Forte Oil Fortifier

Forte Oil Fortifier

High mileage
engine burning
oil?

As engines wear, oil slips past piston rings and valve seals causing consumption, blue smoke and dropping oil pressure. Forte Oil Fortifier is an engine oil thickener that safely raises your oil's viscosity — reducing what's getting past and restoring pressure in worn, high-mileage engines.

Order now — £18.00 → How it works
★★★★★
Free UK delivery · Add to existing oil · Use before Forte Seal Conditioner
Forte Oil Fortifier bottle — reduces oil consumption and restores oil pressure in high mileage worn engines
Does your engine need Forte Oil Fortifier?
🛢️
Going through oil between services
If you're topping up oil more than you used to — especially on a high mileage engine — worn piston rings and valve seals are allowing oil to slip past and burn off. Forte Oil Fortifier reduces the amount getting through.
Forte Oil Fortifier can help
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Blue smoke under load or acceleration
Blue smoke that appears consistently under acceleration — rather than just on startup — often indicates oil burning past worn piston rings rather than valve seals. Oil Fortifier addresses this by thickening the oil.
Forte Oil Fortifier can help
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Low or dropping oil pressure warning
Worn engine clearances allow oil to drain away more easily, reducing oil pressure. Thickening the oil with Forte Oil Fortifier reduces this drain and helps restore pressure throughout the lubrication system.
Forte Oil Fortifier can help
The worn engine problem

Why Do High Mileage Engines Burn Oil and Lose Pressure?

Every engine wears as it accumulates mileage. The clearances between components — piston rings and cylinder walls, valve stems and guides — gradually increase. And as those clearances grow, oil finds its way through.

In a new engine the tolerances are tight — oil film is controlled precisely by the piston rings and valve stem seals. As mileage builds, the metal surfaces wear microscopically and the clearances open up. Oil that should be kept in the sump begins to slip past the rings into the combustion chamber where it burns, or past the valve guides where it burns on the exhaust valves.

The result is increased oil consumption, blue smoke under load and — because oil is draining through enlarged clearances — dropping oil pressure. Standard oil changes can't fix worn clearances. The metal isn't coming back. But you can give the oil less chance of getting through those gaps.

That's what Forte Oil Fortifier does — it thickens the oil to reduce what's slipping past worn components, and restores the oil pressure that worn clearances have been robbing.

Increased clearances drive oil consumption and smoke — showing how worn engine clearances between piston rings and cylinder walls allow oil to bypass into the combustion chamber causing blue smoke and oil consumption
Restoring operational pressure through advanced fluid dynamics — showing how Forte Oil Fortifier's viscosity improvers thicken the engine oil to reduce oil passing worn clearances and restore oil pressure
What it does

What Does Forte Oil Fortifier Do?

Thickens the oil. Forms a protective film on worn surfaces. Restores pressure. It's not a cleaner — it's a restorer. Built specifically for high mileage engines that have moved beyond routine maintenance.
  • ✓
    Safely raises oil viscosity — the right way This is not the same as switching to a thicker oil grade, which can starve a worn engine of flow and cause real damage. Oil Fortifier's advanced viscosity improvers raise the film strength of your existing, correct-grade oil — reducing the amount passing worn piston rings and valve seals, without compromising cold-start flow
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    Forms protective film on worn surfaces Anti-wear agents coat worn metal surfaces — slowing further wear and reducing the metal-to-metal contact that causes noise
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    Restores dropping oil pressure Thicker oil drains less readily through enlarged clearances — rebuilding oil pressure throughout the lubrication system
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    Replenishes depleted viscosity improvers Viscosity improvers in aged oil break down over time — Oil Fortifier replenishes them to maintain oil film integrity between changes
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    No drain required Add to existing engine oil via the filler cap — the engine keeps running while it works
Oil Fortifier vs Oil System Protector — what's the difference?

Which Forte Oil Product Is Right for Your Engine?

They look similar but they do different jobs. Oil Fortifier is built for worn engines that need restoring. Oil System Protector is built for healthy engines that need protecting. The additive profiles tell the story.

Forte Oil Fortifier has the highest viscosity improver rating of any Forte oil product — 5 out of 5. That's what makes it specifically for worn high mileage engines. It prioritises thickness and pressure restoration over cleaning.

