1955-57 Bel Air Tri 5

Offers  five and six-speed conversions for
Small Block, Big Block builds, and even LS swaps

Our line of products offers simple ways to upgrade your 3 or 4-speed to a Tremec five-speed or a complete automatic to five or six-speed overdrive.
For the customer that wants more fun & drive-ability out of their Shoebox, we have you covered.

   Experience the MDL Difference

  • We extend the manufacturer’s warranty by an extra year… with a 1-year grace period.
  • We offer the best in the industry customer service.
  • When you purchase a complete MDL Conversion Package you get, lifetime technical support.


 VIDEO Cruising ina ’55  on the highway with a new TKX



Modern DriveLine
Has kits
for the customer that already has usable 3 or 4-speed ‘Muncie or Saginaw’ transmission components in their TRI-FIVE.

We have kits that allow you to use your existing 168-tooth capable bell-housing ( GM 621 or equivalent ), flywheel with 11″ clutch pattern, stock clutch pedal, and mechanical clutch release.  

Whether you are converting from Auto to Manual or just want an upgrade, we have a solution for you.
We can supply everything you need from the back of the block to the driveshaft.

You get all the parts you need and none you don’t.

  • All are backed by the industry’s best 2-year warranty from MDL ‘starting from the date of install.’
  • Lifetime Tech Support on all MDL
  • You will need to select a clutch matched for your horsepower & use.    Need Help… give us a call.
  • We will use any existing parts you have that we can… there’s no need to buy new if you don’t have to.


Click this link to read an Article about a TKO in a Shoebox

You will have to select a clutch matched to your horsepower & use it if you need help request a quote below.

Solutions are TAILORED to your needs
With many or all of the following:

TREMEC 5 or 6-Speed Transmission with Shifter



TKX Five Speed Single Overdrive Conversion up to 750hp.

Images above of a TKX and its clearance, A classic shift lever, and ball, and to make clutching lite and smooth a hydraulic system.


For higher torque applications or you’re a ‘spirited driver,’ the TKX series five-speed is the latest offering from Tremec
Check out these stats.

Rated for 600lb/ft of torque, will support shifting up to 8000rpm
Thanks to triple cone hybrid sintered synchronizers from the Tremec T56 Magnums have to make your driving experience the best.

The new end-loading design makes for a stronger case with a new sleeker profile, eliminating top covers, that would have restricted room in the tunnel.

Click here to read more about the TKX




The TKX offers a little more adjustment approx. 5/8″ at the tail shaft vertically for the driveline angle. Perfect for Pro-Streeters who love to tuck the rear suspension up into their ride.

The MDL conversion packages are as complete as possible.
You get ALL the components you need whereas competitors’ packages provide only the basics.
When comparing costs be sure you are comparing apples to apples on the contents, quality & after the order service.

MDL is a stocking distributor

A little Information on 1957 Chevy Factory Manual Transmissions


Click or call for a customized quote for your requirements.   208-453-9800

Install Photos