I didn't find where you are discussing heavy duty trucks, so I'll ask here about my Kenworth w900L, y2006( Suspension AG460, Transmission 18 SPD, Wheel Base 262). So, as you see I've bought it something like 8-9 years ago and everything was perfect excepts transmission, and I thought it's because I got it from unknown car delearship wallwork trucks, but I read some comments and as I know so far just I have such problems, unfortunately. So maybe someone can suggest me, which new transmission to implement? Because I think to buy from some different truck 13SPd. Generally, I haven't decied yet.

 

Maybe I need to throw a massive truck and start ride a ford f-150, for example?