2025 Toyota Sienna Engine Parts

This table covers the bearings in the connecting-rod big ends. Typical signs include a growl that rises with speed, or play in the shaft or hub. Set preload the way the notes specify. A dry or crushed bearing fails quickly. Read more

This group shows a single part: TOPLINE RBTO59.

This table covers lower / conversion gasket sets for oil-pan and related joints. Typical signs include the leaks that sent the engine or gearbox to the bench. Use every gasket the set is meant for that opening — leftover unused pieces usually belong to another configuration. Read more

This group shows a single part: TOPLINE CBSTO59.

This table covers the main bearings that support the crankshaft in the block. Typical signs include a growl that rises with speed, or play in the shaft or hub. Set preload the way the notes specify. A dry or crushed bearing fails quickly. Read more

TOPLINE supplies both parts for the 2025 Toyota Sienna.

This group includes TOPLINE TWTO59 and TOPLINE MBTO59.

This table covers the bolts that clamp the cylinder head to the block. Read more

This group shows a single part: TOPLINE HBTO59.

This table covers the head gaskets that seal the block to the cylinder head. Typical signs include seepage at the joint, a burnt-oil smell, or a leak that appears only after a long drive. Clean both flanges and torque in the sequence the notes or the manual call for. Read more

This group shows a single part: MAHLE / CLEVITE 55502.

This table covers multi-piece gasket sets for a cylinder-head job. Typical signs include the leaks that sent the engine or gearbox to the bench. Use every gasket the set is meant for that opening — leftover unused pieces usually belong to another configuration. Read more

This group shows a single part: TOPLINE HSTO59.

This table covers the Engine covers. Read more

5 Engine Cover parts for the 2025 Toyota Sienna come from 2 brands — TECHPRO and VARIOUS MFR. The "Popular" part is TECHPRO TO1228315.

This group includes TECHPRO TO1228315, TECHPRO TO1228282 and TECHPRO TO1228283 and the remaining parts above.

This table covers full gasket kits covering the joints opened in an engine rebuild. Typical signs include the leaks that sent the engine or gearbox to the bench. Use every gasket the set is meant for that opening — leftover unused pieces usually belong to another configuration. Read more

This group shows a single part: TOPLINE CGSTO59.

This table covers the exhaust valves that let combustion gas out of the cylinder. Typical signs include a circuit that will not hold, a whistle, or a code for this valve. A stuck valve is often debris. Clean the ports before installing the new one. Read more

One part is listed for the 2025 Toyota Sienna — TOPLINE EVTO59.

This table covers the gaskets between the intake manifold and the cylinder head. Typical signs include seepage at the joint, a burnt-oil smell, or a leak that appears only after a long drive. Clean both flanges and torque in the sequence the notes or the manual call for. Read more

2 Intake Manifold Gasket parts for the 2025 Toyota Sienna come from 2 brands — BECK/ARNLEY and MAHLE / CLEVITE.

Listed part numbers: BECK/ARNLEY 0376251 and MAHLE / CLEVITE MS20603.

This table covers the intake valves that let air (and fuel, on port-injected engines) into the cylinder. Typical signs include a circuit that will not hold, a whistle, or a code for this valve. A stuck valve is often debris. Clean the ports before installing the new one. Read more

3 Intake Valve parts are listed for the 2025 Toyota Sienna, from MELLING, QUALCAST and TOPLINE.

Listed part numbers: MELLING V5832, QUALCAST 1030532 and TOPLINE IVTO59.

This table covers the mounts that hold the engine to the chassis. Typical signs include a clunk on takeoff, a vibration at idle, or a separated rubber insert. Support the powertrain before unbolting a mount, and torque the fasteners in the notes. Read more

One part is listed for the 2025 Toyota Sienna — DEA / MARMON RIDE CONTROL A42154HY.

This table covers the engine oils listed by grade and specification for this engine. Typical signs include a low-oil lamp, knocking after a long interval, or oil that has gone thin and black well before the next service. Match the viscosity and spec in the notes (and on the filler cap). The tables group grades — they are not interchangeable. Read more

12 Oil parts are listed for the 2025 Toyota Sienna, from LIQUI MOLY, VALVOLINE, IDEMITSU and 2 other brands. LIQUI MOLY 20328 carries the "Popular" badge.

In the Full Synthetic grade, LIQUI MOLY, VALVOLINE, IDEMITSU and 2 other brands supply 11 parts: full-synthetic oils. A representative part number is LIQUI MOLY 20328.

