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TMC Autoflash Gearbox Tuning for GMC Sierra 6.6 V8 D Duramax 403 PS (200004520)
Gear Shift Performance
Make & Model: GMC Sierra
Engine Spec: 6.6 V8 D Duramax
Overview of the tool and installation guide
The all-new TCU Tool is a fully reworked and reprogrammed new plug n play OBD tool that not only unlocks manufacturer’s transmission settings within the vehicles control modules to give better gear shifts, increased performance and release torque. It now also provides adaptation reset as standard helping you get the most from your vehicle, which provides an essential component in your vehicles modifications and upgrade path.
The new updated TCU Tool was developed with three advanced functional requirements.
- The need to improve and optimize the gear shift speeds and modify torque settings in the modern automatic gearing systems to improve the overall driving experience
- The need to create a simple to use Plug n Play OBD solution which is easy to install and at an affordable price
- Provide the end user with a tool that allows the vehicles adaptation settings to be reset to factory, simply and efficiently
How does it work?
The all-new TCU Flash Tool integrates with the vehicles onboard communications network via OBD to access the ECU, TCU and Convenience modules to adjust/reset the shift strategies within the OEM (Original Equipment Manufacturer) control components to "point" or “re address” these strategies to the best and most optimal settings.
This includes changing the transmission shift speed pointer to a faster/different setting. The internal components that make up the mechanics of the transmission have a wide range of tolerance and multiple settings allowing manufacturers in most cases to use single components across a whole range of vehicles, from a VW golf to a Lamborghini Aventador. They all contain similar if not the same generation components, usually built in the same factory, but have model specific programs that are used for their specific application.
The New TCU provides a Clean Start Point
Over time your vehicle may of adapted to a slower shift due to a previous owner or the way the vehicle has been driven over time. Unique to the new 2016 TCU Tool we have now added the extra function of resetting this to provide a Clean slate install. This is an essential step when modifying or tuning as it gives the user a factory clean reference point and base line. This is the first time we have added this feature to our new line of TCU products!
What's all the Torque About?
Torque Limits are also set in various systems and control modules within the vehicle; this is set by the manufacturer and is one of the easy ways to electronically limit power in certain models of vehicles. This allows the manufacturer to release many different power variants with different driving characteristics with only a single engine. This is a much more cost effective way of creating a vehicle range without the need to manufacture multiple engines at different power levels. We all know how many power variants are available for the VW Golf 2.0TDi. Same engine different software settings.
TMC Motorsport ship worldwide on any of our products using DHL, Royal Mail postal service and Parcelforce/GLS. Due to the size and weight of some of our products and the different shipping tariffs to different countries we may need you to contact us with some basic address information to allow us to give you an accurrate shipping quote.
Unless DHL Express is specifically selected tuning kits are shipped with Royal Mail, we do not issue tracking numbers however parcels do carry a basic tracking code for insurance purposes in case they get lost, this tracking code will not give detailed tracking information and is only used in the event of a claim for a missing package, packages are not considered missing unless undelivered in 30 days, Royal Mail will not investigate a missing package until 30 days from shipping date have passed.
If you select the DHL Express shipping option you will automatically receive a tracking code from DHL and can track your package at every stage.
All larger items such as exhausts, alloy wheels, brakes, suspension, seats etc. are shipped with DHL and you will receive a DHL tracking code automatically by email to track your parcel at every stage.
Refund & Returns Policy
ReturnsOur policy lasts 14 days from the date of delivery. If 14 days have gone by since your delivery, unfortunately we can’t offer you a refund or exchange if the item is not faulty. To be eligible for a return, your item must be unused and in the same condition that you received it. It must also be in the original packaging. Several types of goods are exempt from being returned. Any consumable items, including fluids, fragrances,oils that have been opened cannot be returned.
*Special order items can also not be returned, you will be contacted if you have ordered a special order item and made aware of this.
