10 Speed Transmission Question

So I've been testing this out on my ride home today. I've tried it going in both directions. I haven't noticed any grinding or anything abnormal doing this. Not saying i would recommend it. Also that doesn't mean that it's isn't messing something up internally, but shifting wise everything is still smooth. The only grinding I've had at all has been my fault and not being at the right road speed for the gear I was going to.

Range selecting in neutral should be avoided if the truck is moving as it can damage the transmission. If you are sitting still it's ok.

I do everything I can to preselect! If I am in low range I will try to slow enough to get it in a low gear.

on a ten speed, you can get it in 6th pretty easy if you're in high range, then preselect low before downshift ing.

there are times though that I screw up and change range in neutral while moving. I just hope I dont kill the transmission, and vow never to do it again.

In classroom we are told to NEVER switch from low to high, or high to low range with tranny in neutral..... so my question is how do you recover from a missed gear if your say in 6th going to 7th......mess up, and in neutral, but road speed is dropped to low for 6th and you need to get into 5th gear?

On simulator its not an issue, but sounds like real world it can cause serious damage.......

-Brian

I learned why your instructors were telling you this. I was driving a 10-speed Eaton-Fuller the other day and it's because it just won't work. Somehow I got myself into this situation and the only way for me to reset my gears was to come to a complete stop, put the stick back into 6th from neutral, stuck between 6th and 7th, stay stopped, flip the switch back down, shift into 5th while staying stationary and then shift down low enough to start moving again, which in this case, was 4th.

Yep, I was taking a road test and I had to casually coast to the traffic light in neutral and pretend like nothing was wrong and reset at the light while we were casually talking. If the tester noticed, he certainly didn't reveal it. I just acted like nothing was wrong and "felt" my way back to the right gears.

Yikes!

-mountain girl

In classroom we are told to NEVER switch from low to high, or high to low range with tranny in neutral..... so my question is how do you recover from a missed gear if your say in 6th going to 7th......mess up, and in neutral, but road speed is dropped to low for 6th and you need to get into 5th gear?

On simulator its not an issue, but sounds like real world it can cause serious damage.......

-Brian

I learned why your instructors were telling you this. I was driving a 10-speed Eaton-Fuller the other day and it's because it just won't work. Somehow I got myself into this situation and the only way for me to reset my gears was to come to a complete stop, put the stick back into 6th from neutral, stuck between 6th and 7th, stay stopped, flip the switch back down, shift into 5th while staying stationary and then shift down low enough to start moving again, which in this case, was 4th.

Yep, I was taking a road test and I had to casually coast to the traffic light in neutral and pretend like nothing was wrong and reset at the light while we were casually talking. If the tester noticed, he certainly didn't reveal it. I just acted like nothing was wrong and "felt" my way back to the right gears.

Yikes!

-mountain girl

It's amazing how much can be conquered by simply staying cool. Nice save, MG

How the selector was explained to me is that you must pre-select while in a gear because the range selector will operate when shifted to neutral from the source gear. So, if going to 6th from from 5th, you select the high range while in 5th - when you then clutch to neutral, the mechanism works, flipping the range.

You can see how things could happen if you us the selector in neutral...

It's amazing how much can be conquered by simply staying cool. Nice save, MG

-AJ D.

I know, right? Sometimes I do have good luck. The tester was very cool, and we were just blabbin' away, so I just didn't point out that my gears were all messed up. Yeah, la-la-laaaaa. "Just be cool. Don't say anything. Shut-up, shut-up," I said to myself.

-mountain girl

Ok we have another myth forming a life of its own here.

Range selecting in neutral should be avoided if the truck is moving as it can damage the transmission. If you are sitting still it's ok.

Not true. Here's a quote from a heavy duty truck transmission repair manual:

Pre-selecting: Range shifts can be made only when the gearshift lever is in, or passing through, neutral. The driver can pre-select a range shift while in gear

In other words, it's not going to make any changes to the range selection unless you're in neutral or passing through neutral but you can pre-select the range shift while you're in gear. It will not damage anything by making the range shift while in neutral.

Haven't you guys noticed that you can flip that range selector switch 1000 times while you're in gear and it doesn't do anything? That's because it will only shift from low to high range in the transmission itself while you're in neutral. So if you're in 5th on a 10 speed and you switch the range selector to high, nothing happens until you take it out of 5th and into neutral. At that point the transmission will switch from low to high range and you can go ahead and put it in 6th.