Forte Oil System Protector has a balanced profile — 4 out of 5 across detergents, dispersants and anti-wear, with no viscosity improvers at all. It's designed to keep a healthy engine clean and protected, not to address the worn clearance problem that Oil Fortifier tackles.

High mileage engine burning oil or losing pressure? → Forte Oil Fortifier. Healthy engine, want to maintain it? → Forte Oil System Protector.

Targeted additive profile for mechanical restoration — showing the Forte Oil Fortifier additive profile with viscosity improvers 5 out of 5 the highest of any Forte oil product compared with Forte Oil System Protector designed for healthy engines
Viscosity Improvers
5/5
Highest of any Forte oil product — the primary function of Oil Fortifier
Anti-Wear Agents
4/5
Forms protective film on worn metal surfaces — slows further wear
Detergents
2/5
This is a restoration product not a cleaner — use Forte Engine Flush for cleaning first
Dispersants
2/5
Basic dispersant package to keep wear particles in suspension
Real world result

BMW 750 5.0L — 1 Litre Every 300 Miles. Fixed.

88,000 miles. Burning 1 litre of oil every 300-400 miles. Blue smoke. The kind of consumption that makes you think the engine is done. It wasn't.

The diagnosis was suspected bore lacquering and sticking piston rings — the rings weren't worn out, they were gummed up and not sealing correctly. The fix was systematic.

  • 1
    First Forte Engine Flush treatment Added to the existing oil and driven for 500 miles — beginning to dissolve the bore lacquering and free the stuck rings
  • 2
    Oil change — second Forte Engine Flush treatment Fresh oil, second Engine Flush, driven another 500 miles — continuing the cleaning process
  • 3
    Oil change — 2 bottles of Forte Oil Fortifier added Fresh oil with 2 bottles of Oil Fortifier for this large capacity V8 — thickening the oil around the now-freed rings
  • 4
    After 1,500 miles Smoking stopped completely. No oil being used at all. The combination of cleaning and then fortifying the oil resolved a level of consumption most people would have used as justification to scrap the engine.
Real world telemetry BMW 750 5.0L — showing the case study of a BMW 750 with 88000 miles burning 1 litre of oil every 300-400 miles resolved by two Forte Engine Flush treatments followed by two bottles of Forte Oil Fortifier resulting in smoking stopping completely after 1500 miles
Diagnostic codes

What Fault Codes Are Linked
to Low Oil Pressure?

As engines wear, clearances open up and oil drains through them too easily — pressure drops and the ECU logs it. By raising the oil's film strength, Forte Oil Fortifier helps a worn engine hold pressure again. If you're seeing these alongside high oil consumption or a noisy top end, worn clearances are the likely cause.

  • P0520
    P0521
    P0522
    Engine Oil Pressure Sensor / Low Oil Pressure The core oil-pressure codes — sensor circuit faults, range/performance, or genuinely low pressure. On a high-mileage engine with widened clearances, a thicker oil film helps rebuild pressure and steady the reading. Always rule out a failed sensor or pump first. Secondary code.
  • P0524
    Engine Oil Pressure Too Low The ECU has detected oil pressure below the safe threshold — often a warning sign on a worn, high-mileage engine. Oil Fortifier's viscosity improvers help restore the oil film and pressure, but persistent low pressure must be investigated mechanically. Secondary code.
  • P0011
    P0014
    Camshaft Timing Over-Advanced (VVT / VANOS) Variable valve timing needs stable oil pressure to work. When pressure drops on a worn engine, the cam phasers can't hold position and these codes appear. Restoring oil pressure supports correct VVT operation. Secondary code.

Important: Oil Fortifier helps a worn engine hold pressure — it is not a fix for a failed oil pump or sensor. If a pressure code persists after treatment, get it diagnosed. Ask Phil if you're unsure.

Diagnostic treatment routing and application protocol — showing when to use Forte Oil Fortifier and the correct sequence including using Forte Engine Flush first and adding Oil Fortifier before Forte Seal Conditioner if treating valve seals
Instructions

How Do I Use Forte Oil Fortifier?

