Most torque converters multiply torque in a 2. Lean on the gas and stator speed falls behind and torque multiplication comes into play, which is when you feel gut acceleration. General Motors was first with a true torque converter in the 1949 Buick Dynaflow transmission. Since this part shares fluid with the transmission, if it were to become faulty, it could damage the entire transmission due to the debris caused by the part. Fluid Flow There are two basic types of flow: rotary circular and vortex roundy-round circular.
Choosing a Torque Converter Most manufacturers categorize torque converters by size and stall speed. On the third visit all four tires were replaced. With output speed sensor on top of extension housing. Highperformance engines normally make peak torque around 3,500 rpm, with peak horsepower rolling in around 6,000 to 6,500 rpm. The Germans were among the first to use torque converters in automobiles, trains, and industrial machinery. .
These converters are off-the-shelf dead-stock pieces that are not always designed and constructed for performance purposes. The torque converter is a fluid coupling for automatic transmissions that allows the engine to transfer power to the transmission. Records from National Highway Safety Transportation Administration show that Ford argued that it had a low complaint rate for this malfunction and only two accidents that resulted from a failing torque converter in its vehicles. You want a higher stall speed on a street engine when the application of power is expected to be in the 2,400- to 2,600-rpm range. I'm not a mechanic or an engineer, but it didn't make sense to me that the transmission could be making the noise if the rear wheels weren't turning.
Transmission parts supply houses generally sell stock torque converters with 1,500- to 1,900-rpm stall speeds. As the vehicle speed catches up with turbine speed, the impeller, stator, and turbine are all whirling around at the same speed. This costs you precious time on the quarter-mile or at the traffic light. Ford then followed suit in 1942 with a BorgWarner derivative in Lincoln and Mercury automobiles. Highperformance torque converters stall at higher engine speeds because you want the engine well into its power band when the converter stalls begins to move the turbine and vehicle. When accelerating, the torque converter transfers increased torque to the transmission.
Stall Speed The point at which the impeller begins to drive the turbine is known as stall speed. During acceleration, the stator turns at a slower speed than the impeller and turbine, which directs fluid flow more aggressively against the turbine blades. This makes normal driving difficult. But the loss of power can be dangerous for people driving behind these recalled vehicles. The second time the drive shaft was replaced. You want the torque converter to take hold stall at 2,400 to 2,600 rpm as the engine begins to make power. Worn, low, or absent fluid may cause the transmission to overheat.
On the fourth occasion another drive shaft and pinion gear was replaced. Signs of a faulty converter include transmission slippage, shuddering and delayed shifting. After, step on the gas as light as possible a few times, allow the car to idle for a few seconds and then hit the brakes, followed by shifting the gear into drive. Last Updated: August 9, 2018 The torque converter, in layman terms, is designed to transfer the power from the engine to the transmission. During hard acceleration, you can feel torque multiplication stator stationary or slower than turbine speed. On the first occasion the left front tire was replaced and all tires were balanced.
This can lead to transmission fluid leaks. Older torque converters have drain plugs for servicing, needed every 30,000 miles or 3 years. If you run a high-stall converter with a stock engine, slippage occurs until your engine reaches the high stall speed. This is known as a tight or loose converter. And this fact alone helps determine your quarter-mile times and the way your Ford behaves on the open road. This Tech Tip is From the Full Book,. If you closely examine the fluid and notice any grime, debris or sludge-like material, then this is a sign of contamination and the fluid should be changed immediately before you start driving again.
Any time you step on the gas, stator speed slows momentarily to help direct fluid and multiply torque. An investigation into this parts defect was launched in 2009 due to 65 owner complaints about the vehicle. This prevents stalling by allowing the engine to run while the transmission is stopped. As the diameter of a torque converter decreases, stall speed goes higher, which is why race converters are generally smaller than street converters. This is the noise that my 06 Ford Expedition 5. When the turbine gets underway with the vehicle in motion, the stator moves at the speed as the turbine. A trans shop wanted to rebuild it for 2200.
When in neutral, park, or slowing to a stop, the torque converter isolates the engine rotation from the transmission. So, even when a new part is installed, it can become contaminated, leading to failure in the future. How to test for a torque converter problem To see if the torque converter is, indeed, the problem, there is a simple test you can try at home to see if the part is likely the culprit. The vehicle still has the same problem after all of the repair attempts. If the torque converter fails, it causes loss of motive power and will bring the vehicle to an inevitable stop. As the vehicle gets up to speed, the stator slowly begins to rotate to crankshaft speed. Stock engines normally make peak torque around 2,000 to 3,000 rpm, with peak horsepower coming in around 5,500 rpm.