Modern automatic transmissions use pressurized hydraulic fluid to change gears. Every time a gear change is required, the car’s computer activates a transmission solenoid, which directs transmission fluid into the valve body to engage the correct gear. If one of these electro-mechanical valves fail, then all sorts of transmission problems can ensue. So let’s take a closer look at the shift solenoid, and the common problems associated with it.
What Transmission Do I Have?
How Does a Transmission Solenoid Work?
As you’re going down the road, the car’s computer analyzes data being sent by vehicle speed sensors and engine speed sensors. Based on this information, the Engine Control Unit (ECU), or the Transmission Control Unit (TCM), executes the appropriate upshift / downshift by sending a signal to one of several shift solenoids. These transmission solenoids have a spring-loaded plunger inside, which are wrapped with wire. When this coil of wire receives an electrical charge from the TCM / ECU, it causes the plunger to open, allowing transmission fluid to flow into the valve body and pressurize the desired clutches and bands. When this happens, the transmission changes gears and you continue down the road.
The car’s computer can control the transmission solenoid in several ways. If the vehicle is equipped with a dedicated Transmission Control Unit, it can open or close the hydraulic circuit using a direct 12v signal. Or, the Engine Control Unit can control the solenoid’s plunger by turning the ground circuit on and off. A solenoid can be used to control a single gear or multiple gears, depending upon the complexity of the design.
Symptoms of a Transmission Solenoid Problem
A transmission solenoid can fail due to electrical issues, or dirty fluid that’s caused the shift solenoid to become stuck open / closed. Any change in the transmission fluid pressure can cause numerous problems, including:
Erratic Shifting – If you’re dealing with a failed transmission solenoid, the gearbox can skip a gear up or down, shift back and forth between gears repeatedly, or get stuck in a gear and refuse to shift.
Transmission Won’t Downshift – If the transmission will not downshift, one of the shift solenoids may have become stuck open / closed, preventing fluid from entering the transmission valve body to pressurize the correct gear.
Severe Shifting Delay / Stuck in Neutral – In order for an electronically controlled automatic transmission to shift gears, the solenoid must be able to regulate the fluid pressure to activate the appropriate gear. If the shift solenoid is receiving too much or too little electric current, or dirty transmission fluid has caused it to become stuck open / closed, gear engagement maybe become difficult or delayed, which can cause the transmission to act as if it is temporarily locked in neutral.
Because the solenoids are connected to a vehicle’s electrical system, the ECU will usually register an error code and trigger the check engine light if something goes wrong. If this happens, the transmission can go into limp / fail mode, where it will only engage second / third gear to limit the vehicle speed without immobilizing it.
The first thing that your mechanic should look at are the error codes. Using a scan tool, the technician can determine the source of the solenoid’s problem. It could be as simple as a bad ground, or as complex as a failed solenoid pack (a grouping of individual shift solenoids).
Transmission Solenoid Replacement Cost – Parts & Labor
In most cases, solenoids are located inside of the oil pan, connected to the valve body. Depending on what you drive, the technician may be able to replace just the failed shift solenoid. However in some cases, the solenoids come in these multiple unit packs so if there is a problem with one, the entire pack must be replaced. This job typically takes 2-4 hours to complete, and shop time is generally billed at $60 – $100 per hour. The average total cost to diagnose and replace one ranges between $150 and $400.
Depending on the make and model of your vehicle, expect to pay between $15 – $100 for a single transmission shift solenoid. A pack can cost $50 to $300.
| Type | Cost Range |
|---|---|
| Single | $15 to $100 |
| Pack | $50 to $300 |
| Labor | $120 to $400 |
| Total (Pack) | $250 to $600 |
Although it isn’t unusual for transmission shift solenoids to wear out over time, you can extend their life by changing your transmission fluid at the factory recommended intervals. This will clean out all of the dirt and sludge that builds up, and the fresh fluid will keep the plungers on the inside of the solenoids from sticking. If you don’t know what your vehicle’s recommended transmission service intervals are, check the back of your owner’s manual, or simply ask Google.