Add to existing engine oil via the filler cap — no drain needed. But the order matters, especially if you're also treating valve seals.
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    For oil consumption and pressure — use after Engine Flush Use Forte Engine Flush first to clean the engine — then add fresh oil with Forte Oil Fortifier. A clean engine gives Oil Fortifier the best possible environment.
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    Also treating valve seals? Add Oil Fortifier first Add Oil Fortifier, drive one day, then add Forte Seal Conditioner. The thicker oil environment gives the seal conditioner the best chance of working.
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    Large displacement engines — use two bottles For V8 and larger engines over 4.0 litres use two bottles for the correct concentration in the larger oil volume.
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    Stays in until the next oil change No need to drain — Forte Oil Fortifier remains active in the oil until the next service.
Common questions

Questions people ask
before they order.

Is this the same as just using a thicker oil?
No — and this is an important difference. Switching to a thicker oil grade (say 10w-40 instead of the 5w-30 your engine is designed for) can starve a tight engine of flow on cold starts and actually cause damage. Forte Oil Fortifier instead raises the viscosity and film strength of your existing, correct-grade oil in a controlled way — so you get the benefit of a stronger oil film over worn clearances without the risks of running the wrong grade.
Is it bad to drive a car that's burning oil?
It's risky to ignore. If the oil level drops too low between top-ups you risk oil starvation and serious engine damage, and the blue smoke can fail an MOT and clog the catalytic converter or DPF. Topping up buys time, but treating the cause — restoring the oil film over worn rings and seals with Forte Oil Fortifier — is the cheaper long-term fix. If the level is dropping fast or the oil pressure light shows, stop and investigate before driving on.
My engine uses a quart every 1,000 miles — is that too much for Oil Fortifier to help?
Not necessarily. The BMW 750 case study above was burning 1 litre every 300-400 miles — significantly worse than that — and resolved completely. The key question is whether the consumption is caused by worn clearances (which Oil Fortifier addresses) or physically damaged components. If the engine otherwise runs well, it's worth trying before writing it off.
Should I drain the oil first before adding it?
No — add to existing oil. However if the oil is very old or overdue a change, use Forte Engine Flush before the oil change to clean the system, then add Oil Fortifier to the fresh oil. Clean oil gives Oil Fortifier a much better environment to work in.
Can I use it with fully synthetic oil?
Yes — Forte Oil Fortifier is compatible with conventional, semi-synthetic and fully synthetic engine oils. It works through whatever oil is currently in the engine.
I'm also using Forte Seal Conditioner — which goes in first?
Oil Fortifier goes in first. Add it to the existing oil and drive normally for one day. Then add Forte Seal Conditioner. The thicker oil environment that Oil Fortifier creates gives Seal Conditioner the best possible chance of reaching and restoring the valve stem seals.
My oil pressure warning light is coming on — will this fix it?
If the low oil pressure is caused by worn engine clearances allowing oil to drain too readily — which is common on high mileage engines — Forte Oil Fortifier can restore it by thickening the oil. If the oil pressure warning is caused by a failed oil pump, a blocked oil pick-up or very low oil level, those need addressing first. Check the oil level and top up before adding anything.
Is it the same as Forte Oil System Protector?
No — they're designed for different situations. Oil Fortifier has the highest viscosity improver rating of any Forte oil product and is specifically for worn high mileage engines needing restoration. Forte Oil System Protector has a balanced maintenance profile for healthy engines. If you're burning oil, Oil Fortifier. If you want to maintain a healthy engine, Oil System Protector.

Stop the oil
burning.
Restore the pressure.

Forte Oil Fortifier — highest viscosity improver rating of any Forte oil product. Add to existing oil, no drain required. Free UK delivery.

£18.00

Order Forte Oil Fortifier — £18.00 →
Use as part of this protocol
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    Forte Engine Flush Use first — clean the engine before adding Oil Fortifier. For bore lacquering or sticking rings use twice with 500 miles between treatments as in the BMW 750 case study.
  • →
    Forte Seal Conditioner If also treating valve stem seals — add Oil Fortifier first, drive one day, then add Forte Seal Conditioner. The two products work together.
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    Forte Top End Treatment If also experiencing noisy valve lifters or VVT issues alongside oil consumption — Forte Top End Treatment targets the upper valve train.
Complete oil system care

Use alongside these products.

