7k mile trans problem

[Blazin8556]

I rebuilt my e4od this past summer. It's got new clutches, steels, shift kit, sun shell, forward planet(I think), seals, bushings, torque converter (supposed to be triple disc), and a reman solenoid pack.

First built it, it was fine and dandy. I run back roads to work to keep rpms down. Good clean firm shifts. One day it was like the shift kit was taken out and it shifted smooth as glass and I could hear the rpms change with gears but no firm bump. Ran it down the interstate later that day. I got the firm bump back.

Today I got halfway to work and it went back to glass shifting. On the way home. Interstate at 75 mph. Getting onto my road still shifting smooth. I had been noticing a little bit of shudder when od or lockup happens, not sure which cause it kinda acts like it will flip od and lockup depending on how I drive it.

What happened to my firm shifts?

I might add there are 4 large pieces of fire wood in the back to add weight due to recent freezing storms trying to increase traction if it started spinning. I had good shifts all week now this.

[Blazin8556]

This is my shift kit. Shift Kit E40D 4R100 Transmission Shift Kit Transgo Shift kit

[Blazin8556]

Seems to have worked itself out. Gonna do a fluid and filter change tomorrow. Got some synthetic trans fluid to go back in. Would it hurt anything if there is still the old fluid in the trans when I put on the synthetic?