Grinding when changing from high to low range

I’ve got a 13 reman unit in mine with less than 500k on it, that has a few odd - intermittent ‘issues’.

My mechanic rebuilds them and said he’s seen poor workmanship and parts used in the reman units that he’s refurbished.

I’ll likely have him tear mine down and do it right.

 

Synchro is approaching to end of life...

 

Synchro in back unit is bad you can pull the back off without pulling the trans

 

Does it do it worse when starting out in the morning on cold days.. sometimes it's a air leak caused by these crappy push fittings newer trucks have which tend to leak more in the cold

 

Hi lo syncro.It will eventually cause serious problems if not fixed.I used to pull the back off my Road Ranger when it needed a hi low syncro in about an hour. Knock the driveshaft off, drain the oil out and get a good trans jack. Their are threaded jackholes on the rear section to seperate it,and get it sliding back off the dowels. On a cabover it's a piece of cake,just need a cherry picker.
When you get the unit out and on a bench,you need a press to get the bearings off and on,to replace the snycro. Not a tough job,but is a heavy unit to wrestle around when your doing this. Also gears have to be timed when you press it back together. When you reinstall there are mounting dowels,to help you line it up when you go back together with it.Must go in perfectly straight,to engage the bearings,be careful. Total time start to finish should be in the 6-8 hour range. At least I could do it in that time when I was younger.Good luck.