Why do I scratch my gears when I upshift.

I don't think anyone has mentioned that you need to control the accelerator pedal also. If you drop rpms too fast by lifting your foot to fast then your window where things mesh is gonna be just a few brief seconds. That is, your shift will need to be perfectly timed to not grind gears. Learn to feather your accelerator up and down a couple hundred rpm when things don't mesh right and you may find it dropping into gear easier.

 

If you are trying to shift too quickly, or too slowly after disengaging the prior gear, the engine RPMs might not be right for the gear you are shifting into.

When I first learned to float, I ground gears horribly because I was trying to switch too fast.

 

I don't think we're talking about the same thing.

When you are floating gears, when you upshift, you can change gears too quickly.

Reach 1500 RPM.
Pull stick against resistance.
Release accelerator.
Shift to next higher gear without clutching.

That's the super-simple explanation, but if that is all you do, you will scratch.

The act of shifting to the next higher gear needs to be timed.

AFTER disengaging from the lower gear, you have to wait for the engine to more closely match the appropriate RPM for the new gear at your current road speed.

In my current truck, if I am on flat ground, and float up a gear, I move the shifter pretty slowly, taking maybe a half second. If you just slam that shifter into the next gear as soon as it will let you, you will scratch. A lot. Most drivers learn not to slam gears like that, but if you still scratch after slowing down a bit, you might need to slow a tad more.

If I am on a upslope, the truck is slowing while I am waiting for engine RPMs to come down, so it needs just a little more time to match RPMs. On a downslope, you can shift a little faster. The differences are small though. I scratch now and then when floating on slopes, even when try to shift a little faster or slower, though I rarely scratch on flat ground.

 

someone has an itchy gear box

 

You can't force it.

When the rpms are right it will pretty much fall into gear. A light touch with a quick movement when it starts to fall in if that makes any sense.

 

Coming off clutch to fast . try floating

 

I wouldnt listen to that guy. The fact that you even care to learn how to shift smoother means your better than 90% of the drivers out there, in my book at least. And especially at such a young age. Some people are naturals to shifting, others (like me) have to put in effort to actually learn it. I was absolutely horrible my first year driving. I would never even down shift when coming to a stop because I couldnt handle it. Threw it from 10th to neutral and just coasted to a stop, lmao. Eventually once the other parts of trucking became second nature, I could focus more on my shifting. Still took some time, but now it is nothing. It becomes second nature, you dont even pay attention to shifting ... your mind and muscles just automatically shift whenever it feels/sounds right.

Only thing I can say, is dont be super afraid of grinding it. Grinding will teach you what not to do. Try shifting at even higher RPMs so it will give you more time to get into the next gear. After you take it out of a gear just hold it softly against the next gear. You should be able to actually feel when its ready to go in.