The High Mileage (>75,000 Miles) section lists 1 option from IDEMITSU — oils grouped for high-mileage engines. IDEMITSU 30015121750 is listed in this group.

This table covers the heat exchangers that cool engine oil. Typical signs include oil at the cooler fittings, or coolant that looks like a milkshake. Pressure-test both circuits after a cooler swap — a leak here mixes oil and coolant. Read more

One part is listed for the 2025 Toyota Sienna — STANDARD MOTOR PRODUCTS OCK57.

This table covers the seals at the Oil Dipstick / Tube. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again. Read more

This group shows a single part: BECK/ARNLEY 0396661.

This table covers the drain plugs in the oil pan. Read more

3 Oil Drain Plug parts are listed for the 2025 Toyota Sienna, from DORMAN and REIN.

Listed part numbers: DORMAN 090038, DORMAN 090049 and REIN HWU0112.

This table covers the caps on the oil filler neck. Read more

2 Oil Filler Cap parts are listed for the 2025 Toyota Sienna, from CALORSTAT and MOTORAD.

This group includes CALORSTAT OC2312 and MOTORAD MO155.

This table covers the oil filters that screw onto this engine's filter mount. Typical signs include low oil pressure after a service, or a filter that will not spin off because the old gasket stayed on the block. Lube the new gasket and tighten to the spec on the box; a double-gasket install dumps the sump on the first drive. Read more

18 Oil Filter parts are listed for the 2025 Toyota Sienna, from VARIOUS MFR, BOSCH, WIX and 11 other brands. MOBIL M1103A carries the "Popular" badge.

In the Economy grade, VARIOUS MFR, BOSCH, FAMOUS BRAND and 3 other brands supply 7 parts: the catalog's value-priced group. A representative part number is BOSCH 72229WS.

In the High Performance / Heavy Duty grade, MOBIL and WIX supply 2 parts: grouped under the catalog's "High Performance / Heavy Duty" designation — the notes column spells out what sets them apart. A representative part number is MOBIL M1103A.

The Standard Replacement section lists 9 options from ACDELCO, WIX, BECK/ARNLEY and 6 other brands — built to original-equipment specification. ACDELCO PF1233 is listed in this group.

This table covers the Oil Level sensors. Typical signs include a warning lamp, a stored code, or a reading that drops out when the harness is wiggled. Inspect the connector and ground before replacing the sensor — wiring faults are often condemned as bad sensors. Read more

One part is listed for the 2025 Toyota Sienna — STANDARD MOTOR PRODUCTS FLS359.

This table covers the oil pans that hold the engine's oil sump. Read more

2 Oil Pan parts for the 2025 Toyota Sienna come from 2 brands — DORMAN and SPECTRA PREMIUM.

Listed part numbers: DORMAN 266004 and SPECTRA PREMIUM TOP76A.

This table covers the Oil pumps. Typical signs include noise from the pump, no pressure, or fluid that never arrives at the outlet. Prime or fill the pump as the notes require. A dry start is a common way to kill a new unit. Read more

One part is listed for the 2025 Toyota Sienna — TOPLINE OPTO59.

This table covers the chains that drive the oil pump. Read more

3 Oil Pump Chain parts for the 2025 Toyota Sienna come from 3 brands — JAPANESE OE, MELLING and PREFERRED COMPONENTS INC.

This group includes JAPANESE OE A05079AM, MELLING 1084 and PREFERRED COMPONENTS INC C1254.

This table covers the Oil Pump Chain tensioners. Typical signs include belt flutter, a chirp that returns after a new belt, or an arm that no longer damps. Replace the tensioner with the belt at higher mileage. Read more

2 Oil Pump Chain Tensioner parts are listed for the 2025 Toyota Sienna, from MELLING and PREFERRED COMPONENTS INC.

This group includes MELLING BT7064 and PREFERRED COMPONENTS INC T66361.

This table covers the Oil Pump sprockets. Read more

2 Oil Pump Sprocket parts for the 2025 Toyota Sienna come from 2 brands — MELLING and PREFERRED COMPONENTS INC.

Listed part numbers: MELLING S1325 and PREFERRED COMPONENTS INC G57020.

This table covers the pistons that travel in each cylinder. Typical signs include knock, blow-by, or a cylinder that will not hold compression. Piston work is a short-block job. Match bore, pin and ring pack in the notes — not the photo. Read more

This group shows a single part: TOPLINE PATO59H.

