Quick Answer
Putting the wrong oil in a modern luxury engine is like filling a Formula 1 car with cooking oil. Viscosity, additive package, manufacturer approval, and base oil type all matter — and the w
"Just put 5W-30 in it."
That sentence has caused more engine damage than most people realise. Because not all 5W-30 is the same. And the oil that's perfect for a Toyota Camry will slowly destroy a Porsche flat-six.
The assumption: Oil is oil. 5W-30 from Brand A is the same as 5W-30 from Brand B. Just match the viscosity number on the cap.
The reality: The viscosity grade (5W-30, 0W-40, etc.) is one of SIX critical specifications. Getting the viscosity right but the other five wrong is like getting the right shoe size but the wrong foot.
The number everyone looks at: 0W-20, 5W-30, 0W-40, 10W-60, etc.
What the numbers mean:
Dubai relevance: The cold-flow number (0W vs 5W) matters less in Dubai because cold starts rarely go below 15°C. The hot viscosity (30, 40, 60) matters MORE because operating temperatures run higher.
This is the critical specification. Every manufacturer has specific oil approval codes:
| Manufacturer | Approval Code | Meaning | |-------------|---------------|---------| | Porsche | C30 (formerly A40) | Specifically formulated for Porsche flat-six and V8 engines | | Mercedes-Benz | MB 229.5 / 229.71 | Specific additive and performance requirements for Mercedes engines | | BMW | LL-01 / LL-04 | BMW Longlife approval. LL-04 also meets diesel particulate filter requirements | | VW/Audi/Bentley/Lamborghini | VW 504.00 / 507.00 | VAG Group specification. 507.00 includes DPF compatibility | | Ferrari | Shell Helix Ultra (exclusive supply) | Ferrari specifies Shell as the approved oil supplier | | Rolls-Royce | BMW LL-01 | Uses BMW specification (shared platform) | | Aston Martin | Castrol EDGE (exclusive supply) | Factory-fill and recommended by manufacturer | | Land Rover | STJLR.03.5003 | Jaguar Land Rover specification |
Why this matters: A Mobil 1 0W-40 that meets Porsche C30 has passed Porsche's own engine tests (300+ hours of operation, specific wear measurements, oil degradation analysis). A generic 0W-40 that does NOT carry this approval has not been tested and may cause accelerated wear.
| Type | Description | Cost | Suitability | |------|-------------|------|-------------| | Group I-III (Mineral/Conventional) | Refined from crude oil | AED 80-150/5L | Older, simpler engines | | Group III+ (Synthetic Technology) | Highly refined mineral base marketed as "synthetic" | AED 150-250/5L | Some modern engines | | Group IV (PAO — True Synthetic) | Polyalphaolefin — chemically synthesised | AED 250-400/5L | High-performance engines | | Group V (Ester — Premium Synthetic) | Ester-based with superior film strength | AED 400-600/5L | Supercars, track use, extreme conditions |
Every luxury car manufactured after 2010 requires Group IV or V synthetic oil. Using Group III (even if labelled "synthetic") in a Porsche or Ferrari voids the specification and may cause premature wear.
Two international classification systems define the additive performance:
ACEA (European — relevant to luxury cars):
API (American — less relevant but commonly seen):
Why this matters in Dubai: Low-SAPS oils (ACEA C3, C5) are mandatory for vehicles with diesel particulate filters. Using a non-low-SAPS oil in a DPF-equipped vehicle will clog the filter — leading to AED 5,000-15,000 DPF replacement.
Modern luxury cars have oil life monitoring systems that adjust the change interval based on driving conditions:
| Driving Pattern | Effect on Oil Life | Adjusted Interval (Dubai) | |----------------|-------------------|--------------------------| | Highway cruising | Gentle on oil — extended life | 12,000-15,000 km | | City traffic, stop-start | Harsh — fuel dilution, short trips don't reach temperature | 8,000-10,000 km | | Spirited driving, track days | Very harsh — high temperature, high shear | 5,000-7,000 km | | Extreme summer traffic | Worst case — sustained high temp, stop-start | 7,000-10,000 km |
Dubai adjustment: Regardless of what the car's computer says, Dubai conditions (sustained heat, traffic, dust) degrade oil 20-30% faster than European conditions. If the car says 15,000 km, change at 10,000-12,000 km.
The oil filter is half the system. A cheap filter with premium oil defeats the purpose:
Rule: Always use an OEM or OEM-equivalent filter. The AED 30 savings on a generic filter isn't worth the reduced filtration quality.
Fast oil change shops use bulk oil — typically one or two specifications to cover "most" vehicles. They match the viscosity grade but often ignore manufacturer approvals.
Scenario: Your Porsche Cayenne needs 0W-40 meeting Porsche C30 (typically Mobil 1 0W-40 FS or Motul 8100 X-cess). The quick lube shop uses their house-brand 0W-40 that meets API SP and ACEA A3/B4 — but does NOT carry Porsche C30 approval.
Result: The viscosity is correct. The base classification is acceptable. But the specific additive formulation and testing that Porsche requires has not been validated. Over time, wear patterns may differ from Porsche's engineering expectations.
Our recommendation: Have your oil changed at a specialist who uses the correct manufacturer-approved oil. The cost difference is AED 100-300 per oil change — trivial compared to engine work.
Q: Can I mix different brands of oil if they have the same specification?
A: Yes — oils that carry the same manufacturer approval (e.g., both meeting Porsche C30) are compatible and can be mixed. The approval process ensures compatibility. However, topping up with a different viscosity (e.g., adding 5W-30 to a system using 0W-40) changes the overall viscosity profile and should be a temporary measure only.
Q: Is more expensive oil always better?
A: Not necessarily — but for luxury vehicles, the correct oil is typically in the AED 250-500 range per 5L. The most expensive oils (AED 600+) are designed for track use or extreme conditions that most road cars don't encounter. The key is matching the specification, not the price.
Q: Does synthetic oil cause leaks in older cars?
A: This was true 30+ years ago when early synthetic oils used ester-based formulations that swelled certain rubber seals. Modern Group IV (PAO) synthetics are compatible with all modern seal materials. If your classic car (pre-1990) hasn't previously used synthetic, consult a specialist — but any car built after 1995 can safely use synthetic.
Q: How do I know if the garage used the correct oil?
A: Ask to see the oil bottle before the change. Check for your manufacturer's approval code on the label. A reputable specialist will show you the product and can provide documentation. If they can't tell you which oil they used, that's a red flag.
Q: Should I use a thicker oil in summer for extra protection?
A: Only if the manufacturer specifies a summer-grade option. Some Porsche models allow both 0W-40 and 5W-50 depending on conditions. But switching to a thicker oil outside the manufacturer's specification (e.g., using 10W-60 in an engine designed for 0W-40) changes the oil flow characteristics and can cause starvation at cold start. Follow the manufacturer's guidance.
You wouldn't accept a random blood transfusion. Don't accept a random oil change. The specification exists for a reason — and in a AED 500,000+ engine, the reason is expensive.
Equipment. Knowledge. Patience. And the correct oil specification printed on the service sheet.
No Fix, No Fee.
Reviewed by [Lubrication Specialist], MotorMec Dubai. Last updated: February 2026
