Did you know that a valve body usually contains around two to four solenoids.
Both the asthma inhaler-looking solenoid and the ancient tablet-like valve body are inside your car’s automatic transmission which is why they are difficult to locate and repair. They speed up the transmission of car engine power to your wheels – faster than a car with manual transmission does.
How much, then, does replacing transmission pressure control solenoid cost? What about the transmission valve body replacement cost?
Transmission solenoid replacement is part of transmission services. The replacement service includes transmission shift solenoid which is not to be confused with a shift lock or interlock solenoid. This article, thus, will not include transmission shift lock solenoid repair details.
Repair and Replacement Costs
A shift lock solenoid replacement job can cost from $70 to $400 and can go as high as $480. This covers about $30 to $100 per hour of labor for the job that usually takes 2-4 hours to finish plus 3 to 5 quarts of transmission fluid that costs $6 to $10 a quart.
Additional costs might be expected to the quote since replacement parts will depend on the type and model of vehicle. This replacement job usually involves one or two solenoids. But there are times when the entire solenoid pack has to be bought.
Pack replacements can amount from $310 (Ford Focus) to $635 (BMW 330i), depending on the car model.
There are times, too, when replacing the solenoid is not enough and the entire valve body has become worn out or torn and has to be taken out. Transmission valve body replacement can be as low as $375 to as high $1,000, depending on your car’s model and type.
Whether you opt to do this D-I-Y or choose to go to a shop or mechanic repair, always check all the possible replacement parts your car will need, as well as their prices in various shops. Transmission solenoids, for example, may cost from $10 to $665, but it can get as low as $10 and as high as $1,000. Shift solenoids, on the other hand, can be as low as $10 and as high as $123.
Solenoid packs and valve bodies cost higher. A solenoid pack can cost as low as $310 and as high as $490. Their price depends on the brand, as well as the type of car they are meant for. Please take note that transmission and auto part dealers sell remanufactured solenoid packs and not brand new ones.
Valve bodies, on the other hand, can cost from $58.15 to $873, but their prices can also reach as high as $2,141. Variation in prices depends on the brand as well as the specific model of your car.
Transmission fluids are integral to the replacement process. In the market, transmission fluid can cost as low as $6 (1 quart) and as high as $378 (20 liters). Most transmission fluids cost lower than $10.
A transmission solenoid is difficult to locate and requires a proper device to ascertain whether it is the root cause of your gear shifting problems. It is for this reason that transmission solenoid replacement is handled mainly by transmission specialty shops.
Before you pop up another tab in your computer to look for one in your local map, you may wish to review first a few important points to ensure that you get the proper service by reading on.
Transmission Solenoid Basics
A transmission solenoid is an electro-mechanical piece; one that controls the flow of transmission fluid in your car’s transmission. It is considered a valve. Although in a valve body, it acts as the valve of valves. A car with automatic transmission usually makes use of a pack of solenoids for different purposes.
Each solenoid is an electromagnet, a spring-loaded plunger wrapped in a cylindrical coil of wire that is electrically charged in order to receive signals from the Electric Control Module (ECM) or Transmission Control Module (TCM) or generally the Transmission Control Unit (TCU) which is a sensor that will identify when to shift gears based on the car speed.
The TCU directs whether a solenoid should be open or closed. The solenoid, having received the signal, becomes a switch that interacts with other valves in order to create pathways for the transmission fluid. In return, the fluid exerts pressure on the bands and clutches that will push the transmission to shift gears. Once the solenoid stops receiving an electrical signal, its plunger will then close.
The transmission solenoid is actually part of a complex system of pathways called the transmission valve body. The valve body looks like a maze made of metal – it is composed of routes and channels which the transmission fluid passes through to reach the valves that will allow the proper combination of clutch activation and gear shifting.
There are two types of valve body:
- The Electronically Controlled Transmission (ECT) is the valve body used by modern cars with automatic transmission. The ECT utilizes solenoids that make elaborate and complex task performances possible. Some of these tasks include vehicle and engine speed monitoring, throttle position checks, and antilock brake system.
- The Hydraulic Valve Body, on the other hand, is a basic structure that allows the fundamental functions of an automatic transmission possible by manually regulating the valves in controlling the movement of the hydraulic fluid.
Solenoid Malfunction and Symptoms
There are two possible root causes for a malfunctioning solenoid – fluid contamination or electrical problems.
Contamination of your car’s transmission fluid can lead to a stuck solenoid. There may be some wayward elements or components carried by the transmission fluid that got between the TCU and the solenoid which would cut off the signal. The sludge in your car’s transmission fluid could also have plugged the valve body itself, which keeps your valves from functioning properly.
Electrical problems are the second root cause that solenoids malfunction. Bad connections, a shorted out solenoid coil or even a frayed wire could keep your solenoid from working.
When your car’s solenoid stops working, your car will manifest this problem in any of the following:
- Slippery shifting – Ideally, shifting gears should be smooth, reflective of how your transmission is also working properly. A malfunctioning solenoid will cause excessive hydraulic pressure from the transmission fluid, causing you to find shifting gears a slippery or rough task.
- Gear shift delay – as mentioned above, electrical signals between the TCU, the valve body, and the clutch, speed up the reaction time of your clutches that controls the gear shift. If you happen to experience some lag time whenever you change gears, then this means somewhere along the way between the TCU and the clutch, something went wrong – and that something could highly be your faulty solenoid.