This table covers the rings that seal each piston to the cylinder wall. Read more

This group shows a single part: TOPLINE RSTO59.

This table covers the timing chains that keep the cams in time with the crank. Read more

3 Timing Chain parts for the 2025 Toyota Sienna come from 3 brands — JAPANESE OE, MELLING and PREFERRED COMPONENTS INC.

Listed part numbers: JAPANESE OE A05078AM, MELLING 1083 and PREFERRED COMPONENTS INC C10142.

This table covers kits that group a timing chain with the related tensioners and guides. Read more

7 Timing Chain & Component Kit parts are listed for the 2025 Toyota Sienna, from PREFERRED COMPONENTS INC, MELLING, INA and 2 other brands. MELLING 31083SX carries the "Popular" badge.

Economy: 2 parts, from PREFERRED COMPONENTS INC. A representative part number is PREFERRED COMPONENTS INC TS17142.

The Standard Replacement section: 5 options from MELLING, INA, JAPANESE OE and 1 other brand. MELLING 31083SX is listed in this group.

This group includes MELLING 31083SX, PREFERRED COMPONENTS INC TS17142 and PREFERRED COMPONENTS INC TS20142 and the remaining parts above.

This table covers the guides and dampers that keep the timing chain on its path. Read more

4 Timing Chain Guide / Damper parts for the 2025 Toyota Sienna come from 2 brands — MELLING and PREFERRED COMPONENTS INC.

Part numbers include MELLING BT7063, MELLING BG7049 and PREFERRED COMPONENTS INC R70200, among others listed above.

This table covers the tensioners that keep the timing chain taut. Typical signs include belt flutter, a chirp that returns after a new belt, or an arm that no longer damps. Replace the tensioner with the belt at higher mileage. Read more

2 Timing Chain Tensioner parts are listed for the 2025 Toyota Sienna, from MELLING and PREFERRED COMPONENTS INC.

This group includes MELLING BT7062 and PREFERRED COMPONENTS INC T66360.

This table covers the crankshaft sprockets that drive the timing chain or belt. Read more

4 Timing Crank Sprocket parts are listed for the 2025 Toyota Sienna, from MELLING and PREFERRED COMPONENTS INC.

Part numbers include MELLING S1323, MELLING S1324 and PREFERRED COMPONENTS INC G50300, among others listed above.

This table covers the gaskets that seal the valve cover to the cylinder head. Typical signs include seepage at the joint, a burnt-oil smell, or a leak that appears only after a long drive. Clean both flanges and torque in the sequence the notes or the manual call for. Read more

3 Valve Cover Gasket parts are listed for the 2025 Toyota Sienna, from BECK/ARNLEY and MAHLE / CLEVITE.

Listed part numbers: BECK/ARNLEY 0362084, BECK/ARNLEY 0362105 and MAHLE / CLEVITE VS50976.

This table covers the pressed-in bronze and cast-iron guides that align valve stems. Typical signs include oil smoke on startup, a guide that has gone oval, or a valve that no longer seats quietly. Guides are a machine-shop fit. Confirm stem diameter in the notes before ordering. Read more

TOPLINE supplies both parts for the 2025 Toyota Sienna.

Listed part numbers: TOPLINE EVGTO59 and TOPLINE IVGTO55.

This table covers the springs that close each intake and exhaust valve. Typical signs include a sagging corner, a broken coil, or a clunk from the spring pocket. Replace springs in axle pairs and inspect the seats. Read more

2 Valve Spring parts for the 2025 Toyota Sienna come from QUALCAST.

This group includes QUALCAST 325507 and QUALCAST 325508.

This table covers the Valve Spring retainers. Read more

This group shows a single part: MELLING VSR726.

This table covers the keepers that lock each valve-spring retainer to the stem. Read more

This group shows a single part: MELLING VL1100.

This table covers the seals on each valve stem that control oil into the guides. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again. Read more

One part is listed for the 2025 Toyota Sienna — TOPLINE VSSTO34.

This table covers the oil-control solenoids that command the cam phasers. Typical signs include a door or range that will not move, or a click with no motion. Confirm the command signal before replacing the actuator — a failed module looks the same. Read more

One part is listed for the 2025 Toyota Sienna — WELLS 2T1306.

This table covers the cam phaser sprockets used by the variable-valve-timing system. Read more

One part is listed for the 2025 Toyota Sienna — STANDARD MOTOR PRODUCTS VVT747.