Peterbilt Eaton 18 speed transmission

[kjames]

I have a 2020 Peterbilt 389 with 18 speed transmission. When shifting from direct to overdrive the transmission shifts in hard when I let off the accelerator. Peterbilt said o rings leaking oil and replaced them. Still doing the same thing.

 

[mndriver]

My 13 was giving me that issue.

I replaced the range selector.


Did it based off the troubleshooting manual.


Here’s that manual for the 18 spd…

https://www.eaton.com/content/dam/eaton/products/transmissions/vehicle-transmissions/troubleshooting-guides/eaton-fuller-transmissions-troubleshooting-guide-trts-0070-en-us.pdf

Where I found that. And the parts manual is there too.

RT-18 manual transmission

The Eaton Fuller RT-18 manual transmission is the iconic industry standard for heavy haul semi truck transmissions with ratio flexibility and unlimited GCW.

www.eaton.com

 

[kjames]

Thank you very much. Peterbilt should know that but so far haven’t fixed it. Still under warranty.

 

[mndriver]

It’s not a part of their laptop diagnostics process to think…

 

[mndriver]

If you haven’t, I’d highly recommend servicing your air dryer too.

 

[kjames]

Thanks. I’ll do that.