Always use first
Forte Engine Flush
Clean before you fortify. Forte Engine Flush removes the bore lacquering and sludge that causes oil consumption before Oil Fortifier goes in — giving it a clean system to work in. For stuck piston rings use twice with 500 miles between treatments.
View Forte Engine Flush →
If also treating valve seals
Forte Seal Conditioner
Add Oil Fortifier first, drive one day, then add Forte Seal Conditioner. The thicker oil created by Oil Fortifier gives Seal Conditioner the best possible environment to reach and restore the valve stem seals. The two products are designed to work together.
View Forte Seal Conditioner →
For noisy valve lifters too
Forte Top End Treatment
High mileage engines often have noisy valve lifters or sticking VVT alongside oil consumption. Forte Top End Treatment has the highest detergent rating of any Forte oil product and targets the upper valve train specifically.
View Forte Top End Treatment →
Worn piston ring symptoms

Worn Piston Rings Symptoms: Smoke, Oil Use and Pressure Clues

Piston rings control the oil film on the cylinder wall. When they wear, stick, or stop sealing properly, oil can pass into the combustion chamber and burn with the fuel.

The source-backed signs are car burning oil between services, blue exhaust smoke, high oil consumption, and a level on the dipstick that keeps dropping. On a high mileage engine burning oil, those symptoms are consistent with oil escaping past worn piston rings or valve stem seals and burning in the combustion chamber.

Blue exhaust smoke is worth treating as an oil-control warning rather than just a nuisance. Left unchecked, oil burning fouls spark plugs, can clog a catalytic converter, and is a common cause of an MOT emissions or visible-smoke failure — all far more costly than addressing the oil film early. Forte Oil Fortifier is aimed at the worn-clearance side of that problem: it strengthens the oil film and reduces the amount of oil passing worn internal clearances.

  • Oil useFrequent top-ups between services, especially with no external leak, are a classic high oil consumption warning.
  • Blue smokeBlue smoke is a source-backed sign that oil is escaping past worn piston rings or valve stem seals and being burnt.
  • Hot pressureWorn internal clearances can show as dropping oil pressure when hot because warm oil flows through the gaps more easily.
  • LimitsOil Fortifier is a lubrication and viscosity treatment, not a mechanical repair. Severe or persistent oil loss still needs diagnosis.

Where Forte Oil Fortifier fits

Forte Oil Fortifier is an engine burning oil additive for worn, high-mileage engines. Its advanced viscosity improvers strengthen the oil film and reduce the amount of oil passing worn piston rings, valve stem seals and enlarged bearing clearances.

For best results, clean the system first with Forte Advanced Formula Motor Flush, change the oil, then add Oil Fortifier to the fresh oil. If treating valve stem seals as well, add Oil Fortifier before Forte Seal Conditioner.

Hot idle oil pressure

Low Oil Pressure at Idle When Hot: Why the Oil Light Flickers

Low oil pressure at idle when hot is one of the ways worn internal clearances can show up. As the oil warms, it can pass through worn clearances more easily, so a high mileage engine may show dropping oil pressure when warm.

Ignoring a genuine low-pressure warning is the expensive path: starved bearings and journals wear rapidly, and the end of that road is a spun bearing or seized engine — an engine rebuild or replacement rather than a bottle of treatment. If the dashboard oil warning appears alongside high oil consumption or other signs of a worn engine, do not ignore it. Forte Oil Fortifier can help where the pressure loss is wear-related because it safely thickens the existing correct-grade oil and helps the engine hold a stronger oil film when warm.

  • 1
    Check the oil level firstOil Fortifier is added to the existing engine oil, so confirm the oil level is correct before adding any treatment.
  • 2
    Do not ignore a constant warning lightOil Fortifier is not a mechanical repair. Persistent pressure warnings still need diagnosis rather than more additive.
  • 3
    Use it for wear-related pressure dropWhen the engine otherwise runs normally but oil pressure drops when warm, the product is aimed at rebuilding film strength and reducing drain through worn clearances.
Oil pressure & VANOS fault codes

P0520, P0521, P0522, P0524, P0011 and P0014 Explained

Oil-related fault codes split into two camps: ones that point at the sensor or its wiring, and ones that report genuinely low oil pressure or oil-starved valve timing. Only the second camp is wear-related — and only that camp is something an oil treatment can realistically help.

