shrike

iTrader: (1)

Hi,
I have my valve body out in my 1999 4L60E transmission that comes from a 2wd truck.

I am trying to find som info on the springs and the different colours they have in the forward accumulator, 1-2 accumulator and 3-4 accumulator.
I would like to replace the plastic pistons on the forward and 1-2 accumulator and probably the 3-4 accumulator piston since I understand it is easy once the VB is out.
But I am not sure if I can use the springs that are with the plastic pistons or should I replace them? If so what colours?

I don't mind having a bit firmer shifts but since I don't dig deeper in the trans and I don't replace anything else besides the separator plate and the PWM valve with one that acts as on/off I am not sure it is worth it.

I tried to search the info for a couple of days wihout success

mrvedit

The highly preferred aluminum pistons for the 1-2 and 3-4 accumulators use the same springs as the plastic pistons. I don't know what colors give you firmer shifts as I use either the Transgo HD2 or Sonnax Performance Pack springs.
I don't think there is an aluminum piston available for the forward accumulator, but Sonnax makes a pinless one. You might consider Pinless pistons for both the 1-2 and 3-4 accumulator; you can use the same springs with them.
(The HD2 1-2 accumulator springs do NOT work with Pinless pistons.)

Correction - Aluminum forward accumulator pistons are available. See below.

shrike

iTrader: (1)

thank you for your precise answers!
I will be able to order my parts today

72blownvert

There is a aluminum forward accumulator piston available. Anyone selling these parts should have them.

mrvedit

Thank you for the correction.

shrike

iTrader: (1)

I went ahead and ordered all pinless pistons. The reason is that I was getting confused anyways with all the descriptions. And I wasn't sure anyways if they had the seals which seemed to be sold only as part of a rebuild kit. At least like this I know I am getting everything.
I will also be replacing the solenoid seals since I am in there.

mrvedit

Good choice. The same Pinless piston kits fits both the 1-2 and 3-4 accumulators. This is much less confusing than figuring out which piston pin diameters your trans is using. Also the Pinless pistons use two seals (instead of just one) and therefore seal better in worn bores.