Mack T2130

Not sure about the 18 speed part but my uncle worked as a mechanic for tri-valley waste, which was bought out by waste management, then worked for waste for 25 years. He said he's never found a broken tooth on a Mack trans out of the thousands he's had open.

After seeing what kind of abuse the T310M's take at my part time construction job, I believe Mack makes the toughest trans on the market

 

I had a 97 E7-454 with a 2130. No complaints, quiet and smooth, although not quite as quick shifting as an RTLO. IIRC, you also do not preselect the splitter on the Macks.

Here's a post about 13 to 18: Mack 13 Speed to 18 Speed Conversion

 

We dug into that on a thread on here once upon a time. If you go through the power paths, there's a spot in low range/ high split where there's a really high speed differential that never happens in a 13 speed. And in the 18 speeds there's a bearing there instead of the bushing that's in the 13. One of those deals where you probably never hurt anything unless you were using that under a high load.

I've driven the old 13 speeds before they had interlocks on them, so you could shift the bottom side if you wanted. But most stuff was so short geared back then that there wasn't much point!

 

I think the typical Eaton scales in at around 750-800 lbs.