Torque converter problems are sometimes misinterpreted as symptoms of a failing transmission. Unfortunately, this can lead people to think that they need to spend thousands of dollars to rebuild or replace their automatic transmission when the cost to replace a malfunctioning torque converter is considerably cheaper.
What Transmission Do I Have?
A local auto repair shop will be able to determine whether or not the problem lies in the transmission itself or the torque converter. Finding a reputable shop is very important because as we have mentioned, the symptoms can be very similar and a transmission replacement is considerably more expensive.
In This Guide:
- What Does a Torque Converter Do?
- 6 Signs of Torque Converter Problems
- How to Diagnose the Problem
- Causes of Torque Converter Issues
- Replacement Cost
However, diagnosing the cause of a transmission issue isn’t easy. In many cases, the torque converter will not actually be the source of the problem (you might just have a fluid leak!). The purpose of this guide is to simply help you narrow down the possibilities and educate yourself before you get your transmission checked out.
What Does a Torque Converter Do?
In a nutshell, a torque converter is a fluid coupling that transfers torque from the engine to the transmission. It is mounted between the engine and transmission, bolted directly to a ‘flex plate’ which is spun by the crankshaft.
Internal combustion engines create power by burning fuel that forces the pistons to turn the crankshaft located at the bottom of the engine. This rotational force is transferred to the transmission by the fluid pressure inside the torque converter.
Inside of the torque converter cover lives a series of propeller-like blades called the pump. This assembly spins in unison with the engine crankshaft, forcing transmission fluid onto another blade assembly called the impeller. This second set of blades is connected to the transmission input shaft. The amount of hydraulic pressure that it creates inside the transmission dictates the gear and ultimately, the speed of the vehicle.
The impeller’s speed is regulated by the engine side of this hydrodynamic circuit (ie. speed of the pump blades). When the vehicle is stationary, or the driver applies the brakes, the impeller will slow considerably, while the pump continues to spin. This allows the torque converter to act like the clutch in a manual transmission – it allows the engine to continue running while the vehicle is at a complete stop.
Once the transmission fluid has been hurled onto the impeller blades, it has to return to the pump in order to keep the cycle going. Since the fluid is now flowing in a different direction than the pump, it has to be reversed to avoid slowing down (and stalling) the engine.
To do this, a third finned wheel called the stator is located between the two turbines on the transmission pump shaft. Its blades are precisely angled so that when the transmission fluid hits them, it reverses direction and gets channeled back to the pump. When the vehicle stops, its built-in one-way clutch causes it to stop spinning, breaking the hydrodynamic circuit.
Once the vehicle starts to accelerate from a stop, the stator is once again free to spin. In the split second that the transmission fluid hits the back of the now-released stator, it starts to spin the transmission pump, and briefly multiplies the torque coming from the engine side of the circuit. This causes the transmission pump to force more fluid in the transmission, resulting in movement.
Once the vehicle is in motion, the stator’s one-way clutch allows it to start spinning in the same direction as the other turbines, reversing the fluid flow and completing the hydrodynamic circuit.
After all of the transmission gears have been shifted through and the vehicle has reached cruising speed, the lockup clutch engages, connecting the front cover of the torque converter (aka the pump) to the impeller. This causes all of the turbines to work together in a direct drive/overdrive scenario.
6 Signs of Torque Converter Problems
It isn’t easy to isolate and diagnose a torque converter issue without taking the transmission/drivetrain apart, but there are several symptoms to look for. A few of the signs of a malfunctioning torque converter include: shuddering, contaminated fluid, gears change at high RPMs and strange sounds such as clicking or whirring.
Slipping
Since a torque converter is responsible for translating engine torque into the hydraulic pressure needed to shift gears inside the transmission, a damaged fin or bearing can cause the transmission to delay a shift, or slip out of gear.
Slipping can also be caused by there being not enough or too much fluid in the transmission. You may also experience a loss of acceleration and a noticeable reduction in your car’s fuel economy.