The TMC Motorsport Autoflash Gearbox Tune is excluded from our returns policy as this is a bespoke/ single use/single vehicle product that connects to and is locked to the individual vehicles ECU and cannot be removed by the end user/customer.
Tuning Box & Powerpedal Products can be returned within 14 Days from the date of delivery. Please note if you want to return a correctly supplied Tuning Box or Powerpedal, a fee of £30 +VAT (VAT Applicable to UK & Europe) will be applied to your refund.
To complete your return, you must first email us to confirm your return. Once confirmed we will send you a return form which we require to be filled out and returned inside the package. PLEASE NOTE if this return form is not included with your return package, you will incur an additional charge of £20 +VAT. We also require a receipt or proof of purchase. Please do not send your purchase back to the MANUFACTURER. There are certain situations where partial refunds may be granted: - Any item not in its original condition, is damaged or missing parts for reasons not due to our error. - Any item that is returned more than 14 days after delivery.
This is not guaranteed. Refunds (if applicable) Once your return is received and inspected, we will send you an email to notify you that we have received your returned item. We will also notify you of the approval or rejection of your refund. If you are approved, then your refund will be processed, and a credit will automatically be applied to your credit card or original method of payment, usually within 3-5 business days depedant on your bank. Late or missing refunds (if applicable) If you haven’t received a refund yet, first check your bank account again. Then contact your credit card company, it may take some time before your refund is officially posted. Next contact your bank. There is often some processing time before a refund is posted. If you’ve done all of this and you still have not received your refund yet, please contact us at firstname.lastname@example.org Exchanges (if applicable) We only replace items if they are defective or damaged. If you need to exchange it for the same item, send us an email at email@example.com Shipping To return your product, you should mail your product to: TMC Motorsport, Unit 8, 766 Upper Newtownards Road, BT16 1TQ, Northern Ireland, UK. You will be responsible for paying for your own shipping costs for returning your item if you have recevied the correctly supplied product. Shipping costs are non-refundable. If you receive a refund, the cost of return shipping will be deducted from your refund. Depending on where you live, the time it may take for your exchanged product to reach you may vary. If you are shipping an item over £30, you should consider using a trackable shipping service or purchasing shipping insurance. We cannot guarantee that we will receive your returned item if it is not tracked.
Frequently Asked Questions
Why do you charge TAX (VAT) on your products & shipping?
By law you pay VAT on everything within the UK & Europe e.g. you pay for a Coca-Cola in a shop > VAT is already included in the price. Once a business is VAT Registered they must charge VAT on all products and or services e.g. Shipping as its classed as a service. VAT is collected for the government by us then we must pay it to them. This is the law. We cannot waiver VAT as its not a choice & is classed as tax evasion.
Why do you show Incl VAT Prices & Excl VAT Prices?
We show both prices as we ship worldwide. Outside of the EU VAT is not applied however once the product lands you pay your countries own TAX in the way of import duty instead which varies dependant on your countries laws.
I have VAT Number, Can I purchase without VAT?
Yes we can offer VAT free sales outside of the UK once we have your VAT number. Please note the VAT number must be sent to us and checked before we can issue a VAT free invoice, the address in which we deliver must be the same as registered under the VAT number. We are not allowed to deliver to another address other than the address registered to the VAT number. Within the UK, it is known that if you have a VAT number you must purchase as normal then use your VAT Invoice (Supplied by us) to claim back your VAT.
Products shipped via DHL Express will automatically send out an email upon collection of your order with the email address you provided. Items with shipping cost under £8 to the UK will be shipped via the Royal Mail Recorded. These tracking numbers are sent from our firstname.lastname@example.org address at the end of each working day.
If you wish to confirm if this item is suitable for your vehicle could you please contact us via our contact methods including your vehicle chassis number in your message.
Please refer to our return & refund policy here > %%GLOBAL_ShopPathSSL%%/shipping-returns/
Please see the item title or description.
