fan, or sharp edge.
Step 8: Reinstall the under cover (if removed)
- Reinstall clips/bolts using a trim clip tool, 10mm socket, 12mm socket, and 3/8" ratchet.
- Torque to 7.5 Nm (5.5 ft-lbs) for under cover bolts.
Step 9: Refill and bleed the cooling system
- Install a spill-free funnel kit (specialty) on the radiator fill neck.
- Refill with Subaru-approved coolant (use pre-mix, or mix concentrate with distilled water as directed on the coolant label).
- Start the engine and let it idle; keep the funnel level above the radiator neck.
- As it warms up, gently squeeze the upper radiator hose by hand (gloves on) to help burp air.
- When the thermostat opens, the level may drop—add coolant as needed.
- When bubbles stop and heat blows hot, shut the engine off and let it cool fully, then top off and reinstall the radiator cap by hand.
Step 10: Fill the overflow reservoir
- Fill the coolant overflow bottle to the FULL line using the spill-free funnel kit (specialty) or carefully pour.
- Wipe any spills with shop towels.
âś… After Repair
- Start the engine and check for leaks at both ends of the hose with a flashlight (look for wetness).
- Take a 10–15 minute drive, then recheck for leaks and recheck the overflow level after the engine cools.
- If the temperature gauge rises abnormally or there’s no cabin heat, stop and re-bleed—air is likely trapped.
đź’° DIY vs Shop Cost
Shop Cost: $250-$450 (parts + labor)
DIY Cost: $40-$120 (parts only)
You Save: $130-$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?
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