Be sure to check your fluid levels before taking your car to a shop.
Overheating
If the temperature gauge indicates that your car is overheating, it could be a sign that there has been a drop in fluid pressure and there is a problem with your torque converter. If a converter is overheating, it won’t be able to transfer power from the engine to the transmission. This results in poor throttle response, and excessive wear and tear on the internal workings of the transmission.
Low fluid levels or a malfunctioning solenoid can also cause a transmission to overheat.
Shuddering
If the lockup clutch inside the torque converter is starting to malfunction, you may experience shuddering at around 30-45 mph. The sensation is very noticeable and typically feels like you’re driving over a rough road with many small bumps. As the converter switches over to direct drive, a worn lockup clutch can make the transition difficult, resulting in this sensation. The feeling may start and stop abruptly and may not last long, but if you’ve experienced it several times, it’s time to get your transmission checked.
Contaminated Transmission Fluid
A torque converter is filled with automatic transmission fluid (ATF). If the fluid is contaminated, it can do damage the parts inside. This can result in worn bearings on the stator, or damaged fins on one of the turbines.
If you notice a significant amount of black sludge/grime/debris in the fluid it could mean that the converter or transmission itself is damaged. In this case, change the fluid and drive around for a while before checking the fluid again. If the problem persists, get your car checked by a professional.
Higher Stall Speed/Gear Engagement RPM
The ‘stall speed’ is the point at which the engine RPMs are high enough for the torque converter to transfer power from the engine to the transmission. In other words, it is the RPM at which the converter will stop the engine speed from increasing if transmission output is prohibited.
If the torque converter is broken, it won’t be able to transfer the engine’s rotational force into hydraulic pressure correctly. This will result in the transmission taking longer to engage the engine, causing the stall speed to increase. Here is how to do a stall speed test. You’ll have to find out what your vehicles stall speed is beforehand (typically 2000 to 2500 RPM).
Strange/Unusual Sounds
It’s not uncommon for the torque converter to emit strange noises as it begins to fail. Some of the sounds you might hear include a ‘whirring’ sound coming from bad bearings, or ‘clinking’ sound coming from a broken turbine fin.
How to Diagnose the Problem
Here is how you can try diagnose the problem yourself. At each step, listen carefully for unusual slipping, shuddering, lurching forward or strange noises:
- Start your car and let it run for a couple minutes
- Press the gas down lightly several times
- Push the brake and shift the car into drive
- Slowly shift through each gear
- Drive around the block, listening carefully every time you accelerate
Do Not Drive With a Broken Converter
Important to note – a converter can slowly fail over the course of several weeks or even months before it completely breaks down. Driving a vehicle with one that is damaged can be risky as it can completely disintegrate when it breaks down – adding metal debris into the transmission fluid. The contaminated transmission fluid can then make its way into the transmission and cause significant damage or even complete failure, turning what could have been a simple converter replacement into an expensive transmission repair or replacement. To prevent this, pull off the road when it is safe to do so and shut off the engine.
Common Causes of Torque Converter Problems
There are a few reasons why problems can occur. Don’t assume what the problem is until you have your transmission looked at, but here are some general ideas of what it could be.
Bad Torque Converter Needle Bearings
The impeller, turbine and stator use needle bearings in order to turn freely. The bearings separate these rotating components from the converter housing. If these bearings are damaged, you’ll notice reduced power, strange noises and bits of metal in the transmission fluid due to metal on metal contact/grinding.
Damaged Torque Converter Seals
If you notice a transmission fluid leak coming from the bell housing, then you might have a damaged torque converter seal. If your torque converter can’t hold the proper amount of ATF, then it won’t be able to transfer power from the engine to the transmission effectively. This will result in overheating, shifting problems, strange noises, higher stall speeds, and slipping between the gears. The bad seal will need to be found and replaced.
Worn Torque Converter Clutch
Automatic transmissions have a number of clutches located throughout the assembly. A torque converter clutch is responsible for locking the engine and transmission into direct drive.
