Transmission Repair & Service Mount Forest, ON

Pinpointing the exact cause of any transmission problem takes skill, knowledge, and investigation

The evolution of transmissions has made these machines and systems increasingly complex. When transmission repairs are required, determining the cause and cure for what ails can be tricky. Why? Because transmissions have become remarkably complex and computerized and that presents both advantages and disadvantages. On one hand, transmission performance has become noticeably better in all vehicle makes and models. On the other, the increased complexity and digitization of transmission systems has made repair work a highly technical and complicated affair.


As you can imagine, there are different types of transmission repair jobs and options you can choose from depending on the nature of your vehicle’s breakdown. Understanding what those options are can help you make informed decisions when faced with a choice of transmission repairs to weigh.

A Repair for Every Type of Transmission Malfunction

Some transmission repair work is straightforward and mechanical in nature. Other times, it’s a combination of mechanical and electronic engineering that’s required to get your car back on the road. The most common types of repair work include:

  • Adjustments and in-car repairs. Most minor repairs are simple matters that are done without removing the transmission from the vehicle. If yours is a computer-controlled transmission that is not shifting properly, it is often the result of a computer sending incorrect signals due to a faulty sensor, or the transmission is not reacting to the command because of a bad connection or defective solenoid pack. If a non-computer controlled transmission is shifting too early or too late, it may require an adjustment to the throttle cable. If the vehicle has a vacuum modulator instead of a throttle cable, there is an adjustment that can be made using an adjustment screw in some designs. In vehicles with modulators, however, it is important to ensure there are no vacuum leaks and that the engine is running at peak efficiency.
  • Reseal jobs. A transmission is re-sealed to repair external transmission fluid leaks. If you see spots of red oil on the ground under the car, your transmission may need a re-seal job. To check a transmission for leaks, a technician will put the vehicle on a lift and examine the unit for signs of oil leaks. If a leak is spotted at any of the external seals or gaskets and the transmission otherwise performs well, the technician will most likely recommend that the transmission be re-sealed. Most of the external seals can be replaced while the transmission is still in the car but, if the front seal must be replaced, the transmission must first be removed from the vehicle to gain access to it.
  • Replacing accessible parts. There are a number of parts that are accessible without requiring the removal of the complete transmission. The parts that are accessible, however, vary from transmission to transmission and most transmission repair facilities would hesitate to provide meaningful warranties on external repairs for the simple reason that they cannot see if there are any additional internal problems in the components that are only accessible by transmission removal.
  • Complete overhauls. Also known as “rebuilding a transmission”, a complete overhaul involves the removal and disassembly of the transmission in its entirety. Every part is inspected for wear and damage, then cleaned in a special cleaning solution, or replaced with another part depending on its condition. Parts that have friction surfaces, such as bands and clutches are replaced as are all seals and gaskets. The torque converter is also replaced, usually with a remanufactured one. Technical service bulletins are checked to see if the auto manufacturer recommends any modifications to correct design defects that were discovered after the transmission was built. Automobile manufacturers often make upgrade kits available to transmission shops to resolve these design defects.

Replacing or Overhauling a Transmission

When a transmission requires an overhaul, there are two options that you may have. The first is to remove your existing transmission and overhaul it, then put the rebuilt unit back in your car. The second option is to replace your existing unit with another unit that has already been rebuilt or remanufactured.

A word to the wise: replacing your transmission with a used one may not be your best option. Used transmissions often have questionable histories that could create a whole new set of challenges. New transmissions, meanwhile, are mostly aftermarket transmissions billed as new but are in fact rebuilt transmissions with new parts.

The cost of the repair is always top-of-mind and understandably so. Transmission repairs are usually unexpected (and unwelcome). The cost varies depending on the outcome of our diagnostic testing, and we will help you to understand the various factors that come into play. We also offer our customers flexible payment options.

Whichever route you choose, you can trust our transmission experts to get you and your car back on the road.

Visit Mister Transmission for an assessment on what transmission repairs you may need. Contact the Mister Transmission service centre nearest to you.

Featured Services
Transmission Repair

The evolution of transmissions has made these machines and systems increasingly complex. When transmission repairs are required, determining the cause and cure for what ails can be tricky.

Learn More
Transmission Technology

At Mister Transmission we have access to leading-edge diagnostic equipment, enabling us to offer you the fastest and most accurate findings about what’s going on inside your vehicle’s transmission.

Learn More
Transmission Maintenance & Service

Just as you have other parts of your car serviced, your transmission needs maintenance to ensure a long life and avoid transmission problems.

