Please need help (downshifting)

Hi I am training on a 2003 frightliner and was wondering what should my speed be when downshifting gears

 

What trans? 9 speed? 10 speed? 13 speed? Auto matic or manual? What are the rear axle ratios?

 

10 speed I need to know what speed I should be downshifting at and which gears my speed should be at

 

Not speed. Rpm, let it drop 300 slide it in, or bump it up 300 rpm

 

I’ve tried downshifting from gear 8 to 2 but my
Instructed keeps saying watch your speed

 

What kind of school are you going to that uses an 18 year old truck?

 

Speed is irrelevant

 

So if I’m in gear 7 going 30km and want to shift to 5th the speed won’t matter ?

 

After you get use to things. Notice how fast you can go in each gear.
I bet 2 is only good for 10 mph or less, 8 maybe 35 to 50 mph.
So if you’re trying to go from 35 mph into a gear only designed to go 10 mph, it isn’t going to work.

 

Like when I go into gear 5 I’d be at 20 km and it grinds