Forte product questions, answered

This is the front door to every question page on the site. Each one starts from a symptom in your own words, a blue puff on startup, a failed emissions test, a DPF light, a tick from the top of the engine, and answers it in the first two sentences, including when a Forte product will not help. The pages are written by Phil Clements, who sells Forte additives from Lichfield in the UK, tested and photographed the Seal Conditioner on his own seals before he sold a bottle, and hires out the tool that changes N62 valve stem seals without removing the heads. Nothing on them is invented: the product facts come from Forte's own technical documentation, and where that documentation says a product will not fix something, the page says so too. Pick the page that sounds like your car, read the checks before the order button, and message Phil if your case does not fit.

By Phil Clements, BMW Tool RentalUpdated 16 September 2026

How do I use these pages?

Start from the symptom, not the product. The product comes at the end, if it fits.

There are three kinds of page. The symptom pages answer a question the way you would type it into Google: blue smoke when accelerating, failed the MOT on diesel emissions, DPF light and limp mode. Each explains why it happens, gives you a cheap check to do first, lays out what fixes it, states plainly when a Forte product will not, and ends with a visible FAQ built from the questions customers actually ask.

The product question pages take one product, such as Oil Fortifier or Advanced Formula Motor Flush, and answer every question customers have sent about it: dose, timing, compatibility, what it will and will not do.

The comparison pages are for when you already know the category and want to choose well: the best additive for valve seals, the right engine flush for a wet-belt engine, Oil System Protector against Oil Fortifier, or hiring the BMW valve stem seal tool against a workshop bill.

Every page links to the product page it discusses, where the price, the order button and the customer reviews live. Prices are the same everywhere on the site, UK delivery is free on orders of £35 or more, and orders outside the UK show postage and any duty at checkout before you pay. If you read a page and your car still does not fit, use the contact form and describe the symptom; Phil answers those himself and will say if a bottle is the wrong purchase.

Questions about buying from BMW Tool Rental

Do you deliver outside the UK?
Yes. UK delivery is free on orders of £35 or more. Orders to the USA, Canada, Australia, New Zealand, Ireland and the rest of Europe are sent tracked from the UK, with postage and any duty shown at checkout before you pay. There is a dedicated page for US customers.
Is UK delivery really free?
Yes, on Forte orders of £35 or more (up to 2 kg). Under £35, Royal Mail Tracked 48 is £3.65 or Tracked 24 is £4.65, shown at checkout before you pay. The valve stem seal tool hire includes Special Delivery to you; you pay the return postage on the kit.
Who is Phil Clements?
The person behind BMW Tool Rental, based in Lichfield in the UK. He started by hiring out the AGA tool that changes BMW N62 valve stem seals without removing the cylinder heads, tested and photographed Forte Seal Conditioner on his own seals before selling it, and now sells the Forte additive range alongside the tool hire. He writes these pages and answers the messages himself.
How do I ask a question about my own car?
Use the contact form on the site and describe the symptom, the car and any fault codes. Phil reads every message and replies himself, and he will tell you plainly if none of the products is the right fix for your case.
Can I return a product?
Yes. You have 14 calendar days from the day you receive an item to return it, as long as it is unused, in the condition you received it and in its original packaging. Contact Phil first with your order number and he will tell you where to send it. The full returns policy is linked from the footer of every page.
Do the pages tell me when a product will not work?
Yes, on every one, in the first paragraph and again in a dedicated section. The product facts come from Forte's own technical documentation, and where that says a product cannot fix something, such as Seal Conditioner and piston rings or the DPF Cleaner and a filter that is packed solid, the page says so.
Can I hire the BMW valve stem seal tool?
Yes. The AGA tool for changing N62 valve stem seals with the heads and cams in place is £220 for seven days, or £550 with a full Elring seal kit included; Special Delivery to you is included and you pay the return postage. The details and booking are on the homepage.
Are the prices on these pages the same as on the product pages?
Yes. Every price is the live product price in pounds sterling, and the product page carries the order button. If you ever see a difference, the product page is correct; message Phil and he will fix the question page.

Pick the question that sounds like yours

Blue smoke from the exhaust when accelerating or on startup: is it valve stem seals?The five-minute test that separates seals from rings, and the £18 additive that fixes hardened seals.Failed the MOT on diesel emissions: how do I lower them before the retest?What smoke opacity means, what to check first, and the 100 to 200 mile treatment plan.Failed the MOT on petrol emissions: CO, HC and the catalytic converterWhat the three numbers mean and whether a catalytic converter cleaner can get it through.Turbo lag getting worse and P0299: are the variable vanes sticking?How to tell sticking vanes from a boost leak, and the chemical clean that frees them.DPF warning light, P2002 or limp mode: can I clear it without a garage?What blocks a regeneration, the road-and-bottle sequence, and when it is a garage job.Noisy hydraulic lifters or a VVT rattle on startup: what actually fixes it?Flush first, then Top End Treatment. What to check before you add anything.AdBlue warning light and P20EE: what the crystals are and how to clear themCrystals versus a failed part, and the additive that goes in the AdBlue tank.Harsh or slipping automatic gear changes: fluid, additive or gearbox?How to tell tired fluid from a worn box, and what a transmission treatment does.Forte Oil Fortifier: every question customers askOil consumption, dropping oil pressure, dose, the two-step with Seal Conditioner.Forte Advanced Formula Motor Flush: every question customers askHow to flush, what it frees, and why it is not for wet-belt engines.Forte Advanced Formula Petrol Treatment: every question customers askInjectors, inlet valves, rough idle, LSPI, direct injection and hybrids.Forte Diff and Gear Treatment: every question customers askManual gearboxes, differentials and transfer boxes on gear oil.Forte Bio Degreaser and Cooling System Flush: every question customers askCleaning the cooling system before a coolant change or a stop leak.Best additive for valve seals: what works, what doesn't, and what to try firstThe category criteria, honest limits, Forte's two-step, and shipping to the US.Best radiator stop leak for a minor coolant leak: how to chooseFibre versus sealant, OAT compatibility, and what a stop leak will not fix.Best engine flush for a wet-belt engine: 1.0 EcoBoost, 1.2 PureTech, 1.0 TSINew Generation Engine Flush is the wet-belt-safe one. Motor Flush is not.Forte Oil System Protector vs Oil Fortifier: which one does my engine need?Two Forte oil treatments compared by additive profile and by symptom.BMW N62 valve stem seals: tool hire at £220 vs a workshop billWhat the job involves, what the hire includes, and when the garage makes more sense.

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.

Registered office
Clements Trading Ltd
82a James Carter Road
Mildenhall, Bury St Edmunds
Suffolk, IP28 7DE
Lichfield
BMW Tool Rental
63 Purcell Avenue
Lichfield
Staffordshire, WS13 7PH

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.

BMW Tool Rental is an independent specialist supplying tool hire and Forte automotive additives. We are not affiliated with, authorised by, or endorsed by BMW AG. "BMW" is a trademark of BMW AG and is used here for descriptive/compatibility purposes only.

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