Eaton 18 speed rattle noise

Without driving it in person, I think what your hearing or feeling may be somewhat normal. Have you driven another with the same age and milleage to compare?

Lower gears will tend to make a growl/chatter type vibration with some age.

With no metal on the plugs and it holds all gears fine, I say run er. If it gets worse it's likely reman time anyhow.

 

A shot in the dark.
Maybe it's the shifter itself, or shifter related, forks, sliders, just worn out?

 

Pilot bearing doesn’t spin when clutch is engaged and throw out bearing noise wont change with load or unload it’s either tranny or diff related transferring up drive shaft like pinion hitting carrier.

 

Check A box countershaft play might just need to re shim it

 

It's your countershafts in the transmission. They will rattle at low rpm in gear coasting. Completely normal. Just depends on mileage and wear how bad it might be. Sounds like yours is getting tired. My suggestion is keep your rpm above a 1000 when crawling in traffic.


Nothing to see here

 

It sucks when your transmission does it's impression of a rock crusher 500 miles from home, mine just did a couple weeks ago.

 

RTLO18918B will swap in no problems just make sure you get as similar a trans as possible eg bellhousing and yoke. The pto shouldn’t be a problem just need dial indicator to setup properly

 

release bearing is worn out. you said the noise stops when you press the clutch, thats because the linkage forks push on the release bearing to disengage the clutch. if you have no loss in power, or anything else and just a rattling noise which you obviously cant hear over a diesel engine running at 1200 rpm, but can at idle. i think your on the right track assuming the input shaft, but probably not as bad as it sounds.