So you can switch the range selector while you're in neutral. You just have to give it a second or two to actually make the change in the transmission before putting it into gear.

Somehow I got myself into this situation and the only way for me to reset my gears was to come to a complete stop, put the stick back into 6th from neutral, stuck between 6th and 7th, stay stopped, flip the switch back down, shift into 5th while staying stationary and then shift down low enough to start moving again, which in this case, was 4th.

Honestly that was just a matter of inexperience. A lot of things could have happened that prevented you from getting back into gear. You might have lost track of whether you were in low or high range, you may have switched between the two and tried putting it in gear without giving it time to make the change in the transmission, you might have pushed the clutch too far and started hitting the clutch brake which slowed the transmission speed too far - could have been 100 things. But it would have gone into gear just like any other time if you would have matched up the engine speed, transmission speed, and road speed properly. But you did the right thing. You got it stopped, reset everything, and continued on. Great job :-)

Now we always talk about big rig transmissions not having synchronizers, but in fact they do in one area - the high/low range. Nobody has mentioned it yet but haven't you guys wondered what that whining or "winding up" sound is you hear sometimes when you shift from high range to low range? That's the sound of the transmission shaft speeding up to engage low range. Now you may not be able to hear it with all transmissions, but try this....downshift from the lowest gear in high range to the highest gear in low range - like 6th to 5th in a 10 speed. Listen closely to see if you can hear a whining or "winding up" sound in between gears when the gear lever is in neutral. That's the sound of the synchronizer speeding up the shaft to engage low range. That's why you have to give it a second after hitting the splitter, especially going from high to low range.

If your head is spinning from all that - here's the takeaway.....you can hit the splitter while you're in neutral. Just make sure you give the transmission a second to make the change before putting it into gear. Hitting the splitter only tells the transmission you want to shift from low to high range (or vice versa). The transmission has to synchronize internal speeds and meet other criteria before the actual change will take place. That's why you have to wait a moment before putting it into gear.

Good to know. I know I read in a transmission manual not to range select in neutral if the truck was moving. If I get time I'll find it and quote it. But, it makes sense that the reason why is if you try to put it in gear before its ready then damage could occur.

I know that one truck I had sometimes going from 6th to 5th it would act like it was in neutral until I hit the accelerator... usually when coming in to a rest area and downshifting before getting to my space. It only happened in that one truck. Several times "strange" things happened, but usually taking it out of gear and putting it back in fixed whatever it was.

Ok, I found the stuff I had read...

PT 1:

IMPORTANT: Always preselect all range shifts when upshifting or downshifting. Preselection requires that the range lever is moved to the needed position before starting the shift. Preselected range shifts are completed automatically as the lever is moved through neutral and into the next g ear. Preselecting all range shifts prevents damage to the transmission and provides for smoother shifts

PT 2:

Never move the range lever with the shift lever in neutral while the vehicle is moving.

So, at least you know where I got the information!

Eaton 10-SPD Manual

Ok, I found the stuff I had read...

PT 1:

IMPORTANT: Always preselect all range shifts when upshifting or downshifting. Preselection requires that the range lever is moved to the needed position before starting the shift. Preselected range shifts are completed automatically as the lever is moved through neutral and into the next g ear. Preselecting all range shifts prevents damage to the transmission and provides for smoother shifts

PT 2:

Never move the range lever with the shift lever in neutral while the vehicle is moving.

So, at least you know where I got the information!

Eaton 10-SPD Manual

I had also downloaded this manual and it states in at least 5 different pages that you MUST pre select range finder before shifting gears and to NEVER switch range selector while in neutral with vehicle moving! ...... or you could do what I did today....instructor called it "ghost gear" went from 5th to 6th....flipped selector too late.....got into the gate for 6th, but nothing there....was in neutral....had to bring it back to 5th and flip range finder again....then it worked.... and of course I was panicking by that time.....and was too high on rpms....pushing in clutch too far engaging clutch brake.....yikes!

Considering how many times I've flipped the range selector in neutral rolling down the road, and haven't broke a transmission yet, I have to believe that it's ok as long as you let it complete the transition before putting it in gear.

Good thing I found this discussion... it's a LOT of stress I won't have to deal with now.

Thanks, Brett!