FAQ

  1. What fluid should I use and how much?
  2. What are the components of a TKO 5 speed?
  3. What are the components of a Magnum 6 speed?
  4. How long is the break-in period?
  5. How do I measure for my custom driveshaft and when can I expect to receive it?
  6. How do I calculate the driveline angle?
  7. What is the difference between internally and externally balanced engines?
  8. How often should I change my fluid?
  9. What is the best way to shift quickly/smoothly into 3rd gear with a White Lightning Shifter?
  10. Can I use mechanical linkage with my new Tremec Transmission?
  11. How do I set up my Hydramax to get smooth, light pedal effort?
  12. What would cause my clutch to have a short engagement/disengagement?
  13. What fluid should I use in the master cylinder with my Hydramax system?
  14. How do I dial indicate my Bellhousing?

Q: What fluid should I use and how much?

Transmission fluid is the life blood of your transmission. Proper wear and synchronization depends on using correct fluid. DO NOT USE aftermarket fluid in this transmission. Use only GM Synchromesh (part# 12345349), Pennzoil Synchromesh or Mobil1 ATF. Any other fluid used may cause premature wear and grinding synchronizers and will VOID YOUR WARRANTY.

NOTE: You can use standard Dexron III ATF for break-in, but it must be drained after the break-in period and replaced with Synchromesh or Mobil1 ATF as your permanent fluid.
Filling Transmission Case:
  1. If you removed the rubber bung from the tailhousing during test fitting, replace before filling transmission or, if available, install your driveshaft.
  2. Remove the square headed filler bolt located on the side of the main case about half-way up. (lower hole is the drain plug)
  3. Using a hand operated fluid pump, install 2 quarts of GM Synchromesh (part# 12345349) found at any GM dealership or Pennzoil Synchromesh (same stuff but cheaper) found at big box retailers like AutoZone. After 2 quarts, slowly add fluid until it reaches 1/8” from the bottom of the fill hole when transmission is level. You can easily test this by placing your small finger in the hole to the first knuckle. You should be able to feel the fluid by bending your finger.
  4. The TKO 500 & 600 Tremec transmissions require approximately 2.42 quarts. The 6 Speed Tremec Magnum transmissions require approximately 3.45 quarts.

  5. Replace the filler bolt.
  6. Store extra Synchromesh in an airtight container in a dry environment to prevent water absorption. Improperly stored fluid should be discarded.

Q: What are the components of a TKO 5 speed?

TKO 500 & 600
TKO 5 Speed
Components
  • Vent Tube
  • Spring Retention Bolt (Do Not Remove)
  • Mechanical Speedometer Port
  • Neutral Safety Switch
  • Electronic Speedometer Port
  • Fill Plug
  • Drain Plug

Q: What are the components of a Magnum 6 speed?

Magnum 6 Speed
Components
  • Reverse Lockout
  • Fill Plug
  • Drain Plug
  • Mechanical Speedometer
  • Vent Tube
  • Electronic Speedometer Port
  • Reverse Light

Q: How long is the break-in period?

Your new transmission has a 500 mile break-in period, during which the transmission should be operated rather gently to allow the synchronized gears to self-tolerate. After this break-in period, drain your transmission into a clean pan, check for abnormal particulate in the fluid, and refill using GM Synchromesh, Pennzoil Synchromesh, or Mobil 1 ATF.

NOTE: Some sloughing off of material is expected when performing the break-in fluid change. A magnet in the bottom of the transmission will trap ferrous particles, but it is normal for some aluminum and brass to be suspended in the fluid.

Q: How do I measure for my custom driveshaft and when can I expect to receive it?

The measurement is known as "seal to center" and is the distance between the case of the transmission next to the rear seal and the centerline of the pinion yoke. When ordering a driveshaft you must complete the following form. Email this completed form to support@americanpowertrain.com, or fax the form, front and back, to 480.393.4180. How to measure the driveshaft and determine your rear universal joint size is demonstrated on the form. For late model Mustangs, a second page is provided to determine your rear flange size. Turnaround time, once your form is submitted, is 24 to 48 hours to build along with the amount of time require to reach your location via FedEx Ground (1 to 5 days).