If the torque converter has been burned by overheating, become jammed/locked up due to distortion or contaminants in the transmission fluid have damaged the friction material on it, then your car may stay in gear even though you come to a stop. The converter can also shake and not lock itself into direct drive if the friction material on the clutch plate has worn away.
Faulty Torque Converter Clutch Solenoid
A torque converter clutch solenoid regulates the amount of transmission fluid that the converter’s lockup clutch receives. If this electronic device can’t accurately meter the fluid pressure, then the lockup clutch will not work properly as a result of too much or too little fluid supply. This can result in loss of the direct drive function, poor gas mileage and engine stalling.
Torque Converter Replacement Cost
If you’ve noticed one or more of the above symptoms, then it’s possible that your torque converter is malfunctioning. The cost of getting it repaired can be higher than simply replacing it, so be sure to have a mechanic/technician take a look.
| Repair | Cost Range |
|---|---|
| DIY | $150 to $500 |
| Transmission Shop | $600 to $1000 |
If you plan to do the work yourself, then you’ll be looking at a repair cost between $150 and $500.
Repair shops will charge between $600 and $1000 to replace a torque converter.
The torque converter itself is relatively inexpensive (between $150 and $350, depending on the vehicle), but 5-10 hours of labor is involved since the transmission must be removed in order to replace the torque converter.
The fluid should also be flushed/changed at the same time, which may or may not be included in the price a shop gives you.
What Transmission Do I Have?
Over to You
What problem do you think your torque converter has? What symptoms is your car experiencing?
I just changed my transmission out of my F-150 XLT 4.6 I took the transmission out of a 98 f250 I replaced everything drive shaft torque converter everything out of the 250 into my 150 now when I accelerate it shutters and sputters like it’s not getting gas I was thinking about putting the F-150 torque converter back in it and trying that out any help
Well when you first start the truck and put it in gear sometimes it slips it won’t go in gear you can feel it and then it’ll catch and take off but it’s kind of dragging or bogging down I guess but if you shut it off and start it again it’ll kick right into gear and take off like there’s no problem it’s a 2005 ram 1500 4×4
It runs in high rpms doesnt shift gears properly makes a whinning sound when your speed reaches 50 mph drives great speed and all but the whinning is unbareabke
I’m hearing a humming from 0 to about 15 miles per hour and the the noise stops. I felt it slip once besides that it drives and shifts fine I’m guessing that it’s the torque converter
While driving/accelerating at about 25 mph it comes completely out or gear.
2014 Jeep Compass with 6 speed transmission. Driving 20 – 30 MPH between 2K & 2.5K RPM’S a shudder/vibration heard on lower left side engine bay in front of driver & felt in gas pedal too. Sensors on dashboard do not light up & gears seem to shift normally with occasional need to accelerate harder than usual to increase velocity which makes shudder/vibration go away. Does not occur at all when decelerating. It occasionally doesn’t happen when accelerating too. Tends to come & go. Dealership says it’s due to movement between exhaust manifold & connecting exhaust pipe that has some play causing slight exhaust leak which’s reason why ot comes & goes but I think they can’t locate it or just don’t want to take time to repair thinking I’ll simply purchase a new vehicle when I tire of issue. Transmission mechanic says it’s not torque converter or transmission at all. Not sure if he’s waiting for issue to get worse & cash in on a larger & more expensive repair. Torque converter issue??? Thoughts???
You have a 6-speed. There’s no torque in a 6-speed. It’s a clutch.