The first three — P0520, P0521 and P0522 — are oil pressure sensor and circuit codes. The engine management module is unhappy with the signal coming from the oil pressure sensor itself, not necessarily with the oil. These are electrical faults: a failed sensor, a broken or shorted wire, or a poor connection. They need a wiring and sensor diagnosis, and usually a new sensor — no additive will clear them.

P0524 is different: it reports that engine oil pressure is genuinely too low. On a worn, high-mileage engine that can be a wear-related pressure loss, which is exactly the situation Oil Fortifier is designed for — though a failed oil pump or blocked pickup is a mechanical job, so a real low-pressure code is always worth a proper check first.

P0011 and P0014 are camshaft timing over-advanced codes (intake and exhaust cam, Bank 1). The variable valve timing / VANOS system is actuated by engine oil pressure, so low, dirty or wrong-viscosity oil is one of the most common triggers on a worn engine — clean, correct-grade oil with Oil Fortifier can help there. But the same codes can come from a failed VANOS solenoid, a worn actuator or a stretched timing chain, and those are mechanical repairs that no additive will fix.

The cheap pathA proper diagnosis, fresh correct-grade oil and Oil Fortifier — when the cause is wear or oil condition. Pence in the pound against the alternative.
The cost of ignoring itSustained low oil pressure or mis-timed valves accelerate bearing, cam and timing wear — and run on into timing-chain, head or full-engine damage.
  • P0520Engine Oil Pressure Sensor/Switch Circuit — an out-of-range signal pointing at a sensor or wiring fault, not the oil.
  • P0521Sensor/Switch Range/Performance — the signal is present but irrational or stuck; again a sensor-side fault.
  • P0522Sensor/Switch Low Voltage — circuit voltage too low (often a short to ground), read by the module as low pressure.
  • P0524Engine Oil Pressure Too Low — a genuinely low reading; on a worn engine this can be wear-related and is where film strength matters.
  • P0011"A" (intake) Camshaft Timing Over-Advanced, Bank 1 — VANOS/VVT timing off, commonly oil-pressure or oil-condition related.
  • P0014"B" (exhaust) Camshaft Timing Over-Advanced, Bank 1 — the same oil-actuated timing system on the exhaust cam.

Will Forte Oil Fortifier clear a P0520, P0521 or P0522 oil pressure code?

Usually not. P0520, P0521 and P0522 are sensor and circuit codes — they point at the oil pressure sensor or its wiring rather than the oil itself, so they need an electrical diagnosis and often a new sensor. Oil Fortifier only addresses pressure that is low because of wear, such as a P0524 "oil pressure too low" reading on a high-mileage engine, where strengthening the oil film can help.

Can an oil additive fix a P0011 or P0014 VANOS / camshaft timing code?

Only when the cause is oil-related. The VANOS / variable valve timing system is actuated by engine oil pressure, so low, dirty or wrong-viscosity oil is a common trigger for P0011 and P0014 on worn engines — and clean, correct-grade oil with Forte Oil Fortifier can help there. If the code is caused by a failed VANOS solenoid, a faulty actuator or a stretched timing chain, that is a mechanical repair and no additive will fix it.

Take A Look At Our 5 Star Reviews For Forte Seal Conditioner

At BMW Tool Rental, we pride ourselves on providing excellent customer service and offering honest and reliable advice to our customers. We understand that when it comes to your car, you want to ensure that you are using the right products and getting the right advice. That's why we take the time to listen to our customers, understand their concerns, and provide the best possible solution.

Our forte seal conditioner has received numerous 5-star reviews from our satisfied customers, who have found our product to be effective in reducing engine oil leaks and stopping blue smoke caused by worn valve seals. However, we don't just rely on product reviews to show our commitment to customer satisfaction. We offer a personal touch that sets us apart from other retailers.

If you have any questions about our products or services, we encourage you to reach out to us. We're always happy to help and provide you with the information you need to make the right decision. Whether you're looking to rent our AGA valve seal tool or purchase our forte seal conditioner, we're here to help.

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Clements Trading Ltd trading as BMW Tool Rental. Registered in England & Wales, company no. 10629836. Registered office: 82a James Carter Road, Mildenhall, Bury St Edmunds, Suffolk, IP28 7DE.

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