To avoid damaging Sonnax “D” clutch hub drum section during snap ring removal, always use drum protector tools such as Adapt-A-Case part no. T-3500AC or Automatic Choice part no. 8HP45.TOOL01.
The ZF8HP70 transmission uses “D” clutch hubs made from weak, cast A383 aluminum. Over time, the steel core of the clutch plates wear through the splines on the hub, causing failure. Wear can appear after just a few thousand miles, often resulting in burnt clutches. Additionally, the backing plate tends to flex, causing uneven wear on the clutch friction material. These issues lead to a high failure rate, sometimes even within the OE warranty period, and can cause loss of 4th through 8th Gears and Reverse.
Sonnax "D" clutch hub 35570-70K is a riveted two piece assembly that provides a steel hub that prevents wear from the steel core of the clutch plates. This new hub also is fitted with a new bushing and is ready to install.