4R100 hard shifting no more

[justinspencer71]

When it shifted hard going into second was there a knocking that went away right after it shifts?

 

[CaperCanadian]

If you mean the hard bang that happens when it shifts yes.

 

[justinspencer71]

No, it almost sounds like a lifter knocking while the RPMs are about 3500.

 

[CaperCanadian]

Ok i think i know the sound you mean now. Problem is last time i heard that was in my camaro before it tosted the trans. was the line pressure valve fluttering because the pump was gone. not sure it would be the same here. If you good with tools wouldnt hurt to drop the pan, good place to start problem solving. If nothing there go for the valve body and check the springs. May also have a look at the u-joints one might have some play in it.

 

[justinspencer71]

I changed the springs yesterday but that was not the problem, springs were all intact, the new ones were a little stiffer so I put them in. still have the hard shift from 1-2 a little softer 2-3 and smooth 3-4 same slowing down. Goes into 1 with no problem and same with reverse, no slippage takes off ok. with the other problems I am having I am thinking maybe the PCM...Overdrive kicks off and the light flashes, speedometer bounces all over the place or sits on zero (pretty random as to all three...working right, bounces or sits) Odometer randomly goes to dashes all the way across. I have had P0720 code twice I have changed the OSSS and the VSS and both times ran great for about 20 miles then acted up again but the service light didn't come back on for quite a few days.

 

[08montana]

Could this be the problem on a '08 Exped as well? I've had a hard shift 1-2 for the past 10k miles or so. Also I'm at 100K on the clock, I changed to tranny fluid at 60K. What do you guys recommend for how long to go between trans fluid changes?

 

[Ristin]

I originally found this thread while looking for something unrelated. lol, so glad I bookmarked it.
Decided to pull the valve body while doing a fluid & filter change.