How Do You Change Oil in a Craftsman Riding Lawn Mower? (Step-by-Step Guide)

What You Need Before You Start (Tools & Supplies)

Gathering everything before you begin prevents mid-job interruptions and reduces the chance of spills or stripped hardware.

• Drain pan (2-quart capacity minimum)
• Socket wrench set with 3/8-in. or 1/2-in. drive (drain plug size varies by engine)
• Replacement drain plug washer (aluminum or rubber, matches your drain plug thread)
• Correct motor oil — SAE 30 or 10W-30; see the capacity table below for quantity
• Replacement oil filter (optional but recommended; match to your engine part number)
• Oil filter wrench (if changing the filter)
• Funnel with a flexible neck
• Oil extractor / siphon pump (alternative to drain plug removal on models with limited underdeck clearance)
• Clean rags and nitrile gloves
• Sealable container for used oil transport to a recycling point

Note the distinction between pre-2017 Sears-era Craftsman models and post-2017 Stanley Black & Decker-era models. Deck geometry differs — older models often provide easier drain plug access, while newer models may benefit from an oil extractor inserted through the dipstick tube.

Identify Your Craftsman Engine Type and Oil Capacity

Engine brand and displacement determine both oil capacity and oil filter location. Using the wrong fill volume causes engine damage — overfilling is as harmful as running it low.

How to Find Your Engine Model Number

• Briggs & Stratton engines: The model, type, and code numbers are stamped on a metal tag or printed directly on the valve cover, typically on the top or side of the engine block.
• Kohler engines: The model and spec number appear on a decal affixed to the engine shroud.
• Craftsman mower model number: Located on a sticker under the seat or on the frame near the left rear wheel. Enter this at craftsman.com or cross-reference at the engine manufacturer’s site to confirm engine specs.

Common Craftsman Engine Variants at a Glance

Temperature rule: Use SAE 30 when ambient temperatures stay above 40°F. Use 10W-30 for variable or cooler conditions. Modern Briggs & Stratton engines explicitly approve synthetic 5W-30 as a full-season alternative per Briggs & Stratton owner manual guidance — this is the easiest all-climate choice if your engine is a post-2010 Briggs model.

Always confirm capacity against the dipstick after filling — the numbers above are typical, not universal across every Craftsman trim level.

Step-by-Step: How to Drain and Refill the Oil in a Craftsman Riding Mower

Step 1 — Warm the Engine (2–3 Minutes)

Start the mower and let it idle for 2–3 minutes. Warm oil flows faster and carries more contaminants and combustion byproducts out of the engine during the drain. Do not run it longer — hot oil causes burns.

Step 2 — Shut Off and Secure the Mower

Turn the ignition off. Set the parking brake. Pull the spark plug wire off the spark plug tip and tuck it away from the plug — this prevents accidental engine startup while you work underneath the deck.

Step 3 — Position the Drain Pan

Roll the drain pan under the right or left front side of the engine deck. On most Craftsman riding mowers, the oil drain plug sits on the underside of the engine block, accessible from the front or side of the mower without tilting it.

Pre-2017 Sears-era models: Drain plug is usually forward-facing and easy to reach with a 3/8-in. socket.
Post-2017 Stanley Black & Decker-era models: Some deck configurations place the plug closer to the center — use an extendable socket or an oil extractor via the dipstick tube if clearance is tight.

Step 4 — Remove the Drain Plug

Use the correct socket to loosen the drain plug counterclockwise. Once loose, remove it by hand, keeping your fingers ready to move the plug away from the oil stream. Let the oil drain completely — this typically takes 3–5 minutes. Do not rush; residual old oil left in the sump shortens the effective life of the fresh fill.

Oil extractor alternative: Insert the extractor hose into the dipstick tube and pump out the oil without removing the drain plug. This method works well on models with low deck clearance and eliminates the risk of cross-threading the plug on reinstallation.

Step 5 — Inspect and Reinstall the Drain Plug

Wipe the drain plug threads clean. Replace the crush washer or O-ring — reusing a deformed washer is a common cause of post-change oil leaks. Thread the plug in by hand first to avoid cross-threading, then torque it snug with your socket wrench. Do not overtighten — typical torque is 14–18 ft-lb on Briggs engines; consult your engine manual for the exact spec.

Step 6 — Change the Oil Filter (Recommended — See Next Section)

If changing the filter, do it now before adding fresh oil. Instructions are in the dedicated section below.

Step 7 — Add Fresh Oil

Remove the oil fill cap (marked with an oil-can symbol on the engine top). Insert your funnel and pour in approximately 80% of the rated capacity first — for example, 38 oz if the engine takes 48 oz total. This prevents overfill while accounting for oil retained in galleries and a new filter.

Step 8 — Check the Dipstick

Pull the dipstick, wipe it clean, reinsert fully, then pull again. The oil film should sit between the ADD and FULL marks. Add oil in small increments — 2–4 oz at a time — until the level reads at or just below FULL. Overfilling above the FULL mark causes oil to foam and enter the air intake, which can damage the engine.

Step 9 — Reconnect and Run

Reinstall the oil fill cap. Reconnect the spark plug wire. Start the engine and let it idle for 2 minutes. Shut it off and check under the deck for any seepage around the drain plug. Check the dipstick one final time — level typically drops slightly as oil circulates and fills the filter — and top off if needed.

