Noob having a problem down shifting


Steve C

Steve C

Member
I realize that with a grand total of 13 miles under my belt I'm going to have a ton problems but . . .
I've probably driven a million miles in my life, including quite a few miles on old dump trucks with bad transmissions, and I can't believe the problems I had yesterday.
I'm in school and am learning on a Super 10. For the life of me, I couldn't seem to spin up the RPM's fast enough / high enough to downshift. I'm sure my instructor knows what he's doing, and he's a great guy, but he is not starting us off double-clutching (just single), even though I've heard the DOT test requires this.
I'm driving again on Monday. Should I try to double clutch or will this just foul me up even more?
Thanks for any suggestions.
 

First, don't clutch all the way to the floor. That is a very typical noob mistake. I did it myself. Second, hit that throttle hard. The worst that will happen is the rpm will go higher than needed and you will have two opportunities to put it in gear.

I hate super-10's, too.
 
Injun said:
First, don't clutch all the way to the floor. That is a very typical noob mistake. I did it myself. Second, hit that throttle hard. The worst that will happen is the rpm will go higher than needed and you will have two opportunities to put it in gear.

I hate super-10's, too.
Click to expand...

Yeah, the clutch all the way to the floor was one of the big issues until my instructor finally mentioned it.
Also, I already hate the Super 10 - I can't even guess how many times I forgot about the button and just shifted.
 
Injun said:
First, don't clutch all the way to the floor. That is a very typical noob mistake. I did it myself. Second, hit that throttle hard. The worst that will happen is the rpm will go higher than needed and you will have two opportunities to put it in gear.

I hate super-10's, too.
Click to expand...

Steve C said:
Yeah, the clutch all the way to the floor was one of the big issues until my instructor finally mentioned it.
Also, I already hate the Super 10 - I can't even guess how many times I forgot about the button and just shifted.
Click to expand...

Please explain for those who may not know, why you don't want to push the clutch pedal all the way to the floor when shifting.

(By the way, I already know why, and yes, when I was a n00b I did it too!)
 
If you push the clutch to the floor, you engage the clutch brake, which stops the motion of the gear that's supposed to mesh with the transmission. At a stop, this is useful because the transmission gears are not turning. When the vehicle is in motion, however, the transmission gears are turning. When the clutch brake is engaged, the drive gear (fly wheel? :dunno:) stops and you find yourself trying to shove a stationary gear into a moving gear. Truck gears are squared off and not synchronized and are far less forgiving than cars with their tapered, synchronized gears.

Somebody with a little more tech-knowledge than I have will need to explain the process of synchronized gearing. It's beyond my pay grade.
 
Heck today I had a heavy load. I am pulling up to a T Road and was downshifting. Came out of gear and forgot what gear I was in. I never think about the shift I just shift. I float most of the time. I don't know what the heck I was thinking. The gear I tried to hit was way off so I just took a second to get my composure and grabbed a gear.
 
Injun said:
If you push the clutch to the floor, you engage the clutch brake, which stops the motion of the gear that's supposed to mesh with the transmission. At a stop, this is useful because the transmission gears are not turning. When the vehicle is in motion, however, the transmission gears are turning. When the clutch brake is engaged, the drive gear (fly wheel? :dunno:) stops and you find yourself trying to shove a stationary gear into a moving gear. Truck gears are squared off and not synchronized and are far less forgiving than cars with their tapered, synchronized gears.

Somebody with a little more tech-knowledge than I have will need to explain the process of synchronized gearing. It's beyond my pay grade.
Click to expand...
The drive gear is on the input shaft inside the trans. The drive gear turns two other gears on two shafts in the trans, this is what as known as the twins shaft transmission and on these shafts are the drive gears.

Then you have what is called the "driven" gears that are in the center of the trans that you shift with the shifter and they are hooked up to the output shaft.

View attachment 19190

The slick looking round thing "used" to be a drive gear. On the right and left side of the slick gear are also drive gears. The gears in the center and inline with the slick gear are the driven gears that you move with the shifter.
View attachment 19190
 
Tim, those two gears look like they got BLUE hot....what was the deal with that trans?

As far as the OP...this is something that comes with time and practice.
If you think about what you're doing, you mess up.

I had a heck of a time with downshifting - but one day, it just clicked.

Kinda like floating gears. :banana:
 
Hanadarko said:
Tim, those two gears look like they got BLUE hot....what was the deal with that trans?

As far as the OP...this is something that comes with time and practice.
If you think about what you're doing, you mess up.

I had a heck of a time with downshifting - but one day, it just clicked.

Kinda like floating gears. :banana:
Click to expand...

I really dont know what happen with that trans.....its a pic I found on the web while looking for a open top trans to show what are drive gears and what are driven gears.
I'm guessing beings thats the input shaft gear it was damaged by either a tooth coming off and over time it finally took the rest off.
Now what took the tooth off is another guess in its self. Input shafts can be damaged any number of ways, the most common is backing into a dock to hard without disengaging the clutch in time. Another way is a high horse power motor and the lack of knowing when to down shift into the right gear when climbing hills, I dont think that happen in this case because the gears are to clean and free of burnt oil, or they cleaned the hell out of it before taking the pic.
Another thing that "could" cause that is the harmonic balancer is wore out and the harmonics of the engine is going through the trans causing gear chatter.
 
Injun said:
If you push the clutch to the floor, you engage the clutch brake, which stops the motion of the gear that's supposed to mesh with the transmission. At a stop, this is useful because the transmission gears are not turning. When the vehicle is in motion, however, the transmission gears are turning. When the clutch brake is engaged, the drive gear (fly wheel? :dunno:) stops and you find yourself trying to shove a stationary gear into a moving gear. Truck gears are squared off and not synchronized and are far less forgiving than cars with their tapered, synchronized gears.

Somebody with a little more tech-knowledge than I have will need to explain the process of synchronized gearing. It's beyond my pay grade.
Click to expand...

Pretty good explanation Injun. Thank you.

Also, engaging the clutch brake while the truck is moving will cause premature wear to it, so a driver must avoid the habit of depressing the pedal all the way down during shifting while moving, like is usually done with syncromesh transmissions.
 
Tim said:
The drive gear is on the input shaft inside the trans. The drive gear turns two other gears on two shafts in the trans, this is what as known as the twins shaft transmission and on these shafts are the drive gears.

Then you have what is called the "driven" gears that are in the center of the trans that you shift with the shifter and they are hooked up to the output shaft.

View attachment 19191

The slick looking round thing "used" to be a drive gear. On the right and left side of the slick gear are also drive gears. The gears in the center and inline with the slick gear are the driven gears that you move with the shifter.
Click to expand...

I find it interesting how even having 2 shafts of gearing to handle the torque does not prevent this kind of damage. But then, after working on rigs at the power company for 30 years and seeing what linemen can do to a truck, it doesn't surprise me.
View attachment 19191
 
Don't feel bad. Took me a few months of real driving before I could downshift. It's a feeling that you will acquire.
 
It comes with time, just takes a little longer to figure out the downshifting as opposed to upshifting.

Super 10's can be a little weird, but at least the bulk of the downshifting takes place with just the flip of a button (when you just gotta drop out of the top gear)
 
Shifting comes with time. I taught myself how to float, downshift, and some other bad habits. It was ugly at first.

Downshifting for me is done with a quick glance at my speed, muscle memory, and the sound of my engine. I knew where my truck 'liked' to take gears so that helped as well. Every truck and tranny is different in their own ways. I always said, "The truck is like a woman, she will take it when she is ready, don't rush her".


Sounds complicated as a new driver but someday you will remember this post and understand it.
 

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