Learn More
image-reviews image-reviews
Customer Reviews
Great, fast and easy
Holden DeGroot
Great, fast and easy
Date: March 6, 2026
Website: Google
Gary and his team are...
Emily Millie
Gary and his team are the best of the best! I had very little prior knowledge and was concerned about my car, so I randomly called to ask if they could inspect it. Even though I called an hour before closing, Gary was so kind, patient, informative, and generous with his time and knowledge, and he ensured I felt confident driving off the lot! I couldn’t recommend this place more, and I am very grateful for all they’ve helped with!
Date: February 24, 2026
Website: Google
I can’t say enough good...
DuDeK Master
I can’t say enough good things about this shop. I brought my car in fully expecting the transmission to be the problem because it was struggling badly to shift and barely accelerate. Instead of jumping straight to an expensive transmission repair, Gary took the time to properly diagnose the issue and was honest and upfront with me. He clearly explained that the transmission itself was not the problem and pointed me in the right direction, which likely saved me thousands of dollars! He was professional, knowledgeable, and didn’t try to upsell or pressure me into unnecessary work. He also took the time to write me a detailed email of the issues he found and also sent it to the other shop so I wouldn't have to explain it myself! That kind of honesty is rare and very much appreciated! When I showed up the next day to pay for the diagnostics and have my car towed to the other shop, he didn't even charge me! I would absolutely recommend this shop to anyone dealing with transmission concerns or who just wants straight answers.
Date: February 11, 2026
Website: Google
this place was amazing garry...
Matthew McCormick
this place was amazing garry fixed my transmission quickley at minimum cost if your having transmission problems dont wait come see them asap
Date: February 4, 2026
Website: Google
I recently visited to discuss...
A M
I recently visited to discuss some transmission issues with my Colorado, and Gary was absolutely fantastic. He was honest, knowledgeable, and saved me money by diagnosing the problem right away without needing a full diagnostic. Even though I live out of town and it made more sense to have the work done locally, he still took the time to clearly explain what was happening with my car. Service like that is rare these days. I honestly wish I lived closer so I could give him my business. Thank you, Gary — I’ll be recommending your location to anyone who needs service!
Date: January 21, 2026
Website: Google
Gary was fantastic to work...
Elijah Hiebert
Gary was fantastic to work with and had my truck fixed a lot faster than I expected. Definitely recommend Mr. Transmission for any transmission troubles you may have.
Date: September 22, 2025
Website: Google
Took my 2001 bmw to...
Thomas Lowles
Took my 2001 bmw to Mister Transmission for a shifting issue, Gary was great and easy to work with making an appointment. They communicated clearly with me on what they are working on the vehicle, quickly finding the issue. The part needed would have taken 4 weeks to arrive overseas so they fabricated a new one in-house to solve the issue! Highly recommend for any transmission issues to come here
Date: September 16, 2025
Website: Google
They did a great job...
Chris Bender
They did a great job and were very fast as well. I definitely recommend them.
Date: September 11, 2025
Website: Google
Gary and his team did...
Anne Facey
Gary and his team did amazing work on my car . I recommend this place . They are honest with the work and explained everything to me . If you need work on your transmission go here . I wish they had more stars I give them more stars instead of five stars .
Date: August 13, 2025
Website: Google
Reasonably priced and on time...
Nafis Hoq
Reasonably priced and on time service. Thanks Gary!
Date: July 25, 2025
Website: Google
Mister Transmission Blogs
Recent Blogs
Understanding GM 6L80 Transmission Codes...
If your GM 1500 has triggered a check engine light or is displaying
Read More
March 02, 2026
Transmission Replacement: When Your Vehi...
A full transmission replacement is one of the most significant services a vehicle may
Read More
February 27, 2026
Honda Transmission Repair: Understanding...
Honda transmissions are known for their smooth shifting, fuel efficiency, and long
Read More
February 20, 2026
Transmission Fluid Change: Benefits Of P...
Modern vehicles depend on advanced transmission systems that require proper care to
Read More
February 13, 2026
Transmission Shop: How Certified Technic...
A certified transmission shop gives drivers confidence because every repair is
Read More
February 06, 2026
Transmission Fluid Change: Why Preventat...
Transmission fluid plays a crucial role in the overall performance of your vehicle.
Read More
January 30, 2026
Dodge Transmission Repair: Symptoms Driv...
Dodge vehicles are known for their power, performance, and strong engines, but the
Read More
January 23, 2026
Ford Transmission Problems: Why Early Si...
Transmission problems in Ford vehicles rarely appear without warning. They begin as
Read More
January 15, 2026
Honda Transmission Replacement: Common W...
Honda vehicles are well known for their smooth performance, dependable engines, and
Read More
January 07, 2026
Transmission Rebuild Vs. Repair: Underst...
Your transmission plays a major role in how your vehicle performs on the road. It
Read More
December 31, 2025
Locations Served