What does the accumulator piston do in a transmission?

The GM Genuine Original Equipment refurbished automatic transmission accumulator pistons are hydraulic dampers for the transmission hydraulic clutch circuits. The accumulator piston cushions the application of the clutch pack, which provides smooth gear changes.

How does a TH400 work?

The TH400 transmission takes advantage of an electrical slide switch controlled by the throttle linkage. On the other hand, the TH350 uses a mechanical cable kick-down that is connected to the throttle linkage. Despite the difference, the TH400 is considered the heavy-duty version of the Turbo-Hydramatic 350.

What effect would a broken accumulator spring have on a transmission shift feel?

A broken accum spring would cause 2-3 gear shift effects as well either harder or softer depending on throttle. Your AOD might have a stuck or leaky accumulator as well.

What does a 1/2 accumulator do?

The addition of this throttle-sensitive, 1-2 accumulator pressure helps to better control the shift feel based upon the speed of the vehicle. So, a higher speed will result in greater back pressure to the accumulator piston, which will result in a firmer and quicker 1-2 shift.

What causes a Turbo 350 to slip?

Slipping. If the transmission slips, meaning that it does not accelerate the vehicle smoothly, check the fluid level first. If the transmission has enough fluid, the vacuum modulator could be defective, the modulator’s valve may be sticking, or the oil strainer may be plugged or leaking.

What kind of conditions would be present if the accumulator was left out of a transmission?

Without a shift modifying device like an accumulator, the device applies suddenly, and harsh shifting occurs. An increase in throttle pressure increases the pressure on the piston’s bottom, assisting the spring and providing a firmer shift.

What does an accumulator spring do?

Accumulators are shift modifiers that affect transmission shift timing and quality. They absorb the initial shock of high pressure in the apply circuit. When a clutch or band’s piston or servo first strokes, there is little pressure in the circuit.