Ultimate Synchro Build Service – DSM Includes:

  • Large Double Synchro 1st – 4th Gears
  • 1-2 Shift Fork
  • 1-2 Hub & Slider
  • 1-2 Synchro Springs x4
  • 1-2 Synchro Shoes / Keys
  • 1-2 Hub & Slider
  • Center Diff Spider Gear Shims
  • Center Diff Torrington Bearing Upgrade
  • Drain / Fill Plug Crush Washers
  • Double Synchro 2nd Gear
  • 3-4 Shift Fork
  • 3-4 Hub & Slider
  • 3-4 Synchro Springs x2
  • 3-4 Synchro Shoes / Keys
  • Input / Output / CV Axle Oil Seals
  • Intermediate Shaft End Bearings
  • Shaft End Nuts
  • Shift Fork Roll Pins
  • Neodymium Trash Magnet
  • Transmission Filter Modification
  • Available Welded or 4-Spider Center Diff Upgrade

If you want the best shifting trans on the market with large double synchros from 1st-4th gears, this is it! This transmission build is designed for superior shifting, not high power. If you plan on making more than 350hp to the wheels, please consider the Dog Box Drag Transmission Build Service as it uses the strongest gear set possible!

This transmission has an incredible shift feel and quality unmatched by any other trans! You can race at the track and drive it to work the next day. This transmission is assembled with the highest quality materials and workmanship possible to assure a unit which works as intended and will live. It will shift beautifully, and operate quietly.


Jacks Transmissions has grown into a company which now services exotic and terribly complex DCT (dual clutch transmissions) used in the GTR, SST, Porsche, Audi, VW, and many more high end vehicles. Due to this exciting change, we have spent a lot of money for the state-of-the-art equipment needed to service these high dollar and expensive units. We have also designed and built many of our own parts for these vehicles.

All machine work, cleaning, and detail work is performed in-house by very talented technicians and engineers. The quality you get from Jacks Transmissions is an unbelievable bargain. We do not know of anyone else who cleans the transmission via a 110gal Ultrasonic and Pulse-Jet unit, or who employs such talented people.

Exceptionally clean units are one of the many reasons why our Transmissions and Transfer Case assemblies are of the highest quality in the business! We have state-of-the-art cleaning equipment which other transmission builders and service shops could only dream of.

With the best cleaning equipment, we also have a very clean facility. All units are built in a spotless environment using tools, and benches, which are clean and only used for assembly purposes. In other words, the same tools used to pull your dirty old transmission out of your car are NOT the same tools used to rebuild your pristine unit afterward. Take a look at the typical shop and check their tools. It is shocking how dirty things are in most shops and that dirt will end up in your unit. That does not happen here.

The quality and experience you get from Jacks Transmissions shows with the overwhelming number of high-end vehicles we service in our shop. Be a part of the rare opportunity to have one of the cleanest and most experienced specialty shops in the World service your transmission!

Our pricing structure was created to assure only the highest quality materials and workmanship. Anyone which beats our price is taking short-cuts which you will pay for in the end. Look into the details of our build services and you will see the additional attention we provide which is unique and cannot be duplicated.

We love the Mitsubishi transmission and have not forgotten that it is these units which got us to where we are today. We will continue to service them as we want to continue to support the community. This is a great opportunity for the Mitsubishi enthusiast to have a build using the same high-end equipment to service the Mitsubishi transmission as we use for the expensive exotic units. This means that the cleanliness and attention to detail is unmatched!

4-Spider Option Includes:

Center Diff Upper Torrington bearing

Center Diff Side Shims

New Spider Gear Kit with Pinion Gears

Machined Cross Shaft
Machined Lower Housing

We will also weld scoops to each side of the center diff housing to help with lubrication.

Bearing preloads are reset to our specs for maximum bearing and gear life.

Additional Information

1-2 Shift Fork combined with our efficient double synchro makes for a very strong and reliable assembly. You will never have to worry about a broken 1-2 fork again.

3-4 Shift Fork

Jacks Trans machined double synchro 1st gear upgrade, with removed lip, to allow for longer synchro life.

Jacks Trans machined double synchro 2nd gear upgrade, with removed lip, to allow for longer synchro life. Please note that this gear is NOT the same as the double synchro 2nd found in the 2G. Our gear is designed with more room for synchro wear and a more precise fit.

Jacks Trans machined Double Synchro 3rd and 4th gear upgrades,with removed lip, to allow for longer synchro life and superior shifting performance. More info HERE

All Bronze 5th Gear Synchronizer Blocker Ring (Excludes early 90 style 5th)

1-2 Synchronizer Hub
1-2 Synchronizer Slider

3-4 Synchronizer Hub
3-4 Synchronizer Slider

1-2 Synchronizer Springs (x4)
3-4 Synchronizer Springs (x2)

1-2 Synchronizer Shoes
3-4 Synchronizer Shoes

Input, Output, and Axle Seals

Tapered Bearings – Intermediate Shaft.

1-2, 3-4, and 5-R Roll Pins

Drain Plug / Fill Plug / Reverse Idler / 5-R Rail Detent Washers

Neodymium Trash Magnet

No Additional Cost: 2-Spider Diff with Torrington Bearing Upgrade or Welded Center Diff. The 2-spider center diff is weaker than the welded diff, but is easier to drive on. Welding the center diff makes it the strongest part in the transmission and raises the HP capability.


Any additional parts needed which are not listed or not part of this build will cost extra to replace. We will email pictures and detailed information if this is the case. We know you do not like surprises, so we try to make this process as painless as possible. If this turns out to be the case, though, please keep in mind that we just want you to have a high quality built assembly. Having your vehicle down is bad enough, so why cut corners and risk it again? Quality is the key here and sometimes it costs more to do this on a specialty or aging platform. Simply put, it is not worth the risk of using a sub-par component if an inspection reveals it is a weak link.


All machine work and cleaning is performed in-house. We also spend a lot of time on synchro timing, alignment and operation to give you the best shift possible. Click -> Synchro Blueprinting


Shipping your Transmission (or complete car) to us is simple! Most assemblies are shipped in a double walled custom made box. Your assembly will be sitting snugly, and safely, in preformed foam pads to assure safe delivery.

In certain situations, though, we may need ship via a freight pallet. Please email or call us if you have shipping questions or for a quote.

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Ultimate Synchro Build Service - DSM

  • $2,449.00

Available Options

Tags: DSM Rebuild, dsm trans rebuild, rebuilt service, ultimate double synchro, ultimate dsm, ultimate synchro

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Whether you need a part to complete your build or want us to do it from the ground up, we've got you covered.
Let us take your project 'from Start to FINISH!'

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3920 North Weber Street Colorado Springs, CO, 80907

Hours: Mon-Fri 8:30AM-7PM MT





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