Quick answer: Alternator Replacement on a 2010–2015 Lexus RX is rated Advanced and takes about 2 hours. You'll need 11 tools for this job, and parts cost about $339. This guide walks you through the full job step by step, including the mistakes to avoid.
| Part Name |
Part Number |
Price |
Buy |
| Alternator |
27060-31161 |
$339.23 |
|
About prices: shown prices are typical retail averages and change frequently; cheaper alternatives may be available. Confirm the current price before buying.
💡 Pro tip: Order all parts at once to save on shipping
Step-by-Step Instructions
Follow these steps carefully
1
Prepare for Tight Access (5-hour job!)
The 2010–2015 Lexus RX350 (AL10, 3.5L 2GR-FE V6) alternator replacement: 150 Amp Denso OE with 7-groove clutch pulley. WARNING: this is the TIGHTEST access in the group — the alternator comes out through the FRONT/BOTTOM, not the top. Budget HOURS, not minutes (owners report ~5 hours). You'll need: new 150A Denso alternator (Toyota 27060-31161 — verify Japan vs Canada build by VIN), 14mm/12mm/10mm sockets, 10mm gear wrench, flat-blade screwdriver. The FSM over-specifies (coolant drain, PS pulley) — owners skip those. Disconnect the battery (remove it for better access). This is a challenging job — the tightest alternator in the group.
🔧 Mechanic's note — Ray Delgado
I disconnect the RX350 negative cable and wedge it behind the airbox — this is a five-hour alternator job in tight quarters, and I am going to be bumping that area all day. One accidental touch and the wrench becomes a welder.
2
Clear Access (sway bar, A/C lines!)
Create access: remove the skid plate (or let it hang), remove the passenger-side sway-bar end (let the bar rest on the frame), remove the stabilizer link, unbolt two A/C-line brackets at the front (the metal bulb blocks the path), remove the wheel-well plastic cover. The RX350's alternator is buried — you need room. Protect the exposed crank-sensor wires under the alternator with a rag. This is the hard part — the actual alternator swap is easy once you have access.
3
Remove Serpentine Belt
Use 14mm on the belt tensioner (pull toward passenger side) to slip the serpentine belt off the alternator's 7-groove clutch pulley. Note the routing. Optionally remove the intake brace (12mm) for more room. The 7-groove belt must align on reinstall.
🔧 Mechanic's note — Ray Delgado
I remove the RX350 serpentine belt and I label the routing with masking tape before it comes off — I have routed one from memory and gotten it wrong. The tape takes ten seconds and saves an hour.
4
Disconnect Electrical (10mm + plug)
Disconnect the wire-harness stays (10mm), the regulator plug (top-side release tab — don't force), and the charging cable (10mm bolt under the grey plastic cover). The RX350's wiring is tight — use the 10mm gear wrench for the bracket. Ensure all electrical is disconnected before unbolting. The Denso's 7-groove clutch pulley means the belt must come off first.
5
Unbolt and Extract (front/bottom!)
Remove the two 14mm mounting bolts (top is a nut, bottom is a bolt). It's a tight fit — patience. Don't damage the crank-sensor wires (protected by your rag). The 150A Denso is shared with the Highlander/Sienna/Venza 3.5L.
6
Install, Reassemble, Test
Install the new 150A Denso alternator (verify Japan/Canada build by VIN) — maneuver it in via the front/bottom path. Bolt it (two 14mm — forum-reported 32 ft-lbs, not FSM-confirmed). Reconnect the charging cable (10mm — forum 71 in-lbs) and regulator plug. Reinstall the belt (7-groove alignment), sway bar, A/C brackets, skid plate, wheel-well cover. Reconnect the battery. Test: 13.5-14.5V running. The TIGHT front/bottom extraction with sway-bar/A/C moves is the RX350's defining difficulty — the hardest alternator in the group. The 150A Denso 7-groove clutch is the spec. (Torque figures are forum-reported — not factory.)
🔧 Mechanic's note — Tom Becker
I install the RX350 alternator and torque the mounting bolts — I have snapped an aluminum ear off a bracket going by feel, and the Denso unit is too expensive to risk. The wrench is always worth the extra minute.
All Done!
Test your repair before closing everything up. If something doesn't work right, double-check your steps.
⚠️ Common Mistakes to Avoid
- • Not disconnecting the battery before starting the repair
- • Forgetting to properly torque the alternator mounting bolts
- • Neglecting to inspect the serpentine belt for wear during the replacement