How Often to Change Oil in a Craftsman Riding Mower

Craftsman and Briggs & Stratton maintenance schedules specify an oil change every 50 hours of operation or once per season, whichever comes first. Change oil after the first 5 hours on a brand-new engine to flush break-in metal particles.

How to Change the Oil Filter at the Same Time (Recommended)

Replacing the oil filter during every oil change is best practice — used filter media holds roughly 4–6 oz of dirty oil that otherwise re-circulates with the fresh fill.

Locate the Filter

• Briggs & Stratton single-cylinder (500–700 series): Many entry-level Craftsman models in this range do not have a spin-on oil filter — check your engine spec sheet. If a filter is present, it sits on the lower side of the engine block.
• Briggs & Stratton V-twin and Kohler 7000 series: Spin-on filter is typically mounted on the lower front or lower side of the engine block, accessible from underneath or from the side of the deck.

Remove the Old Filter

Use an oil filter wrench to break the filter loose counterclockwise. Position the drain pan under the filter before loosening — it holds residual oil. Once off, wipe the filter mounting surface clean and check that the old rubber gasket came off with the filter (a stuck old gasket causes leaks if a new one is installed on top of it).

Install the New Filter

1. Apply a thin film of fresh motor oil to the new filter’s rubber gasket.
2. Thread the filter on by hand until the gasket contacts the mounting surface.
3. Tighten an additional half to three-quarter turn by hand — do not use a wrench for final tightening on spin-on filters.

Oil capacity adjustment: A new filter absorbs approximately 4–6 oz of oil on first startup. After running the engine for 2 minutes and rechecking the dipstick, expect to add a small top-off amount.

Stuck Filter

If the filter is seized, use a strap-style oil filter wrench for maximum grip. As a last resort, drive a screwdriver through the filter body for leverage — the filter will be destroyed in removal, which is acceptable since it is being replaced.

Correct Oil Type and Capacity by Craftsman Engine Variant

Use the table below as a quick reference. Confirm against your engine owner’s manual before purchasing oil.

• SAE 30: Conventional single-grade; correct for steady warm-weather use above 40°F.
• 10W-30: Multi-grade; handles cold morning starts and warm operating temps — the safest all-around choice if you are unsure.
• Synthetic 5W-30: Approved in modern Briggs & Stratton engines per Briggs & Stratton owner manual guidance. Flows better at cold starts and holds up well under heat. Extended drain intervals (up to 100 hours) may apply when using synthetic — consult your specific engine manual.
• Do not use 10W-40 or heavier multi-grades in Briggs single-cylinder engines — thicker oil restricts flow at startup and increases wear.

How to Dispose of Used Lawn Mower Oil Safely

Used motor oil is a regulated waste in every U.S. state. Pouring it on the ground, into storm drains, or into household trash is illegal and contaminates groundwater.

Correct Disposal Process

1. Pour the used oil from your drain pan into a sealable container — the empty oil jug you just opened works perfectly.
2. Do not mix used oil with other fluids (gasoline, antifreeze, brake fluid) — contaminated oil cannot be recycled and must be treated as hazardous waste at higher cost.
3. Transport the sealed container to a used-oil recycling drop-off. AutoZone, O’Reilly Auto Parts, and Advance Auto Parts all accept used motor oil at no charge under their published recycling programs. Most municipal transfer stations and some Walmart automotive centers also accept it.
4. Confirm drop-off hours before you go — some locations have volume limits or accept oil only during specific hours.

The U.S. EPA estimates that oil from a single oil change, if dumped improperly, can contaminate one million gallons of drinking water. Proper recycling converts used oil into re-refined base stock or industrial fuel.

Frequently Asked Questions

How do I know what engine my Craftsman riding mower has?

Check the engine shroud or valve cover for a stamped or printed model number. On Briggs & Stratton engines, look for a three-part model/type/code number on the top or side of the block. On Kohler engines, a decal on the engine shroud shows the model and spec. Enter your Craftsman mower’s model number (found on a sticker under the seat) at craftsman.com to pull the full engine specification.

Can I use an oil extractor instead of removing the drain plug on a Craftsman riding mower?

Yes. Insert the extractor hose through the dipstick tube and pump out the old oil. This method is especially practical on post-2017 Craftsman models where deck geometry limits drain plug access. It does not replace the drain plug washer, so inspect the plug and washer annually regardless. The extractor method is slower but eliminates cross-threading risk.

Should I change the oil filter every time I change the oil?

Recommended, yes. The filter retains 4–6 oz of contaminated oil that dilutes the fresh fill on startup. On Briggs & Stratton single-cylinder (500–700 series) engines used in many entry-level Craftsman riders, a spin-on filter may not be present — confirm by consulting your engine spec sheet. On V-twin Briggs and Kohler 7000-series engines, a filter is standard and should be replaced at each oil change interval.

How often should I change the oil in a Craftsman riding lawn mower?

Every 50 hours of operation or once per mowing season, whichever comes first, per Craftsman and Briggs & Stratton maintenance schedule documentation. On a brand-new engine, perform the first oil change after 5 hours to flush metal particles from the break-in period. If you mow infrequently, change oil at the start of each season regardless of hours — oil degrades with age even when the engine sits unused.