My 01 silverado isnt stock.My sister drove it ten miles. She decided to check my fluids.she determined it was low on tranny fluid. She then overfilled it.If you measured her gaffe id say the distance from tip of stick to full is approximately the distance overfilled.i gave it some gas. Enough to make it drop to low under a bridge at 3o mph to hear that sweet sound of the exhaust echo.However it wasnt smooth.unfarmiliar jerk before launch. I then let off and was coasying.all the sudden it felt as if id been rearended.i believe tbe rear tires even barked.since then tbe one block i drove it it wont go into 2nd.no shutters. No slipping. The more throttle ya give it its like the e-brake is being applied and it will come to a halt with a Gawd awful thud.i have to stop. Go to park then start again.as long as i leave it in low it can take any throttle.shift up or leave in drive its lijke a rubberband is tightening then it will stop itself fast followed up with the thud that shakes my ancestors in Africa..i removed excess fluid.appesred to be maybe 1/2 a quart.disconnected ground turned on lights fir an hour to no avail.as she only repeats the same . ive noticed a humming at high speed and rpms .sounding almost like a supercharger intermittently over the past week..mysuper tuner was set to stock plus 20 psi as well..so tell me guys..is she toast? Fluid doesn’t stink and is right color
94 Jeep Wrangler when I come to a stop it wants to keep going. If I leave my foot on the brake it will die but if I shift it to neutral it will stay running. Need help
08 ford Escape tourqe converter has somehow scrubbed against the bellhousing and create a lip on the torque converter where front seal will not come off of the torque converter does this mean I need a new torque converter
Just bought 98 dodge ram 1500 with 5.9L has 153,000 miles. Less then 20,000 on rebuilt transmission. They added larger pan. It sometimes seems like it shifts twice, sometimes have to press gas pedal more then should to get it to accelerate and I’m averaging 10.5 miles to gallon. Suppose to be 11 city 16 hwy and I do about 50/50. Is this a torque converter issue or something else?
Want go in any gear after I replaced the front seal the engine turned over then locked up so I took the transmission back down an put the torque converter on probably put up transmission now no movement in any gear
1991 f350 7.5 e40d transmission by the way I really need help
I have a 2007 ford crown Vic police interceptor and it will not change into 3rd gear
Torque converter clutch circuit electrical system 2003 mercury marauder code po743
Engine shuts down on breaking
2015 ram promaster 2500
No check engine or other indicator lights would appear.
Engine would not stall on very light breaking to stop.
Regular breaking would stall, sometimes launch truck slightly forward with RPMs fluctuating .
At this point by shifting into neutral engine would not stall.
Been apx-four weeks at the dealership service department now. They changed out the brake booster that didn’t work. Now they have an A-technician on this saying torque converter? The FCA is also involved”any answers for this would be appreciated..
04 trailblazer 4l60e. Had trans rebuilt about a month ago including(supposedly)new tc. Yesterday it started slipping and neutralizing. Turn off restart, it works for a minute then will neutralize again. Turn off restart same thing over and over. Does good when cold messes up when warm up
teaspoon of fluid leakin out of the dustshield daily
I have an 05 Ford F-150 with a 4R75W tranny. All of a sudden one day it simply would not go. I put it into drive and nothing happened when I stepped on the gas except the rpms would rev up. The codes I have right now are p0731, p0720, p0732, and p2106. Does anyone know how to diagnose these?
I just got a transmission rebuilt a few weeks later my engine light came on and i had a reading saying that my transmission was slipping i took it back to the shop were i had my trans rebuilt he straight told me it was my torque convertor so im thinking that should of been included in rebuilding my transmission in the first place im i correct.
Yes, i was thinking the same thing because it happened to me on my 05 acura tl
Replaced tranny in my 2003 avalanche it ran 2 days and then lost all gears at once
I have a 05 chevy tahoe. Its making a terrible grinding noise. When I put it in reverse with my foot still on brake its grinding so loud. When I put it in drive it doesnt make that noise until i take my foot off brake. I had transfer case replaced and the noise is still there. It seems to shift fine. But the noise is constant so I cant drive it. ANY IDEAS?
My 99 Dodge 1500, has a new problem. I start it in the morning and all is ok. As soon as I put it in “Drive”, I hear a clicking noise from the transmission. I thought it was the flex plate, but I looked closer and found no cracks or warps that would cause that kind of noise.