This Audi Q8 4M used buyer’s guide covers the petrol, diesel and mild-hybrid coupe-SUV built between 2018 and 2024, not the electric Q8 e-tron or the boxier Q7 it shares a platform with. Our pick is a 2020 or later 50 TDI in S line trim, now from around £30,000, because the V6 diesel suits the car’s weight and the post-2020 cars dodge two early recalls. Walk away from any example with an unexplained air-suspension fault or a thin service file: the running costs on this car punish neglect.
What real owners say (CDE data)
CDE cross-referenced the What Car? Used Reliability review for the 2018-2024 Q8, the Auto Express common-faults list and the DVSA recall records published for the model, checked 1 June 2026.
- Most-praised aspects: ride refinement and motorway hush, cabin material quality, and the strong real-world torque of the 50 TDI diesel.
- Most-criticised aspects: air-suspension wear and four-figure repair bills, MMI screen freezes and reboots, and the cost of replacing 21-inch and 22-inch tyres.
- Reliability signal: the DVSA has issued several recalls across the run, spanning shock-absorber forks, a steering-shaft bolt, a gearbox oil leak, rear-axle fixings and a side-airbag mounting; check any specific car on the DVSA recall service by registration.
Which engine and year to buy used
The combustion Q8 launched in 2018 with the 50 TDI, a 282bhp 3.0-litre V6 diesel running a 48-volt mild-hybrid system. The 335bhp 55 TFSI petrol V6, also mild-hybrid, followed in early 2019, with 55 TFSI e and short-lived 60 TFSI e plug-in hybrids arriving from late 2020. Our view: the 50 TDI is the one to buy. It carries the car’s near 2.3-tonne kerb weight without the petrol V6’s thirst, and it is the most common used spec, so you have the widest choice. A 2020-or-later build also sidesteps the early shock-absorber recall and the later steering-shaft recall, both of which should already be closed on any car but are worth confirming. If you cover low miles and want refinement over economy, the 55 TFSI is a smoother companion in town. If you would rather have the luxury saloon that shares Audi’s V6 mild-hybrid engines, our Audi A8 D5 used buyer’s guide weighs up the same powertrains in a different body.
What you pay for a used Q8 in 2026
Pricing has settled into a wide spread. Early 2018-2019 50 TDI cars now start around £30,000, with clean 2020 examples on full Audi history sitting closer to £33,000-£38,000 depending on miles and options (Auto Trader Q8 listings, scanned 1 June 2026). The 55 TFSI petrol tends to track slightly below the diesel at the same age because buyers worry about fuel. Move to the SQ8 and the figures jump: a 2021 SQ8 TFSI Black Edition with around 25,000 miles was listed near £55,000 on the same scan. The 2023 facelift cars carry a heavy premium and remain rare on the used market, so most buyers shopping a budget under £40,000 will land on a pre-facelift 50 TDI, which is exactly where the value sits.
SQ8 and RS Q8: read the fuel before you buy
The performance versions trip people up, so be precise. The SQ8 launched in 2019 as a 429bhp 4.0-litre V8 diesel (TDI) with an electric compressor, then switched to a 500bhp 4.0-litre V8 petrol (TFSI) from summer 2020. So a 2019 SQ8 and a 2021 SQ8 are completely different cars to fuel and service: check the V5C and the badge, not just the model name. Above that sits the RS Q8, a 591bhp twin-turbo 4.0 V8 petrol from spring 2020, with a 631bhp RS Q8 Performance arriving in 2024. These are spectacular but expensive to run, with insurance at the top of the table and tyre and brake bills to match. For most P1 buyers the SQ8 and RS Q8 are heart-over-head buys; budget for the consumables before the badge tempts you.
Air suspension, MMI and the 48-volt quirks
Three areas decide whether a used Q8 is a good buy. First, the adaptive air suspension. Springs can leak, compressors get noisy and ride-height sensors fail, leaving the car sitting unevenly; replacing an air spring or compressor runs into four figures, so a car that drops overnight or warns on start-up is a price-negotiation point at best and a walk-away at worst. Second, the MMI touchscreen infotainment, which on both pre- and post-facelift cars can freeze, reboot at random or lose Bluetooth; a software update often clears it, but test every screen function on the test drive. Third, the 48-volt mild-hybrid system, which is generally dependable but relies on a healthy auxiliary battery and 12-volt battery; a tired battery can throw mild-hybrid and stop-start faults that look alarming but are cheap to fix. Auto Express also notes brakes grinding or squealing as a common complaint, so listen on the test drive.
AdBlue, DPF and the 50 TDI diesel checks
If you buy the 50 TDI, treat it as a proper diesel. It needs AdBlue top-ups between services; the dashboard counts down range and will refuse to restart if you ignore the warnings, so check the tank has been kept filled and that no one has tampered with the system. The diesel particulate filter (DPF) hates a life of short urban trips: a car used only for the school run can clog its DPF and trigger expensive regeneration or replacement. Buy a diesel Q8 that has seen regular longer runs, and ask to see evidence. On the test drive, a cold start should be clean, with no clouds of smoke and no engine-management light. A 50 TDI that has lived on motorways with a stamped service book is the low-risk choice; one with a thin history and town-only mileage is not.