- Sudden Gear Shift – does your car suddenly jump to upper gears, skip some gears when you accelerate, and even refuse to lower gears? If such is the case, you may have a problematic solenoid in your transmission. A normally working transmission solenoid will shift gears up when you speed up and will automatically lower gears when you slow your car down.
- Absence of Gear Change – difficulties in gear change; even to the point of no shifts could mean that it is not just one solenoid that is not working. It could either be the whole solenoid pack or even the valve body.
- Locking at 2nd or 3rd gear at maximum speed – a totally-malfunctioned transmission solenoid tends to cause an open circuit within your transmission electrical system. When this happens, your car shows a symptom called Fail Safe or Limp Mode, which is characterized by its locking at 2nd or 3rd gear when you try to achieve maximum speed.
At Fail Safe, your car needs to be reduced to 30mph. Otherwise, the transmission will overheat and your car is in danger of any transmission failure mid-drive which would endanger you, too. When limp mode happens, it is, therefore, better to drive slowly and have your car fixed right away.
When you experience on your car the symptoms mentioned above, the first thing you need to note is whether the check engine indicator light is on and whether you are experiencing noise when you try to shift gears. Experiencing any of the above symptoms could be caused by electrical malfunction rather than the solenoid itself. But if the check engine indicator light is switched on, this definitely means that your car has a faulty transmission solenoid.
Another thing you may need to check is whether you hear any noise when you try to shift gears aside from any of the symptoms that have already been mentioned. Noises made in gear shift could mean an increase in hydraulic pressure in your valve body which could mean many possibilities – including a grimy transmission fluid that needs to be replaced, a clogged valve body, and a stuck solenoid.
The best way to determine whether you have a malfunctioning solenoid and valve body, however, is still through proper diagnosis. Experienced mechanics will test your car using On-Board Diagnostics II (OBD2) reader, which will determine the status of your car’s valve body and transmission solenoid.
The Replacement Process
Replacement of transmission solenoid requires proper tools such as an OBD2 reader, as well as a deep knowledge of transmissions and their internal parts. Because of this, it is better to leave the repair to an experienced mechanic or a well-trusted auto repair shop that also handles transmission services or a transmission specialist shop.
The first thing your car undergoes during repair is a proper diagnosis using the OBD2 reader. Once the transmission solenoid or valve body problem has been reaffirmed and confirmed, the first thing that is done when the mechanic gets to the transmission is the draining of the transmission fluid, the detaching of the transmission tank, and the disconnection of wires of the solenoid. The drained fluid will then be checked if the problem possibly has to do with debris or clogging, while the transmission tank will also be checked for any problems.
If the transmission tank is considered clear and only the valve body, solenoid or solenoid pack is faulty, rebuilding then resumes. The new solenoid, solenoid pack or valve body is installed in place of the old one, then the transmission is returned in place and the wires reconnected. The transmission fluid tank is then returned before the tank is refilled with transmission fluid.
When repairs and reinstallations have been completed, the mechanic will clear all the error codes with the OBD2, before your car is subjected to a test drive.
Things to Note: Repair Cost Savings Tips
As mentioned above, for such a 1-2-inch sized component like a malfunctioning solenoid that can be quite challenging to locate, repair costs go beyond $100. While some transmission specialist shops may propose a way to save or some payment system to reduce the load, you still may wish to go D-I-Y or source the materials yourself.
If you opt to D-I-Y, make sure to have all the car and transmission properly diagnosed first, especially if you plan to replace the solenoid on your own car. The same mechanic will also have to clear those codes.
Mind, however, that some mechanic or shop might ask you to let them dismantle or work on your car to do a proper diagnosis. Beware of these types, as they might charge you for such a dismantling job and you will be forced to cough up bucks and maybe even subject your car to them for repair.
Always do your research regarding prices of replacement parts, the labor, and all the other fees required for a solenoid, solenoid pack, or a valve body replacement service. You can even do research on the competitor’s price, reputation, and handling repairs.
If you opt to have your car undergo professional repair, take note that dealerships are trained to recognize problems and to perform external repairs, but not transmission repairs. They may be able to help in D-I-Y during diagnosis and clearing errors, but not in the fixing.
The best option there is for professional help would be to go for transmission specialist shops or highly reputable mechanics who have experienced working in such shops. Check the shop’s or the mechanic’s background. Do they have a history of fly-by-night practices? Better yet, be mindful of referrals and warnings from customers and mechanics who have worked with them.
When asking for an estimate, do not hesitate to ask for definite prices – ask for the roof price or the price of the service you have to pay in case there is a “worst-case scenario.” You may even ask them what that could be – just avoid mentioning your expected worst case, as an unsavory shop might take advantage of this. Just to stay safe, ask for a second opinion.
Always ask for well-defined warranties. Check if there are possible loopholes – some shops tend to ride on these loopholes aside from giving your car a botched job.
Additionally, and when you have finally chosen a repair shop or mechanic, ask them to show the broken parts they replaced – this may not be too fool-proof, but this reduces the possibilities of cheating you of your hard-earned money.
There are still many other ways to ensure that you are given the right service. The important thing to remember is that a low repair price is not always everything – trust is.