American Powertrain Driveshaft Order Form

Q: How do I calculate the driveline angle?

Finding your driveline angle is the easy part; deciding what angles work best for you, however, can be a challenge. Please review the following video for a demonstration of driveline angle affect. Driveline Angle Affect.

Simply put, an incorrect driveline angle can create vibration, cause premature universal joint failure, and reduces power to the rear wheels. Consider the following article from hotrod.com. How To Set Pinion Angle.

Tremec has created a free app for smart phones that measures the driveline angles and displays whether they are within specification. Below is a link to a PDF of the app's instructions as well as a link where the app can downloaded.

TREMEC Driveline Angle Finder App Instructions
Get The Tremec Driveline Angle Finder App

Q: What is the difference between internally and externally balanced engines?

Internally balance engines have weights added to the crankshaft counterweights to achieve proper balance in the rotating assembly. The rotating assembly consists of the crankshaft, connecting rods, pistons, and wrist pins. To achieve proper balance in the rotating assembly, externally balanced engines require the use of added weight to the flywheel/flexplate, or weight removed from one side of the flywheel. Below is an excellent article from hotrod.com to further explain internal and external balancing and why it is important to select the correct flywheel/flexplate for your engine.

How to Balance An Engine - Engine-Balancing Basics

Q: How often should I change my fluid?

According to Tremec:
"Maintenance Recommended oil change intervals should be based on specific usage. In most cases a “fill for life” is adequate, while in severe applications such as drag racing, or road racing a more frequent fluid change should be prescribed. Excessive heat will cause most fluids to breakdown and ultimately cause damage to the transmission."

Q: What is the best way to shift quickly/smoothly into 3rd gear with a White Lightning Shifter?

The White Lightning Shifter is a superior shifter in many ways. Occasionally, however, performance drivers struggle with the 2nd to 3rd gear up-shift. The issue arises when the "H" pattern, we all grew up with, is performed and 3rd gear is missed or feels "notchy". This can be especially prevalent when shifting quickly. Take a look at the following video and try performing the up-shift with an open palm. The White Lightning will move to a perfect 3rd gear alignment on its own.

Q: Can I use mechanical linkage with my new Tremec Transmission?

Yes! Consider, however, that you are installing a modern performance transmission and then attempting to actuate it with a combination of parts designed over 50 years ago. American Powertrain’s patented HYDRAMAX hydraulic systems and components are the most advanced systems on the market today. For more on the Hydramax system, please review the following video.

Q: How do I set up my Hydramax to get smooth, light pedal effort?

If your clutch pedal is hard to push, the first thing to check is for any binding in the linkage between your clutch pedal and the master cylinder. Secondly, check to make sure you have not created too steep of an angle in the actuation of the rod moving in and out of the master cylinder.

Next, verify your pedal ratio is within specification. The pedal ratio is the distance that your foot moves versus the distance the rod going in and out of the master cylinder moves. Pedal ratio is an important component in creating a smooth pedal feel with excellent clutch modulation. One of the biggest mistakes made in hydraulic conversions is creating a low pedal ratio.

Ideally, you want between 5:1 and to 6:1 ratio. This means essentially that if your master cylinder rod moves 1”, your foot needs to moves 5-6”. The Wilwood master cylinder supplied with our Hydramax kits require 1.12" of travel; this means that your pedal needs to move 6" to achieve a 5:1 ratio. Most stock pedal pivot points give an excellent pedal ratio, however if you move the rod lower on the pedal, or you are building a custom car and you have a ratio lower than 4:1, you may consider artificially raising the point at which the pedal rod hits the pedal arm to increase this ratio. If this is not possible, you can also consider moving the master cylinder bracket assembly lower on the firewall to increase the rod angle and therefore the pedal ratio.

Hydramax kits

Q: What would cause my clutch to have a short engagement/disengagement?

