Thank you, sir...now back to our regularly scheduled thread.

 

So I have been reading this thread and I am about to attempt to fix the 1-2 shift problem.

I have previously dropped the pan, removed the accumulator body and found the Line pressure modulator valve per the Sonnex diagram and found a local Sonnex dealer for the part.

Link to doc: http://www.sonnax.com/system/announcement/96948-05K.pdf



Two questions:

1. How do you remove the actual valve? I was able to remove the retainer clip, but the valve did not come out and I did not want to force anything.

2. Mark Kovalsky sez "Make sure all are free and no springs are broken." How free should they be? I tried pressing them with my fingers. Some moved about 2mm and some did not move at all (without removing their clips).

Concentrating on the one in the diagram, it seems to move freely within the shaft when I remove the clip, but it does not come out.

Thanks for the help with this.

Homie

 

mine shifted the same with 7.3 4r100 until I turned off the programmer tranny mode.

 

After removing the clip you need to remove the plug. There is a threaded hole in the end of the plug. Screw a bolt in there so you can pull the plug out.

You are trying to move the plugs, not the valves. With a small pick you can reach in the passages to move the valve. Pushing on the plug doesn't mean anything.

 

Thanks Mark...

I see the threaded hole on the right cylinder in the diagram. I will try removing that one.

But what about the one on the left? It looks like the sonnex part is the one on the left in the diagram. I removed the "M" retainer clip, but the rest of the valve, etc., does not come out.

I'll probably run and get the parts today and tomorrow and start the work tomorrow.

Thanks for your help. cheers

 

Any idea what the size of the accumulator line pressure value is for my application? I think it is .427, but Sonnax has four sizes listed. I imagine it is either the .427 or the .500. I want to do a direct swap... no boring.

Thanks again.

-H S

 

Hi Mark. I am hoping your still around on this thread…. But I have a 2015 6.7 f250 it’s deleted. But under minimal acceleration I have a very hard shift into second. No other gear is effected but like others when I get into it it shifts perfect. But like I’m traffic and I hit the peddle a little and let off man it slams hard. Think it’s the same thing?

 

I don't know the trans in your truck. But I'll bet it doesn't have an accumulator, so it can't be the same problem.

 

Assuming a 6R140, here's what the FSM's "Diagnosis by Symptom" chart says:

You're going to need to use an appropriate scan tool (or comparable) to diagnose.