Tips on Shifting 10 Speed

To give you some help it'll be 400 rpms between gears. Watch your tach when you shift and sooner or later you'll get the hang of it

 

10 speed with c15 10 to 9th downshift about 55. Each gear good about 10mph. I shift 6th and up about 1400 to 1700 is that to high for this motor ? International 9200i 6x4

 

What you have is an 8-sp, not a 10-sp. The difference being that L is so low that it is generally too low to be used in 'regular highway driving'; so low that it would really only be used for low-speed laden climbing of steep hills, usually off-road. Also, the main difference between this and a 9-sp is that the first off-the-main-H gear marked "1" (where your "L" is..) is only used in the low range of the splitter, whereas it IS used on the upper-range on a 10-sp.

So, getting back to your original question, you only use "L" to get in and out of off-road locations with hills, and maybe for starting on-road when you have a VERY heavy (i.e., illegal...) load, then NEVER again afterwards.

BTW, back in my day, most of the heavy-haul 8-sp setups for dumps, etc used a "box pattern", where 1 was up and left, 2 was down and left, 3 was DOWN and RIGHT, and 4 was UP and right. The 'second stick' on a Spicer 6x4 I once drove was like this....

 

Open the hood and take a look at the data plate on your engine. It will tell you what RPMs your torque and HP peaks are at. As soon as you finish an upshift your RPMs should be just above peak torque.