The time of delivery depends on the product purchased & the service used. We normally use DHL Express for most items which is next day to many countries however often Royal Mail may be used. Some items also are drop shipped from other warehouses of ours around the world. These warehouses may also use different couriers from normal such as UK Mail. Delivery times with Royal Mail or UK Mail are usually 1-3 Days to UK / 3-7 Days for Mainland Europe / 7-14 Days for Worldwide Shipments. Please note that sometimes deliveries can be faster or slower than the times indicated depending on the circumstances.
We can offer this service but please contact us prior to calling to ensure the product is in stock and ready for collection.
Postage is calculated on a per item basis. Please look at the item and postage prices will be indicated e.g. UK, Mainland Europe & Worldwide. Please note that sometimes some locations may be “classed” as a remote area & you will be contacted regarding this as an extra charge may need to be paid. For example, the Scottish Highlands – An extra charge is applied by DHL.
We ship worldwide. If your unsure if we ship to your country, please contact us via our contact methods.
Yes, if you are making multiple purchased then please add your items to the cart continue to checkout & you will find a “Combined Shipping Quote” Option. Please follow the instructions to apply for a combined quote. Once you receive your quote back from us, you may proceed with your order & the difference will be refunded upon the transaction being processed.
PayPal is the preferred payment method for all purchases however we also accept Credit & Debit Card which can be chosen at the checkout. We also accept PayPal Credit (Check it out on the PayPal website).
Our preferred method of payment is via the web shop or alternatively we can send a payment request via email. Only in extreme circumstances will be take card payment due to Security Risks.
We are pleased to offer a 30 days’ refund policy from the receipt of all Tuning products such as TMC Tuning Boxes, TMC Autoflash, Powerpedals & Personal Remapping Tools. Only if the products are complete and are in an unused and undamaged condition. The returned goods must be in a resalable state and any goods or accessories that accompany the returned product must also come back to us. The goods should also be returned with their original box, packing and accessories. To return an item please email email@example.com with the order details.
Orders from TMC are shipped daily on working days Monday through to Friday. As most items are delivered by DHL, UK items are usually delivered within 1-2 working days and International deliveries within 7 days (this can sometimes take up to 14 days though). Refer to question “How long does delivery take?” for more information above.
Please check the item listing for shipping charges. All shipping prices include packaging too.
As stated in an earlier question, we ship worldwide. If your unsure if we deliver to your country. Please contact us via our contact methods.
Some items are specially ordered or made to order. If not stated in the product description, you will be contacted upon purchase to confirm your happy with this. Special order items unfortunately cannot be returned.
There are two main methods of tuning modern diesel and gasoline engines , one is by chip tuning or re-mapping , this involves using a special interface to read out the program from the cars computer or ECU and then writing in a new program to increase performance. The second method is to use an external plug in Tuning Box or as some people refer to them 'Piggyback ECU' , these units connect into the existing wiring of the vehicle generally using original manufacturers connectors , a control unit (Tuning Box) is then attached which can over-ride the signals coming from the engines sensors to the cars ECU and alter them to allow the injectors or common rail to inject more fuel at certain times and increase turbo pressure to keep the air/fuel ratio correct.
