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What are transmission solenoids?

Solenoids are electro-hydraulic valves that control the flow of transmission fluid needed to change gears, opening and closing in response to the electrical signals they receive from your vehicle’s engine or transmission control unit, which pulls its data from a series of speed sensors in the engine. It is the flow of transmission fluid, which is controlled by the solenoid valves, that pressurizes your transmission’s clutches and bands, facilitating gear changes.

In automatic transmissions, transmission fluid is directed through the valve body by several types of solenoids, including:

• The transmission shift solenoid
• The lockup solenoid
• The transmission control solenoid
• The torque converter clutch solenoid

Manual transmissions do not typically have shift solenoids. Instead, they use the manual clutch to control how and when gears shift.

The solenoid body itself is generally constructed from steel and designed in a cylindrical shape, with a valve and return spring. The solenoid coil consists of a wire wound around a conductive component that acts as an electromagnet. Though they vary in design, most transmission solenoids comprise the following nine parts:

• Valve body
• Inlet port
• Outlet port
• Solenoid coil body
• Coil winding
• Lead wires
• Plunger or piston
• Spring
• Orifice

If any of these parts fail, your solenoids stop working, and your transmission stops performing.

Why do transmission solenoids fail?

Common causes of transmission solenoid failure include:

• Electrical issues (e.g. applying incorrect voltage to the coil)
• Dirty transmission fluid, which may cause the shift solenoid to become stuck open or closed
• Wear and tear—like any mechanical device or component, solenoids can simply wear out over time, although preventative maintenance can offset or reduce wear and extend the service life of your solenoids

If you suspect that one or more transmission solenoids have gone bad, get in touch with a Mister Transmission near you, and we will help you pinpoint and repair the problem, fast.

When to book a transmission service: 7 signs of solenoid failure

Plenty of transmission shifting problems can be traced back to a malfunctioning shift solenoid, including:

1. Delayed or unpredictable gear shifting. If you experience a delay in shifting, or your vehicle has ever jumped to another gear on its own, there is a very good chance that one or more solenoids are failing.
2. Skipping gears. If your vehicle has problems engaging certain gears, and it tends to skip over the “problem gear” whenever you attempt it, there’s a good chance that specific solenoid is broken or worn out.
3. Getting stuck in certain gears. If your shift solenoid was damaged while a gear was engaged, it might cause the transmission to end up stuck in that gear.
4. Vehicle sluggishness. Does your vehicle seem a bit sluggish or slower than usual? In response to solenoid failures, some vehicles engage Limp Mode, a protective function for your engine that caps RPM at 2500-3000, limits shifting, and keeps you under third gear. If your vehicle has engaged this protective mode, you’re probably dealing with a solenoid issue.
5. Inability to downshift/upshift. In many cases, solenoid problems make shifting difficult. Sometimes the transmission will be able to move upward from gear to gear without a problem, but it will be unable to shift back down. This generally occurs when the solenoid has become stuck in an open orientation, perhaps due to physical damage to the solenoid body, wiring issues, or dirty fluid leaving foreign matter that prevents the solenoid from shifting into position.
6. Check Engine light / transmission warning light. Some modern vehicles come with dashboard indicators that alert drivers to solenoid/transmission issues. If you have an OBD-II code reader, or you drop by your local Mister Transmission for a diagnostics test, you may also see a P0700 code, which indicates that there’s a malfunction with your Transmission Control Module. However, P0700 codes may also indicate problems with transmission fluid levels, broken wires between TCM and ECM, and more. For a concrete diagnosis and cost-effective repair, get in touch with your local Mister Transmission.
7. Engine continues to rev when applying the brakes. If your tachometer needle keeps climbing as you hit the brakes, there’s a good chance you have a faulty solenoid.

What does it cost to repair/replace transmission solenoids?

Depending on the make, model, and year of your vehicle, transmission solenoid replacement costs can vary. In general, a single faulty transmission solenoid replacement costs approximately $250. Replacing the entire solenoid pack can cost around $400.

As you can see, replacements are often costly, so you want to make sure that you do not replace a functional shift solenoid. To that end, we offer 100% free road tests and multi-check inspections to help you get to the root of the problem, maintain your vehicle’s performance for longer, and pay only for the services you need. To book your free battery of tests, get in touch with your local Mister Transmission.

Book a transmission solenoid repair/replacement at Mister Transmission

For more than 58 years, Mister Transmission has been a leading provider of solenoid maintenance, repair and replacement services across Canada. To date, we’ve helped thousands of Canadians keep their transmission solenoids in-shape, and we can do the same for you.

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

And no matter which location works for you, you’re guaranteed:

• A history of success—Our commitment to customer care and superior service is borne out by 58+ years of success and over 11,000+ glowing reviews.
• Leading transmission technology—We equip our highly trained transmission specialists with high-quality tools and leading diagnostic technology to get you great results on every service.
• Flexible payment plans and customer rewards—We offer flexible payment plans and give away $1000 worth of transmission repair services every month, so you can keep your transmission solenoids in shape without breaking the bank.
• Nationwide warranty—We stand behind our transmission repair, maintenance, and replacement services with one of Canada’s best warranties.

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