You are buying a tool that is used to expand the sealing rings on either a 700R4, 4L60 or 4L60E transmission.

We invented this little tool, we call it the “mushroom”.  If you see another listing with a similar part, it’s an off shore copy!

This works on ALL the 4L60(E) input shaft, both the 298mm version and the 300mm versions.

It is very simple to use:

  • Lubricate the expander
  • Simply slide the desired seal over the tool
  • DO NOT leave the seal(s) on the tool for any great length of time, doing so will cause them to over expand.
  • Remove the seal from the tool
  • Center the new seals in the groove
  • Lubricate the seal sizer with trans-gel
  • Gently guide the appropriate sizing tool over the seal to collapse it into the groove and properly size it.

We also have the seal sizers available and will combine shipping on multiple orders.