Running costs: tyres, tax, servicing and insurance
This is where the Q8 separates committed owners from optimists. The smallest factory wheels are large, and most cars wear 21-inch or 22-inch rims, so a set of premium tyres runs to hundreds of pounds per corner; with quattro four-wheel drive you should keep matching tyres across an axle, which can mean replacing in pairs. Servicing is either a fixed 12-month or 9,300-mile schedule or a variable plan up to 24 months or 18,600 miles, with an oil-service indicatively around £325 and a larger inspection service nearer £565 at a main dealer. Annual road tax (VED) sits at the standard rate, and because every Q8 cost over £40,000 new it also carried the expensive-car supplement until its sixth birthday, so a 2019 car has cleared that but a 2021 car may not have. Insurance is steep: most variants fall in group 48 to 50, the top of the scale.
| Item | Audi Q8 4M (2018-2024) | Source |
|---|---|---|
| 50 TDI engine | 3.0 V6 diesel, 282bhp, 48V mild-hybrid | Parkers Q8 (2018 on) |
| SQ8 engine | 4.0 V8 TDI 429bhp (2019), then 4.0 V8 TFSI 500bhp (2020 on) | Auto Express used Q8 guide |
| Insurance group | 48 to 50 | Parkers insurance groups |
| DVSA recalls | Several; check by registration | DVSA recall check |
The 2023 facelift: what actually changed
The mid-life update reached UK order books for the 2024 model year. The headline changes are HD Matrix LED headlights with a laser high beam and digital daytime running lights, optional digital OLED rear lights with selectable signatures, redesigned front and rear bumpers, a new grille pattern and fresh wheel designs. Inside, the MMI gained built-in apps such as Spotify and Amazon Music. The mechanical line-up barely moved: the 50 TDI diesel and 55 TFSI petrol V6 mild-hybrids carried over, and the SQ8 kept its V8. UK facelift pricing opened around £75,500 for a 50 TDI S line and ran past £116,000 for a loaded SQ8 Vorsprung. For used buyers the practical takeaway is simple: the facelift is a styling and tech refresh, not a reliability reset, so a well-kept pre-facelift 50 TDI at half the price is the smarter spend unless you specifically want the new lights.
Pre-purchase checks and warranty before you pay a deposit
Run these before you hand over a penny on any used Q8.
- Check the full MOT and mileage history free on GOV.UK MOT history, watching for advisories on suspension, brakes and tyres.
- Confirm every recall is closed with the DVSA vehicle recall service, checking every outstanding action against the registration before you buy.
- Test the air suspension cold: the car should sit level after standing overnight and raise and lower without warnings.
- Work through every MMI screen function and the reversing camera, and pair a phone to flush out infotainment faults.
- On a 50 TDI, check AdBlue has been maintained and the service book shows regular longer-distance use, not town-only miles.
- For a dealer car, ask whether Audi Approved Used warranty applies and read the wording on air suspension and electronics cover, or compare an independent plan; our Warranty Direct vs MotorEasy vs ALA comparison shows how aftermarket cover treats big-ticket suspension and electronics claims.
- Budget separately for a fresh set of 21-inch or 22-inch tyres in case the current set is near the limit.
Our take
Our verdict in this Audi Q8 used buyer’s guide is that the car is a genuine bargain for the badge and the cabin, but only bought carefully. The strongest buy is a 2020-or-later 50 TDI in S line trim, on full Audi service history, with a healthy air-suspension test and a clean MMI; from around £30,000 that is a lot of luxury coupe-SUV for the money. The 55 TFSI works for low-mileage town drivers who want petrol refinement. The SQ8 and RS Q8 are wonderful but costly to feed, and the 4.0 V8 was diesel before it was petrol, so always confirm the fuel. Who walks away: anyone tempted by a cheap car with a thin file, an air-suspension warning, or 22-inch tyres on the wire. What flips the decision is the paperwork. A boring, fully stamped, recall-closed 50 TDI beats a flashier car with mystery history every time.
Which used Audi Q8 engine should I buy?
Is the Audi Q8 air suspension expensive to fix?
Was the Audi SQ8 a diesel or a petrol?
How many recalls does the Audi Q8 have?
What does it cost to run an Audi Q8?
Related reading on CDE
- Audi Q7 4M common faults at 60-80k miles
- Audi Q5 FY used buyer’s guide: the 45 TFSI quattro spec to buy
- Audi A7 C8 used buyer’s guide: 45 TDI, 55 TFSI and options to avoid
How we researched this guide
Every pick here is shortlisted from hands-on testing and time spent living with the hardware by the CDE desk, then sanity-checked against current UK pricing, manufacturer specs and real-world performance before it makes the cut. We never rank for commission — affiliate links don't change the order.
Buyer action
Where to check next
Use this as the final check before paying a deposit, signing finance paperwork or relying on a headline monthly figure.
