Product Support & FAQ



Q: What type of fluid does TREMEC recommended?

A: For all TKO 5-speed models, TREMEC recommends TREMEC HP-MTF, GM Synchromesh™ or Mobil 1 Synthetic ATF. For all other aftermarket models we recommend Dexron III ATF

Q: Why use automatic transmission fluid in a manual gearbox?

A:  Some TREMEC transmissions are designed specifically to use automatic transmission fluids (ATF) for good shift quality in cold conditions, compatibility with synchronizer friction materials, and minimized parasitic drag to maximize power to the wheels.

Q: Why not use hypoid gear oil?

A:  Hypoid gear oils are designed to withstand sliding actions at the meshing interface of bevel gears.  Some hypoid oils contain extreme pressure additives that are corrosive to certain non-ferrous metals that are used in transmission parts like bushings and synchronizer rings.  Also, the friction coefficient of some hypoid gear oils may be incompatible and can cause poor shifting.  Both of these conditions can result in premature or excessive wear and failure.

Q: How often should I change my manual transmission fluid?

A: Under normal driving conditions the fluid should never require changing.  For severe driving or racing, fluid changes should be made frequently, especially when operating temperatures of the transmission fluid exceed 250°F.

Power & Torque

Q: How much torque can each of your transmissions handle?

A: Transmission capacity is related to torque and vehicle weight, not horsepower. For complete transmission specifications, please click on the appropriate product link below.

Application Engine Torque Capacity RPM Rating
T-5 5-speed manual transmission
Ford SBF 300 lb.-ft. 6,700
TKO 5-speed manual transmission
GM Any 500 or 600 lb.-ft. 6,200
Ford Any 500 or 600 lb.-ft. 6,200
Magnum 6-speed manual transmission
GM LS 700 lb.-ft. 7,800
Ford Modular 700 lb.-ft. 7,800
Magnum XL 6-speed manual transmission
Ford Mustang Modular 700 lb.-ft. 7,800
GM LS 700 lb.-ft. 7,800

Note: Torque and RPM ratings may vary based on vehicle use, driveline configuration and quality of product installation.


Q: How does a manual transmission work?

A: The function of any transmission is to transfer power from the engine to the driveshaft and wheels. Gears inside the transmission change the vehicle’s drive-wheel speed and torque in relation to engine speed and torque. From the basic four-speed manual in a car from the ‘60s to the most high-tech seven-speed in a car of today, the principles of a manual gearbox are the same. The driver must shift from gear to gear, transferring power from the engine to the differential using a clutch and gears that are manually selected using a gear selector (“stick”). Clearly, a stick-shifting manual transmission is one of the main components in a fun-to-drive car. For a logical and simple explanation on how a manual transmission works, we recommend a short YouTube video from LearnEngineering.

Q: What is a clutch?

A: The clutch is used to couple the engine to the transmission so that power can be transferred. The clutch is also used to disconnect the engine from the transmission to interrupt power transfer during shifts or while the vehicle is at rest and idling with the transmission in gear. Learn more by viewing the Bringing Knowledge to the World YouTube video: “How a Clutch Works!”

Q: Which clutches are recommended for TREMEC transmissions?

A: TREMEC does not manufacturer, sell, or provide recommendations for clutch brands or models. This question best is handled by a reputable clutch manufacturer or authorized TREMEC Dealer/Reseller.

However, TREMEC users should be aware of the effects that an incorrect clutch can have on drivability and durability of the entire car, including engine, transmission, driveline, and chassis.

Q: Which TREMEC transmission will work best in my application?

A:  TREMEC offers a variety of high-performance ‘street-oriented’ products to serve general automotive enthusiasts and sportsman racers.  As a manufacturer we offer limited application and racing support, but we do have many dealers in place to address those needs.  For help finding the appropriate dealer, please use our Distributor Search function, or contact us using the “Contact Us” page.

Q: What parts/tools do I need to install one of your transmissions in my car?

A:  In most cases, installing a TREMEC to replace your factory transmission requires modification to your driveshaft, crossmember, and clutch/bellhousing arrangement amongst other things. However, in some cases the swap can be done with little-to-no specialized tools.

At a minimum, you’ll need the following:

  • Transmission jack
  • Flywheel wrench
  • Wrenches
  • Spline alignment tool
  • Socket set
Q: My transmission makes a loud whining sound in reverse. Is this normal?

A:  Yes.  Reverse gears in many manual transmissions are of the ‘spur’ type, or feature straight teeth.  By design they are noisier than the helical cut forward gears featured in a TREMEC.  Thus, the reason they are not used for forward speeds. Additionally, TREMEC does produce transmission models with fully synchronized, helical reverse gears.


Q: Which of your transmissions offers the best fuel economy?

A:  The purpose of transmission gearing is to allow the engine to operate in its best ranges of performance and economy at various vehicle speeds & loads. Magnum offers optional double overdrive ratios as deep as .50:1 for a 50-percent reduction in RPM in sixth gear and a .63:1 ratio.  Higher (numerical) final ratios are available on our TKO and T5 models.  Click here to see the TREMEC Performance Product Guide for more details.

Q: I'm not too worried about fuel economy, so why should I care about overdrive?

