Transmissions

Having problems keeping your GM TH-350 or TH-400 from living through the tough derbies?  Try one of our derby prepped transmissions with Low and Reverse gears only.  Neutral and Park are still functional, but second and third disappear.  This makes for a transmission that can handle much more abuse.   They will not shift out of low under full throttle conditions like many of the competition's rebuilt transmissions.   These units take a little more time to build, so to keep final cost down, only the important gaskets, seals, and clutches are replaced.  I personally have not ruined one of these transmissions, except for breaking cases, which were chassis design problems. All transmission require core exchange.

Derby TH-400   $400

Derby TH-350   $350

If you want the most durable Derby General Motors automatic transmissions, at an economical price, give us a call. 

Core prices - TH400 $100

                    TH350  $50

Transmission Coolers

We firmly believe in the benefits of a quality transmission fluid cooler.  We DO NOT recommend any cooler with push on ends, hose clamps, or similar attachment methods, and NEVER use fuel line for hose.  All coolers we sell use 3000 psi rated, internal steel wire braid hydraulic line and fittings.  Hot oil spraying on you during a derby will not only burn you if it directly contacts you, it can cause a severe car fire also.  We also DO NOT recommend using coils of copper tubing for a cooler.  The tubing has no internal or external heat transfer fins.  Below is a photo of a proper cooling tube.  This is a cut away of a high quality finned cooler, similar to the ones I use in my applications.

The only heat transfer occurs on the surface of the tubing on copper coils.  This means that the fluid in the center of the tubing does not cool.  I have checked the temperature of the cooler in a set up like this and have found the cooler water to be as little as 120 degrees when the transmission fluid itself is over 280.  On my coolers, the temperature of the water in the cooler tank is the same as the transmission fluid, showing proper heat transfer.  Just because you have a cooling setup doesn't mean it is truly cooling and saving your equipment.  Check out our selection of coolers, fans, water tanks, and other items below.  You can buy the individual parts or call for complete set ups.  Compare out cooler and fan prices with Summit or Jegs, and you'll find we are cheaper.  Click on photos for a larger image.

Here is the tranny cooler I use in all my cars except the heavy 64-66 Imperials.  It flows 6 gpm, has 300 psi burst rate, 1/2 npt fittings, and weighs 7 pounds.  Cooling fin area is 12x3x4, and overall size is 16x4x6.  Suited for water tank applications only.
TC-1 $89

We offer complete setups that are easy to bolt in.  The combo's include transmission fittings for GM applications, hydraulic line, cooler, and water container, or if using the air cooler and fan, the proper mounting brackets. 

NEW!  King Cool II.  This electric fan cooled transmission cooler is made of the finest parts.  A HUGE 12x23 aluminum finned cooler with tube heat transfer fins is mounted in a sturdy metal frame.  Plumbed with 3/8 hydraulic hose, transmission fittings, 12 volt 900 cfm fan, and an aluminum shroud makes this a cooler that will stand up to the most demanding derbies.  This cooler comes with or without legs.  All are shipped with no legs welded on for easier and cheaper shipping.  You can also mount this cooler with a couple of pieces of angle iron to your rear seat brace to keep if off the floor pan of the car.  Also available with an additional fan if desired.

Cooler with legs                                 $265

Cooler without legs                             $250

Optional front guard                            $25

Additional Fan                                    $50

Here is the most economical transmission cooler we sell.  Gasket sealed canister, TC-1 cooler inside, hydraulic hoses, transmission fittings.  Weld on your mounts or simply bolt in.  This cooler also will fit in the passenger side seat area of a GM sedan if you cut out the foam and springs.
ETC-3                                    $175

Our next cooler available comes housed in a sealed 20 gallon can.  This unit has front and rear 1 1/2" drain plugs, is constructed of 18 gauge steel, comes with filler hole, cap, angle iron mounts with holes.  When you fill this unit in the spring it is ready to go all year, if you wish to leave it full in one car.  Can be mounted many different ways.
20 Gallon cooler                           $265