Anyone know 13 speeds Eatons really well?

That's good. Just make sure to check exhaust out of shifter and spliter valve. Air might get in, but it has to come out too. Then I would follow @Goodysnap advise.

 

Funny you mention the exhaust ports plugging. We had some new trucks waiting to be delivered to the customer. They sat on the new truck line during the Covid shutdown for 6 months before they finally took delivery. 18 speed autos. 1 truck kept intermittently throwing splitter failed to engage. Mud dabbers or some bug had nested in and plugged the exhaust port while it was setting? Truck had 2500 miles on it. Who pays for that one?

 

I have had those sheets travel the length of a trailer and nest at the brake valve. What a nightmare to have frozen brake symptoms in the summer. My trailers get glad hands covered when not in use.