Ideas for Low Pressure in Transmission Shifting

This is related to my old post where I've been feeling a shudder at low speeds and low RPM's. Just had the fluid flushed and still feel it. Took it to a real transmission guy and he says trani is really solid, torque converter is good but there's just some low pressure in the shift from 3rd to 4th sometimes causing the chatter. He was gonna do some digging to see what the solutions might be and get back to me, but while I wait, I wanted to get your take.

Have you guys ever experienced this low pressure in between shifts and how did you fix it?

Thanks

 

I don't remember the old thread, but you did confirm this wasn't rear-end shudder, right? The LSD in these trucks is notoriously finicky about what fluid it takes and will shudder like crazy at low speed, especially while backing out turning, turning from a stop, if you fail to heed it.

Are you throwing any codes? And do you know what fluid was used (WS, we hope), and confirm the fluid level on the sealed trans is properly topped off?

 

Yup, ATF-WS; no codes at all. My truck was experiencing the shudder before the LSD install and when installed, I used what the manufacturer required.

 

Right now, I'm agreeing with this guy's diagnosis. It makes sense to me.

 

The transmission guy let me know that one of the clutches is out. That was his take