A:  The overdrive feature of a TREMEC transmission provides many benefits beyond fuel savings.  The significant drop in RPM during highway use will greatly extend engine and accessory life while improving drivability and performance with dramatic interior noise reduction.

Q: Which TREMEC transmission is best for drag racing?

A:  For low to moderate torque/horsepower engines, The TREMEC TKO 5-speed is often the preferred choice of hardcore sportsman drag racers and weekend warriors due to its high strength to weight ratio.  In the case of a weekend warrior, the TKO offers durability at the track while proving good drivability and fuel efficiency for on-highway use. For more ‘race-only’ applications, the TKO is also an ideal platform for race modifications, with a proven track record to support it.

For higher torque/horsepower street/strip combinations, the Magnum is the best choice due to its greater capacity to handle torque along with excellent high-RPM shift capability and double overdrive ratios.  Magnum transmissions can deliver exceptional drag strip performance with race-only modifications.  In either case you should be aware that modified/altered products are not covered under warranty.

Q: Which TREMEC transmission is best for road racing?

A:  Again, the TREMEC TKO 5-speed is often the preferred choice of many weekend club racers due to its high strength to weight ratio, as well as the fact that it can be had with an aggressive 0.82:1 overdrive ratio for exceptional pulling power down long straight-a-ways.  Conversely, if you have room in your budget and weight is not dominant concern, the Magnum offers similar features including a 5th gear ratio of 0.80:1 on some models, but with an additional overdrive for on-highway use, plus higher RPM shift capabilities and significantly greater torque capacity.

Q: How do I set driveline angles and why are they important?

A:  Having the proper driveline angles (see also pinion angle) is crucial to achieving a safe and vibration-free ride.  Furthermore, improper pinion angles can cause accelerated wear on a new transmission.

TREMEC offers a free downloadable Driveline Angle Finder App for smartphones.  Click here for more information and downloading instructions. Click here for instructions on how to use the app.

Q: How do I index the bellhousing, and why is it important?

A:  To say you have an improperly indexed bellhousing is also to say that your transmission is improperly aligned with the engine in front of it.  What this means is that the input shaft is not sitting true into the pilot bearing, which can cause a long list of transmission-related problems; as small as hard shifting or as big as total product failure. For more information, please contact a TREMEC Customer Service Representative.

Q: My transmission is hard to shift. What should I do?

A:  There are a variety of factors that can easily play into poor shift quality.  Typically they are related to a clutch or installation issue.  For more information, please contact a TREMEC Customer Service Representative.

Q: My transmission grinds when I attempt to change gears. What does this mean?

A:  The ‘clashing’ or ‘grinding’ of gears in a synchronized transmission are often related to one of three things: improper clutch actuation or adjustment, worn/damaged synchronizers, or the use of a fluid other than what is recommended by the manufacturer.

Q: My vehicle has a vibration that didn't exist prior to the installation of your transmission. Is there something wrong with the unit? How do I fix it?

A:  In nearly all cases, vibrations are the result of an oversight committed during the installation.  Items such as improper driveline angles, improperly indexed bellhousings, and/or issues related to the cross member or transmission mount can wreak havoc on an otherwise clean installation.

Sales & Service

Q: What is the warranty on a TREMEC transmission?

A:  All TREMEC transmissions come with a 12 month Limited Warranty from the original date of purchase.  Claims relating to damage incurred while racing, or under similar abusive conditions, will not be covered by the warranty. Read more.

Q: Where are TREMEC transmissions made?

A:  TREMEC transmissions are designed and manufactured in Queretaro, Mexico.  Marketing, sales, and customer support are located in Wixom, Michigan.  For more information about TREMEC and its facilities click on the “About Us” link on our website.  There you will see what markets TREMEC serves plus an overview of our facilities and capabilities.

Q: Who do I contact in the event that I have problem with a TREMEC transmission?

A: In many cases, the distributor you originally purchased your transmission from is best equipped to field questions regarding the unit.  This is due to the fact that many distributors modify our transmissions to meet specific needs or fit specific applications.  As an alternative, TREMEC’s Michigan-based customer service team is always ready to help, and can be reached using the information found on the Contact Us page.

Q: Does TREMEC offer sponsorships for racers and/or car builders?

A:  Yes, in limited amounts, and only after being approved by our motorsports panel.  To inquire about sponsorships, please contact us using the information found on the Contact Us page.

Q: I currently have an automatic, but would like to convert to a manual. Do you make conversion kits?

A:  No, but many of our distributors do.  To locate the distributor that best suits your needs please refer to our Distributor Search feature, or contact our customer service team using the “Contact Us” page.

Q: Can I buy transmissions or components directly from TREMEC?

A:  No, TREMEC does not sell directly to the public. Our network of authorized distributors can help you find the right transmission. For a list of domestic, Canadian and international distributors, please refer to our Distributor Locator, or contact Customer Service for a referral.

TREMEC Belgium team

To report an issue that you may have with your TREMEC transmission, please submit the form below.

Remember to add comments in the “Product Concern” field and upload photographs.

For general product inquiries, please contact our Customer Service team by phone at 1-800-401.9866, by email at, or by the Contact Us form.