Quite simply the analogue unit has no electronics inside and no microprocessor, its generally made of resistors inside a plastic box with a screw to increase or decrease fuelling , these are very cheap to make and are usually found on well-known auction sites, the risk with these units is that they have no set program to deliver the increased fuel or turbo pressure at specific points , instead they just increase fuelling or turbo pressure continuously even at idle which can cause the engine to run erratically and over time will likely cause damage and usually create a lot of smoke from the exhaust and possibly damage the turbo. This is a real danger on the newest vehicles fitted with Diesel Particulate Filters on the exhaust because if the filter becomes blocked and cannot be regenerated you will have to replace it at great cost . The analogue units generally will not work on a large number of modern cars due to the latest intelligent computers running the engine which can detect them and will cause the engine warning lamp to come on and the engine to go into safe mode (greatly reduced power and limited revs). A digital tuning unit has a microprocessor controlled computer board inside which is programmed with specific parameters for each individual vehicle to obtain the maximum performance without reaching the safety cut off limits set by the manufacturer, each unit is set up on a dynamometer so the results can be accurately measured , the digital unit will also not function until the accelerator pedal is pressed beyond a certain point at which you are demanding extra power , this means that no extra fuel is being added at idle and the extra fuel being injected is reduced again when the engine approaches maximum revs to avoid damage , put simply the digital unit is carefully designed using the latest technology to achieve the maximum performance safely from each individual make and model of vehicle, also the parameters in the digital tuning kit are hard programmed into the control chip so they can never alter over time or temperature. Multi-Channel Technology is used on almost all of our tuning kits, the advantages to this technology are huge, we have the ability to control not just the amount of fuel being injected into the engine but simultaneously the turbo pressure can also be altered to make the air fuel mixture correct. We can also use input signals from the engines camshaft sensor to read the engine RPM and make Live Tuning as you drive instead of a fixed map which can have too much increase at low revs and can put additional strain on the engine and gearbox. Our units also have the ability to read engine temperature so the tuning can be delayed until the engine reaches a safe running temperature before power is increased. This technology is much more complex than single channel tuning kits made by most other companies and costs significantly more to produce but the benefits both in quality and performance make the extra cost worthwhile. We also use 32-Bit and 64-Bit microprocessors for the fastest processing speeds.
All of the units supplied by TMC Motorsport will give up to 40% increase in B.H.P and up to 40% increase in torque depending on the vehicle, the vehicle will be noticeably stronger pulling away and over-taking , these units are superb for those having to tow a large trailer or caravan . All performance figures quoted on this website are given as an approximate guideline and will vary from car to car, figures can also be influenced by outside factors such as temperature, air quality, quality of fuel and accuracy of the dyno the vehicle is being tested on as well as maintenance of the vehicle. On fuelling : the units are sold mainly for their performance increase however almost all customers who have fitted one have noticed that if driving sensibly M.P.G will increase by up to 20% , this is not due directly to the tuning unit but more to how the vehicle drives after the tuning unit is fitted , its really down to common sense , if the vehicle pulls away easier in lower revs you don’t need to keep changing gears as often which reduces the amount of fuel used . This also means that you are not having to rev the engine hard to get performance which reduces stress on the engine and again reduces fuel consumption.
There are many good tuning kits available from various companies, but also many very bad ones which may cause serious damage to your engine leaving you out of pocket for hundreds or even thousands of pounds! The biggest difference between our tuning kits compared to most others on the market is that we use Multi-Channel Technology, the advantage of this is most noticeable on newer cars from 2007 onwards especially diesels fitted with Diesel Particulate Filters, a DPF is basically a collector of carbon/soot and is designed to capture most of the polluting carbon coming from your engine whilst you drive on short town journeys then when you use the motorway/highway at a maintained speed the vehicles ECU (computer) puts the DPF in to regenerate mode and uses extra fuel to superheat and dispose of the carbon away from the populated areas. Where problems arise is if you tune these engines just by increasing fuelling as you would have on older diesels, this creates more carbon/soot and the DPF can become blocked and if the dealer cannot manually re-generate it you may need to replace it and these are very expensive (in excess of £1000). With our multi-channel kits we also increase turbo pressure adding more air with the additional fuel, this will stop the DPF from becoming blocked and the car will also have more power than one tuned simply by adding fuel. TMC Motorsport can guarantee that our Digital Tuning Modules are of the highest standards available , most units carry the highly regarded German T.U.V certification/approval and are rigorously tested and guaranteed for 2 years. Some of our units can also be adjusted to nine different power settings by the customer depending on the level of power required. Our units are also safe to run on all vehicles fitted with diesel particulate filters. We offer excellent customer service and offer installation at our approved workshops or help for anyone wishing to self-fit . We offer these units for almost all of the modern range of diesels and also for most modern turbo charged petrol/gasoline cars as well as diesel vans and 4x4’s.
