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What is a torque converter and how does it affect my transmission?

The torque converter is a critical and complex part of your automobile that transfers the engine’s power to the transmission.

Technically speaking, the torque converter is a kind of fluid coupling, known as hydraulic coupling, that basically acts as an alternative to the mechanical clutch found in manual transmissions.

When they are in proper working condition, torque converters multiply torque at lower RPM, which allows for more power to be generated than would be possible through simple fluid coupling.

Torque converters have 3 basic stages of operating:

1. Phase 1 — Stalling: When you’re braking at a red light or a stop sign and your engine is still running, it applies power to the impeller, which rotates independently, without coupling with the turbine.
2. Phase 2 — Acceleration: When the red light turns green and you step on the gas, the impeller rotates at high speeds, and because the turbine rotates more slowly, torque multiplication is produced.
3. Phase 3 — Coupling: When your vehicle starts moving fast, the turbine rotates at about 90% of the impeller speed, causing torque multiplication. At this point, the lock-up clutch locks the turbine to the impeller, providing greater efficiency and preventing any slippage.

The torque converter is found between the engine’s flex plate and the transmission, comprising the following different parts:

• Impeller—The impeller is a component designed with curved blades and filled with fluid. When its blades spin, the impeller casts fluid using centrifugal force, and the faster it rotates, the more fluid is forced outwards, transmitting energy to the turbine.
• Turbine—Situated opposite the impeller and designed with the same curved blades, the turbine receives fluid from the impeller, rotating as fluid flows against its blades, then trading it back and forth, transmitting rotating mechanical power through the process known as fluid coupling.
• Stator—This part is interposed between the impeller and turbine, where it receives fluid and turns the fluid flow at almost a 90-degree angle, causing a multiplication of torque.
• Housing—The impeller is mounted to the torque converter housing, which is connected to the engine.
• Turbine output shaft—The turbine output shaft connects the turbine to the transmission and wheels of the vehicle.

Should any of these parts fail, your torque converter will too!

How to detect a torque converter failure: Top-6 signs of trouble

1. Loss of acceleration
2. Slipping between gears
3. Vehicle refuses to shift
4. Transmission is overheating
5. Transmission fluid is leaking
6. Transmission fluid contamination

If you detect any of these problems, you should contact your local Mister Transmission for a 100% free road test and multi-check inspection, which includes:

• Visual inspection
• Fluid Check (on models with dipsticks)
• Road Test
• On Board Diagnostics (OBD) Computer Scan – read codes

After we’ve completed these preliminary tests, a torque converter specialist will rule out any problems with the following components (additional charges may apply):

• Neutral switch
• Engine RPM
• Throttle linkage
• Modulators
• Transmission mounts
• U-joints
• Fluid retention
• Electronic controls

Whatever problems we detect, our torque converter technicians will help you solve them. We offer everything from minor repairs and simple part replacements to complete overhauls, and we make sure our technicians only use the best brand-name equipment, tools, and diagnostic technology, so you can avoid the hassle and expense associated with a bad repair service.

How to avoid a bad torque converter repair: 4 signs of poor service

1. Poor acceleration—If your vehicle struggles to accelerate after your torque converter service, it may be possible that the stall range is not properly matched to the camshaft RPM range. As a rule of thumb, the stall speed should be approximately 500 RPM higher than the starting RPM of the cam. Make sure to factor in the weight of your vehicle when selecting these specifications.
2. Converter fits too tightly against the flexplate—If this is the case, your repair technician may not have seated the torque converter properly on the input shaft of the transmission. You should feel 3 clicks of engagement, the third being the pump drive. You may need to remove the transmission and reinstall the torque converter.
3. Converter won’t engage on the input shaft—Try working the converter up and down on the input shaft, spinning it gently in the process. Smaller converters can be harder to install because there is less room for internal parts to move, so make sure you select the right size.
4. Premature wear or torque converter failure—If you choose a high stall converter to go with a numerically low gear, it can overheat and fail. It is also not recommended that you install a torque converter on a transmission that has previously failed, since debris from the damaged transmission can travel through the converter and damage it.

For best results, the Mister Transmission team reminds you to:

• Use only premium quality parts
• Take a pre-measurement to ensure proper engagement of your new torque converter
• Add one quarter of transmission fluid to pre-lube the bearing inside your new torque converter
• Replace the transmission filter at the same time
• Inspect the flexplate thoroughly to ensure adequate room remains
• Lubricate as necessary—apply transmission fluid to the front seal and grease to the pilot of the torque converter before it is installed

Go pro: Book a quality torque converter repair service

For more than five decades, Mister Transmission has been a leading provider of torque converter maintenance, repairs, and replacements for drivers all across Canada.

When you choose our team for your torque converter service, you get:

• One-stop shop convenience, with all the parts and services you need under one roof.
• Peace of mind, with the quality of our services borne out by 58 years of success and over 11,000+ glowing reviews.
• Cutting edge tools and technology, including brand-name parts, diagnostic technology, and tools.
• The best warranty in Canada, available as a Standard (12 months / 20,000km) and Premium (36 months / 60,000km) package.
• A chance to win a free repair, with $1000 in service fees given away each month as part of the Win Your Repair Program.
• Budget-friendly payment options, as described in our Flexible Payment Plan.

For your convenience, we offer:

• 42 locations in Ontario
• 3 locations in Alberta
• 5 locations in British Columbia
• 2 locations in Manitoba
• 2 locations in Quebec
• 1 location in New Brunswick
• 1 location in Nova Scotia

To book a free road test and multi-check inspection, you can use the Mister Transmission Finder to connect with a torque converter expert near you.