Get a great deal on a replacement solenoid – for as low as $11 on Amazon <
Need a replacement transmission? Get an estimate for replacement transmissions and local installation. Look up your transmission model by vehicle make and model.
What Transmission Do I Have?
Takes off in 3rd gear but shifts to fourth. Wont downshift. 94 4l80e transmission
2008 Impala 3.5l tranny shifts hard when hot in bumper to bumper traffic 1st-2nd gears
Won’t shift out of first gear 2000 Nissan frontier 2.4 auto
I have a 2006 clk500 Mercedes and it’s stuck in either limp mode or my solenoids can possibly be messed up or the fluid is dirty the car revs and has all the power the gears just won’t shift
1974 Ford f600 was driving the truck and then it lost power the Driveline turns but the very end won’t engage must be a solenoid
I got a town and country 2012 got a trouble code for shift solenoid and it went into limpmode had to get to work on the way there it stop so I was wondering do I need new trans or can still change the solenoids?
Shift solenoid stuck , code P0700
2005f1504x4 noforward notslipping oilandfilternew reverseok
I have a 2003 Mitsubishi Lancer ES automatic transmission..started out with RPM’S high at freeway speeds..Scanned it with OBD2 and pulled a 715..Input speed shaft sensor..replaced it twice and it’s no better. Cleared the code and came back 715 AND 340 trouble codes..I don’t know if I should just wash it with gasoline and dry it with a match or what. I’m trying to do this on my own but struggling as I don’t know a huge amount about cars..Can anyone suggest anything that could b contributing to those the two trouble codes??
I’ve change my transmission oil and filter I noticed in my transmission pan on the magnet a build up of gray gunk with fine metal shavings hoping this would fix my slipping problem making my rpms shoot up there and having to stop then go again and let it shift out again in my 2015 GMC Sierra 1500 5.3 truck
no reverse in Cadillac Escalade all gears work otherwise
05 Tacoma not shifting out of 3rd, then feels like I’m in Neutral for a bit, until it’s had a chance to slow down & downshift. It will shift all gears IF put in 2nd then once in 3rd, let it rev to around 3500rpms & shift it into drive. It had a. Check engine light but, not anymore. Ty
My 05 trailblazer has an issue after starting i can go forward and reverse then after a bit .it goes to neutral engine races but goes noplace ….need to find out what the issue is
Me too what is the problwm?
The time after I start it goes and works fine however when I pull in to park it it sails into neutral no gear at all
Hi I have a 2008 mini copper clubman S. I’m wondering if I can just change the solenoids instead of the whole transmission valve body. My doesn’t go into 4th gear and I’m sure it’s the solenoids, but just want to make sure that it’s OK for me to just replace that and not have to replace the whole valve body
as long as its not to old that should be the right fic for what it sounds like
Why can’t I feel my car shift when accelerating? Should I be alarmed
I have an 08 Chevy Colorado. I initially had clutch issues, got those fixed, now I can shift in & out gear no problem, but when I left off clutch, nothing. I can even let off clutch stopped in gear & it won’t kill it. I took shifter off & looked down in it & it looked dry, so I addy 1 qt of fluid. I can kinda get it moving now. But any bit of a hill & it’s done. Any suggestions!?!?!
Transmission downshifts at about 45 to 50
2005 ford explorer code p0745, replace solenoid pack and still getting p0745. any suggestions on what could be wrong.
Engine stalls when put in reverse after warm up. Car starts back after stalls
When putting into reverse engine locks up. I can work the gas pedal and get it going and. It is fine as long as left in reverse. It is now happening in drive.
2004 Chevy suburban 1500 4×4. Hesitates shifting into second gear until I let off the throttle .. does not down shift.. cruise control does work .. fluid is good .. 4L60e transmission.. what would the problem be ?