If your clutch engages or disengages too quickly, you may have an incorrect pedal ratio. The pedal ratio is the distance that your foot moves versus the distance the rod going in and out of the master cylinder moves. Pedal ratio is an important component in creating a smooth pedal feel with excellent clutch modulation. One of the biggest mistakes made in hydraulic conversions is creating a low pedal ratio.

Ideally, you want between 5:1 and to 6:1 ratio. This means essentially that if your master cylinder rod moves 1”, your foot needs to moves 5-6”. The Wilwood master cylinder supplied with our Hydramax kits require 1.12" of travel; this means that your pedal needs to move 6" to achieve a 5:1 ratio. Most stock pedal pivot points give an excellent pedal ratio, however if you move the rod lower on the pedal, or you are building a custom car and you have a ratio lower than 4:1, you may consider artificially raising the point at which the pedal rod hits the pedal arm to increase this ratio. If this is not possible, you can also consider moving the master cylinder bracket assembly lower on the firewall to increase the rod angle and therefore the pedal ratio.

Hydramax kits

Q: What fluid should I use in the master cylinder with my Hydramax system?

Use only DOT3 or DOT4 high temperature non-silicone brake fluid. Use of other petroleum based fluids will result in O-ring seal failure. A high temp race grade DOT4 fluid is recommended to reduce heat absorption. We recommend EBC, Wilwood, or Pentosin brands of high temp fluid for their high boiling point and excellent stability.

Q: How do I dial indicate my Bellhousing?

The Driven Man/American Powertrain Bellhousing Alignment Measurement and Correction

Background: Modern transmissions use tightly tolerated taper roller bearings to support the input shaft. These bearings are far superior to the ball bearing assemblies of older transmissions; however their exacting specifications require that the input shaft has almost perfect linear engagement to the pilot bearing in the crank shaft. Improper centering of the transmission to the crank can cause premature wear on the input shaft bearings, creating noise, vibration and the eventual failure of internal parts of the transmission.

Due to manufacturing abnormalities in traditional and modern bell housings and scatter-shields it is necessary to measure the accuracy of your bell housing as it relates to the crank shaft. This will insure that the input shaft, located by the bore hole in the back of the bell, lines up directly with the crank.

NOTE: IT IS IMPERITIVE THAT YOU MAKE THIS MEASUREMENT. FAILURE TO CORRECT A MISALIGNED BELL HOUSING WILL VOID YOUR TRANSMISSION WARRANTY.

A video of this procedure can be viewed here:

You will need:
  • A magnetic base dial indicator with a .001” resolution (.0005” preferred)
  • Large ratchet handle, breaker bar or flywheel tool to turn crank
  • Appropriate tools for tightening bell housing bolts
  • Permanent black marker (Sharpie)
You may need:
  • Appropriate tools for removing dowel pins
  • Offset dowel pins to correct out of spec condition
Proceedure:
  1. With the flywheel installed if possible, place the bell housing on the back of the engine and fasten with at least four bolts, insuring that the bell is seated against the block.
  2. Place magnetic indicator on the flywheel (or crank hub if flywheel is not installed). IT DOES NOT NEED TO BE CENTERED IN THE CRANK. Set the measuring finger on the inside of the bore of the bell housing (see photo) at the 12-o’clock position.
  3. Zero the indicator dial at 12 o’clock. With a permanent black marker, mark a zero on the back of the bell at 12 o’clock.
  4. Turn the crank until the measuring finger is at the 3 o’clock position. Record the measurement with the marker. Make sure you record if the result is positive (to the right of zero) or negative (to the left of zero).
  5. Repeat step four at the 6 o’clock and 9 o’clock positions, recording your results. Then return the indicator to 12 o’clock and make sure it measure zero. If the indicator does not measure zero at 12 o’clock then the base has moved during the procedure and you will have to repeat steps 3 through 5.
How to interpret the numbers:

The acceptable tolerances for Tremec transmissions is .005” of total runout. The following formula will tell you how much runout you have.

