My Cart
Your Shopping Cart is Empty
McLaren 720S Common Issues: What Independent Specialists See Most Often
The McLaren 720S is one of the most technically advanced supercars ever built — a carbon-tubbed, twin-turbo V8 supercar that delivers 710 horsepower in a package weighing under 3,200 pounds. At Foreign Automotive in Kitchener-Waterloo, we’ve been servicing McLarens for years as the only authorized Thorney Motorsport Independent Specialist for McLaren in Canada. Owners from across Ontario and the GTA bring their 720S coupes and Spiders to our Kitchener shop because we know exactly what these cars need — and we’ve seen firsthand which McLaren 720S common problems show up most often.
If you own a 720S or are considering buying one on the used market, this guide covers the most frequent issues we diagnose and repair, what they cost to fix, and how to keep your car running the way McLaren engineered it to.
1. Door Strut and Dihedral Hinge Failure
The 720S’s signature dihedral doors are visually stunning, but the gas struts and hinge mechanisms are one of the most common failure points we see. Owners typically notice the door not staying up on its own, dropping under its own weight, or making a popping sound when opening. In some cases, the hinge bushings wear out and the door begins to sag at the rear edge.
What we see at the shop: Failed gas struts (part numbers 13NA086CP and 13NA087CP for left and right), worn hinge pins, and contaminated hinge grease. We replace the struts as a pair to keep travel even, then re-grease and adjust the hinges. Repair cost in our Kitchener shop typically runs $1,200–$2,400 depending on whether the hinges themselves need rebuilding.
2. Infotainment and IRIS System Glitches
The 720S uses McLaren’s IRIS infotainment system, and it has a well-documented reputation for being temperamental. Common complaints include the screen freezing on startup, the reverse camera failing to display, Bluetooth dropping out, and the navigation system crashing mid-route.
Most of the time these are software-related faults that respond to a full system reflash. Occasionally we trace the problem to a failed central processor module or a wiring harness chafe behind the dash. We have full McLaren diagnostic equipment in-house, so we can pull fault codes McLaren-specific scan tools see — something most general European shops can’t do.
3. Coolant Leaks from Hoses and Crossover Pipes
The M840T 4.0L twin-turbo V8 in the 720S runs hot, and over time the coolant hoses and crossover pipes can crack, weep, or develop pinhole leaks — especially the ones that route through the engine bay where heat soak is highest. This is a particularly important issue for Ontario owners, because thermal cycling between summer heat and our cold winter starts accelerates rubber and seal degradation.
Warning signs: Sweet smell after a drive, low coolant warning on the dash, white residue around hose fittings, or a small puddle in the garage. Catching this early matters — running a 720S low on coolant can warp the aluminum cylinder heads, and that turns a $600 hose job into a $20,000+ engine repair.
4. Suspension Hydraulic Accumulator Failure
The 720S uses Proactive Chassis Control II (PCC II) — an interconnected hydraulic suspension system that replaces traditional anti-roll bars with cross-linked dampers and pressurized accumulators. It’s brilliant when it works, but the high-pressure accumulators have a finite service life, typically 50,000–80,000 km depending on use.
When an accumulator starts to fail, owners report the ride becoming harsh and choppy, a noticeable lean in corners, or the suspension going into limp mode with a warning light. We test accumulator pressure on our equipment and replace as needed. This is exactly the kind of work that benefits from an independent specialist — dealers will often quote complete suspension replacements when only the accumulators need attention.
5. Carbon Ceramic Brake Wear and Caliper Issues
The 720S comes standard with carbon ceramic brakes, and while the rotors themselves last a long time (often 100,000+ km of street driving), the calipers can develop sticking pistons, and the pad sensors are prone to false readings. Track-driven cars wear pads dramatically faster — we’ve seen owners come in needing pads at 8,000 km after a few HPDE weekends at Canadian Tire Motorsport Park.
We use OEM McLaren pads and have the proper tools to bed them in correctly. A full brake service on a 720S in Kitchener typically runs $3,500–$6,500 depending on whether rotors are needed.
6. Spider Roof Mechanism Faults
If you own a 720S Spider, the retractable hardtop is a marvel of engineering — and a marvel of complexity. The most common Spider-specific issue we see is the roof getting stuck mid-cycle, usually due to a hydraulic pump issue, a misaligned microswitch, or low fluid in the roof hydraulic reservoir. Less commonly, the rear window mechanism fails independently of the roof itself.
These issues often look intimidating but most are repairable in-shop without a complete roof replacement — provided the diagnosis is done by someone who knows the McLaren-specific procedure for indexing the roof position sensors.
7. Battery Drain and Long-Term Storage Issues
This isn’t a defect so much as a reality of supercar ownership. The 720S has a significant parasitic draw, and if it sits for more than two weeks unplugged, the battery will go flat. A flat battery on a 720S isn’t a simple jump-start either — the doors won’t open, the central locking won’t respond, and the car needs to be coaxed back to life through a specific procedure to avoid module faults.
Our recommendation for Ontario owners who store their 720S for the winter: use a CTEK or McLaren-approved battery maintainer, plugged in continuously. We sell the right units and can fit the correct connector for your car.
Need McLaren 720S Service in Ontario?
Foreign Automotive is Canada’s authorized Thorney Motorsport Independent McLaren Specialist, providing McLaren service in Toronto & the GTA. Book your 720S in for diagnosis, service, or pre-purchase inspection.
Contact Us(519) 894-9551 | sales@foreignautomotive.ca
Why Bring Your McLaren 720S to Foreign Automotive
We’re not a general European shop dabbling in McLaren — we’re the only Thorney Motorsport authorized Independent McLaren Specialist in Canada. That means factory diagnostic access, technician training direct from a McLaren motorsport partner, and access to OEM parts and recall information. We also have an in-house Dynapack AWD dyno for performance verification, full alignment equipment calibrated for supercar specs, and our ECC ECU tuning partnership for owners who want to unlock more from their M840T engine.
Owners drive to our Kitchener shop from Toronto, Mississauga, Oakville, Hamilton, Guelph, Cambridge, and across Ontario because they know their car will be diagnosed and repaired correctly the first time — without dealer overhead pricing.
Frequently Asked Questions
How reliable is the McLaren 720S overall?
The 720S is more reliable than its predecessors (650S, 12C) but still requires meticulous specialist care. The drivetrain itself is robust; most issues we see are around accessories, electronics, and hydraulic systems.
What is the service interval for a McLaren 720S?
McLaren recommends an annual service or every 16,000 km, whichever comes first. For Ontario owners who store the car in winter, we recommend a pre-storage and post-storage check on top of the annual service.
Can you do warranty-eligible work on a McLaren 720S?
As an independent specialist, factory warranty work must be done at a McLaren franchise dealer. However, we can perform all out-of-warranty repairs, modifications, and routine service without affecting any extended service contracts. We’ll always advise honestly on what should go to the dealer versus what we can handle.
How much does a major service cost on a McLaren 720S in Kitchener?
A standard annual service at Foreign Automotive typically runs $2,200–$3,800 depending on what’s due (filters, fluids, brake fluid flush, coolant inspection, etc.). Major services that include spark plugs and additional inspections run higher.
Do you offer pre-purchase inspections on McLarens?
Yes — this is one of the most valuable services we provide. A used 720S PPI at Foreign Automotive includes a full mechanical, electrical, and cosmetic assessment, plus a complete fault-code scan with McLaren-specific diagnostic equipment. The cost is a fraction of what a missed issue could cost you after purchase.
Foreign Automotive — Your trusted European and exotic car specialist in Kitchener-Waterloo, serving Ontario since 1992.
0 comments