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Ford MMT6 Gearbox Transmission Service and upgrade

Ford MMT6 Gearbox Service & Upgrade Ford (6000-GL-AA) | Mountune

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Availability: Turnaround time is usually 7-10 days, Contact us form more information
Product Code: 6000-GL-AA

Vehicle Model*:
Focus RS [Add $165.00]
Focus ST

Gearbox Service Upgrades*:
Add Focus RS Quaife ATB Differential to service [Add $949.00]
Add Focus ST Quaife ATB Differential to service [Add $899.00]
Do Not add Quaife ATB

Surface Treatment Options*:
Add WPC Surface Treatment [Add $650.00]
Do not Add WPC Surface Treatment

Shipping Option*:
Add Shipping Option [Add $199.00]
No Shipping required, I will deliver.

Description FAQs
Ford MMT6 Gearbox Service


Ford Focus ST 2013-2018
Ford Focus RS 2016-2018

Having issues shifting smoothly through the gears? Our Ford MMT6 Gearbox service and upgrade replaces all the fragile standard synchros with our carbon lined heavy duty components along with all new upgraded bearings. This ensures accurate selection when going through the gears, even under hard acceleration. A full teardown, motorsport grade cleaning and inspection are performed before re-assembly making sure your gearbox is more reliable and performs better than new. Please read our FAQ page located at the tab above.

Shipping your gearbox to us is easy. We send you a heavy duty shipping container with return label. Simply place your gearbox in the container and send it back to us for upgrading. Select this option when checking out. This option applies to the lower 48 United States only.

Add an optional Quaife ATB Differential or WPC Gear and Shaft treatment for maximum performance.

  • Faster, more accurate shifting
  • Upgraded components and bearings
  • Optional Quaife ATB
  • Optional WPC Treatment for all Gears and Shafts

We use and recommend MOTUL MULTI DCTF Transmission fluid for superior lubrication and performance.

About WPC
he WPC process is unrivaled in treating engine parts and other surfaces that have contact points of friction. WPC is superior because it is not a coating; it is a permanent surface treatment that reduces friction. It's unique micro-dimple formation pattern greatly reduces friction and is unmatched by conventional methods of surface treatment.

* Note - Prices quoted include parts and labor for gearbox only and does not include removal or installation of gearbox in car or shipping of gearbox to and from Mountune.

Recommended product
MOTUL MULTI DCTF - Dual Clutch Transmission Fluid (1L)
Sale price:$18.10


Average Rating: Average Rating: 5 of 5 5 of 5 Total Reviews: 4 Write a review »

  1 of 1 people found the following review helpful:
5 of 5 Excellent Upgrade! June 18, 2021
Reviewer: Michael Kulp from College Point, NY United States  
So.. After installing Mountune's long block with Darton sleeves, lightweight steel crank/flywheel and head with v3 cams, my 3rd and 4th gear synchros said no. Mountune sends a crate for my tranny and I have them do their upgrade with WPC treatment and Quaife differential.

One word: Transformational.

The tranny shifts perfect and with the Quaife upgrade, it is now a noticeably more controllable serious performance car. In my opinion, you get what you pay for with Mountune, every part I've ordered from them has been exceptional in quality. If you're looking for a top notch installer in the NY Metro area, look up Precision Auto Works in Long Island City. The owner, Mike did all of my work and I couldn't be happier - he's a seriously talented technician. I'm 60, this car makes me laugh like I'm 18...

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  1 of 1 people found the following review helpful:
5 of 5 Super smooth and quick shifting October 23, 2020
Reviewer: David Davis from Spring Valley, CA United States  

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  1 of 1 people found the following review helpful:
5 of 5 Grips and Shifts August 10, 2020
Reviewer: Jason Offord from Fairport, NY United States  
The process for shipping and returning the transmission is well thought out and pretty easy, other than lugging 130lb to FedEx.  The new diff definitely grips hard and pulls through the corners.  Straightline stability has improved.  The only thing I would have appreciated was more feedback from Mountune about the progress of the work being done.  What step are you on?  What was the condition of the trans when it was disassembled?  Other than that I'm very pleased with my purchase and the quality of the work done.

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  1 of 1 people found the following review helpful:
5 of 5 perfect fit stopped problem May 31, 2019
Reviewer: Charles Anson from Bradenton, FL United States  
Let's say 4.5 stars, Mountune shipping option on this takes 10 days each way, not the 4 or 5 they try to sell you.  That being said, I just put the first 300 miles on it today, it feels awesome.  I've got all the bolt-ons, ford performance tune, stock turbo, south bend stage 4 clutch, short throw and short shifter arm.  I've puked 3 sets of synchros in the last year.  Albeit it was 30,000 miles in that year.  Ford did their part, they could only replace the transmission, they warrantied it 2 times.  The last time lasted 2 weeks with me going easy on it.  I couldn't believe it.  Mountune thinks it looked more like a refurbished tranny.  They found one bearing .012 too tight!  Anyway, I got the whole treatment, WPC, new synchros, they cleaned the thing completely out, including the LSD I already had.  I'll report back every 6 months or so.  I'm praying this works, but so far so good I would say.  The shipping was the only slow part, the work did not take long.

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