Reading at 12 o’clock – Reading at 6 o’clock = Vertical Axis Run Out

Reading at 3 o’clock – Reading at 9 o’clock = Horizontal Axis Run Out

Examples:
  1. 12 o’clock = 0
    And
    6 o’clock = -.004
    Then your Vertical Runout is 0 - -.004 = .004” (within tolerance)
  2. 3 o’clock = .009”
    And
    9 o’clock = .006”
    Then your Horizontal Runout is .009 - .006 = .003” (within tolerance)
  3. 3 o’clock = -.008
    And
    9 o’clock = .013
    Then your Horizontal Runout is -.008 - .013 = .021” (.016” out of tolerance)
Interpreting The Numbers:
  • If you are out of tolerance (> .005” +/-) on only one axis, then you will correct directly along that axis. The vertical axis will be corrected by a direct north or south movement of the bell housing, the horizontal by a direct east or west movement.
  • If you are out of tolerance on both axes, then you will be correcting along a diagonal. For example, if you’re bell housing is sitting .008” to the south (down) and .009” to the east (right) of center then you will correct toward the northwest to move the bellhousing up and to the left.

If your two axis measurements are less than .005”, as shown in example one and two, then your bell housing is within tolerance and you can proceed to install your transmission.

If the number is greater than .005” (+/-) then you must use the following procedure to correct the runout.

  1. Remove indicator and bell housing and set aside for later use.
  2. Remove dowel pins using one of the following methods:
    • Some engines have punch holes behind the pins. If you have this style of engine you can simply use a pin punch and a hammer to remove the old pins.
    • Grasp with vise style pliers and slowly turn pin while pulling away from the block.
    • Weld a steel nut to the end of the pin and twist assembly out with a wrench or vise style pliers.
    • Our favorite method for removing ornery pins involves the use of an aerosol spray freezing agent available at most parts stores. Simply place vice style pliers on the pin, heat the block around the pin area, spray the pin with the freezing agent and pull. The pin will shrink away from the heated block and usually come away very easily.
  3. Once the dowel pins are removed you will need to install “offset” dowel pins in the block. Offset dowel pins come in .007”, .014” and .021” sizes and correct for twice their value. Therefore, a .007” dowel pin will correct for as much as .014” of total runout. These pins are available from us, or from your local speed shop or racing supply retailer.
  4. Remove the dowel pins from their package and using the permanent marker or bright nail polish, mark the high side of each pin. This will help you align the pins when you press them into the block.
    NOTE: THE MOST ACCURATE WAY TO FIND THE CORRECT POSITION FOR THE DOWEL PINS IS TO DETERMINE THE POSITION WHERE THE BELL HOUSING BORE IS CLOSEST TO THE CENTER OF THE CRANK AND POINT THE HIGH SIDE OF THE OFFSET PINS AT THAT POSITION. YOU CAN FIND THIS POSITION WITH THE DIAL INDICATOR. SEE ILLUSTRATION:
    !!ALWAYS POINT HIGHPOINT ON PINS IN THE SAME DIRECTION!!
    DIAL INDICATOR ILLUSTRATION
  5. Once you have marked the high side, tap the pins into the block using a brass hammer, dredge or hardwood block to avoid mushrooming the pin. A light petroleum based lubricant should be used. Approximate the direction of correction as described above. In the example above we would put a .007” dowel pin in, with the high side pointing northwest.
  6. Once installed, place the bell housing back on the block and repeat the runout procedure. If you are still out of tolerance you can turn the new pins to fine tune their position. Most dowel pins have a slot or Allen head hole to make it easy to make fine adjustments after installation.
  7. Once you have reached a runout condition of less than .005” total runout, record your four measurements on this document and keep for warranty purposes.
Final Measurements:
12 o’clock ______________
3 o’clock_______________
6 o’clock_______________
9 o’clock_______________
Vertical Runout __________
Horizontal Runout ___________
Thank you for taking this important step in the installation process. If you have any questions or need help interpreting your results you can call us anytime at 931.646.4836.