Mileage Blockers vs Mileage Correction
Mileage Blockers vs Mileage Correction
When it comes to vehicle mileage management, it’s important to understand the difference between mileage blockers and mileage correction. Mileage blockers are devices used to pause the odometer temporarily, usually during dyno testing, track days, or off-road events, ensuring that extra miles aren’t recorded in the vehicle’s ECU. This maintains accurate performance data without altering the vehicle’s actual mileage permanently.
On the other hand, mileage correction involves permanently adjusting the odometer reading to reflect a different mileage. Unlike blockers, this process changes the logged distance on the vehicle, which can affect resale value, service schedules, and legality. Mileage correction should only be performed by qualified professionals and must comply with UK road laws, whereas mileage blockers are for off-road or testing use only and do not alter the true odometer reading.
At our Slough-based workshop, we specialise in installing mileage blockers for a wide range of performance and luxury vehicles, including Ferrari, Lamborghini, Porsche, McLaren, BMW M, Audi RS, Mercedes-AMG, Jaguar, Range Rover, and Bentley. Our expert team ensures safe installation and provides guidance on proper off-road or dyno use, giving you precise performance data without impacting your vehicle’s recorded mileage.
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EXCELLENT Based on 318 reviews Rahul DollTrustindex verifies that the original source of the review is Google. Onyx carried out a Major service to my BMW 125i, process was quick and easy. No upsells and was transparent about everything. I’m only rating this 4/5 as it would be useful to know the exact oil / parts used in the service and for this to be reflected in the invoice. Hopefully be able to come back and get a Stage 1 map soon - cheers Anil SoniTrustindex verifies that the original source of the review is Google. Thank you guys for your professional, dedicated and honest opinion. You made my day by fixing my son's car so he could use it for DoE at very short notice. Max and Kay were brilliant and I would definitely recommend this garage as a organised and trustworthy business. Keep up the good work. subin pradhanTrustindex verifies that the original source of the review is Google. Took my BMW 440i to install downpipe and mid pipe. Top guys with good service and reasonable price. Will be going back for more work done. J JareCkiTrustindex verifies that the original source of the review is Google. I just done Stage1 in my audi s3, car drive superb, excelent service, thanks Ben,Sam and Onyx team! Brilliant work Dan MayTrustindex verifies that the original source of the review is Google. Honest and knowledgable! Rare these days - saves me hundreds by checking my Golf R properly. Will only use these guys from now on Darren DawesTrustindex verifies that the original source of the review is Google. I took my jaguar xfr to these guys for a re map . Excellent service. They could not have been more helpful. Very knowledgeable they definitely know what they are doing. If your looking for a re map I would highly recommend you speak to them. HanaTrustindex verifies that the original source of the review is Google. I was recommended Onyx to get my diamond-cut alloys refurbished. I am located an hour away but the recommendation was important so decided to leave my car with these guys. First impressions, the team were very polite, friendly (Essan, Ben and the guys that actually did the refurb in the intense heat) The prices were competitive. And the quality of work was super. There was slight miscommunication post the sale (which happens) but I was pleased they resolved this to my satisfaction. One idea I would suggest is advising the customer 'before' the work starts that the TPF valves may need replacing so we have the option to decide whether to do it whilst the wheels are off anyway rather than post refurb to avoid scratching the newly done alloys. Otherwise happy with my overall experience. MarkTrustindex verifies that the original source of the review is Google. Amazing service pavan khanguraTrustindex verifies that the original source of the review is Google. The best experience ever well organised clean friendly team and the experience was amazing A big up to the whole staff. N EILTrustindex verifies that the original source of the review is Google. Onyx do the job well and they're nice guys, but the experience is disappointing. We're car guys. We want to understand more about our cars and experience what's going on. At Onyx, you arrive and get ushered to the Waiting Room, which is a small box room with no windows, no toilet and no refreshments. 2 hours later someone comes in and tells you your car is all done. Such an opportunity missed! Places like Center Gravity let you watch, chat to the mechanic, looks at your car from underneath while it's on the ramp....and you can have a coffee and use the loo. The nearest loo to Onyx is the pub half a mile away, which isn't open in the mornings. Oh and when you get your bill it's debit card only so make sure you have cash in your current account! With a few changes, Onyx could make it a great experience and have loads more customers!
Install a Mileage Blocker in Slough Today
Protect your vehicle’s value and ensure accurate dyno results with our professional mileage blocker installation service. Our team provides brand-specific guidance, fully tailored to performance and luxury cars, and support for safe off-road or track usage.
Why Choose Onyx Performance for Servicing?
Experts in Performance Cars
Correct Service Schedules
Quality or OEM Parts
Full Vehicle Inspection
Honest Advice, No Surprises
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Frequently Asked Questions
There are no guarantees. These devices are sold for off-road and testing purposes only. Use on public roads may carry risks.
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