splitter synchronizer gone bad?

I have one that does this occasionally and a mechanic friend of mine told me to change the filter/regulator, it's one in the same. It's on the side of the tranny, you can do it yourself. Haven't done it yet but I had the range synchro go on a 13 speed and it would just grind every time you shifted it so I don't think it's the synchro

 

My 18-speed did it to me once in a while mostly when I splitted 5th gear. when it did it my whole truck would shake. A local gear guy told me to replace a spliter valve cover for an updated one with smaller orifice holes. Replaced it a week ago and it shifts really good. It is on a back of a tranny just below a driveline on a drivers side with one small airline and another bigger hose going to it. The price is around $90.

 

Could be a number of issues before you start dumping money into it i would have i checked out, could be something as simple as an air leak. I had the same issue with one of mine and it turned out to be bad syncros after i changed the filter regulater and some other small valves that can cause the same issue ,i just pissed the money away.

 

I didnt think the splitter had a syncro just the high low range. Correct me if Im wrong.

 

the splitter doesnt have a synchro. Only the high/low range have a synchro. If the synchro is bad it would grind. You might have some rust/junk inside the range cyl or the range cyl o-rings could be bad and bypassing air. Air pressure at the regulator filter i believe is 90 psi, you can plum an air gauge in an empty port to check. The insert valve is located on the splitter cover. You can download the manuals at roadranger.com and select literature and then select your trans model. eaton's are really easy to work on especially the rear section.

 

Hello I just bought a freightliner Columbia 2004 when I got this truck everytime I downshift into 5th gear loud banging noise came on mechanic said that’s you’re splitter synchronizer so I changed it 3 weeks later the noise came back not as often as before but I don’t know when it is anymore I spent a lot of money.
can anyone help me what can it be ?

 

Super 10?