Our units are specifically designed to run within the manufacturer’s safety limits and tolerances, the extra performance runs within the tolerance of the engine and gearbox. The service intervals of the vehicle will not change however it is important that they be done on time and using original manufacturers parts , it is also very important to regularly check the engine oil level and top up if necessary with the correct oil as most modern diesel engines are designed to use some oil to increase the lifespan of the engine. It is also important to remove the unit before visiting your dealer as many car manufacturers will have issue with any performance upgrades. We offer additional engine warranty for those who wish to have added cover for mechanical parts, this is purchased as an additional item.
Generally not , most can be fitted by one of our trained technicians in less than 20 minutes , however some require items like intercooler to be lifted off the top of the engine to get the connectors on to the injectors underneath , this is not a job we would recommend to someone with no mechanical experience , most kits though are very simple to fit , we can give you advice depending on your particular car. The important thing is to make sure the unit is not fitted close to any high sources of heat and that all cables are safely tied to avoid getting caught in moving engine parts.
There are no laws against increasing your cars performance, your insurance company however require that you inform them of any modifications you make to your vehicle including changing wheels or fitting sports exhausts, it is your own choice if you wish to do this however many of our customers who have informed their insurance companies of their performance upgrade did not incur any additional loading on their policy or at worst had to pay a small sum for the increased cover , this is a small amount to know that if you are unfortunate enough to be involved in a collision that you will be fully covered.
No increase in emissions is negligible, some kits even reduce emissions!
It’s a personal choice really, both should give similar results at the Stage 1 level. For some people a Tuning Box is preferable if their car is under warranty as the unit can just be removed for servicing and re-fitted afterwards. ECU Tuning also gives excellent results and means that the method of tuning is invisible to the eye, one downside is that if the vehicle dealer has to install updated software from the vehicle manufacturer the chip tuning will be erased and will have to be re-done meaning you will pay again.
Don’t worry this is normal. We only show one image on the website as it would be confusing to show more than image. We have several different designs & colours of casings, these are used to accommodate the different sizes of circuit boards we use as different technologies are used for different makes and models of car.
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How quickly you receive our email confirmation can depend on your email provider and whether the email has been incorrectly marked as junk. Please add firstname.lastname@example.org to your safe senders list to ensure safe receipt. If you still cannot find it, please contact us via our contact methods.
If you have placed an order but then wish to change or cancel it, please contact our Customer Service department as soon as you can on either 03333355119 or email@example.com. We will try our best to make any changes, but we will be unable to do so if the order is already being processed in the warehouse and/or dispatched. Unfortunately, goods that have already been dispatched cannot be amended or redirected to an alternative delivery address.
Braintree our payment provider (Owned by PayPal) do not cover us or the customer for fraud unless the items sold are sent to the cardholder’s address. If you require the items to be sent to a different address you must first add your wanted delivery address to your PayPal account, then choose it as the checkout.
To see your local currency. If you use the PayPal option at checkout before completing the order & pressing the pay now button, at the top you can click to see the value of your Local Currency to £ (Sterling Pounds).
We only sell in £ Sterling Pounds however our payment provider accepts transactions in all currencies, to see the value of your local currency read the previous question.
If your delivery address is outside of the UK or EEC, you may have to pay import duties and taxes, which are levied once the shipment reaches your country. All international shipments may be subject to cross-border inspections by customs authorities while customs policies vary widely from country to country. You must meet any additional charges for customs clearance, and we recommend that you contact your local customs office for further information.
Please return any items in the original packaging (unless faulty) with a note inside stating your Name, Order ID & Any Other Relevant Information you feel necessary included to the following address: TMC Motorsport, Unit 8, 766 Upper Newtownards Road, BT16 1TQ, Northern Ireland, UK.
Once we have processed the refund it will usually take 3-5 working days for the funds to show in your account. This may vary depending on your bank.
We don’t personally offer Finance however we do accept PayPal Credit. Please visit their website for more details on this.