Shifting Concerns

I look at downshifting as its backwards compared to upshifting. Instead of letting the rpm to drop to get the gear to float in you have to raise the rpm and double clutch when you need to.

 

What type of truck and transmission?

My theory is that since 6 gear is much taller than 5th you need to wait longer to shift into 6 so you need to wait longer for the engine rpms to go down----because the wheels/transmission aren't turning fast enough in relation to the engine speed at that road speed.

7th is even wider away than 6th is to 5th.

8th is far away from 7th in terms of spacing

9th and esp 10th from 9th and so forth for a 10sp trans.

1234 tend to be closer together is gear spacing----not as big a difference between them vs. the higher gears 7,8,9 19

 

ten speed transmssion in a freightliner, it seems hard to get the timing right for each gear when downshifting

 

It should come out at 1100-1300 and go back in at 1600-1800 or something like that for downshifting.

i would have to double check as i don't use the tach anymore----i just go by feel.

 

Use your RPM's (tach) to downshift. When the tack gets to 1350, clutch-rev-clutch...the punch of the throttle should be a quick shot, to bring the rpm's up about 400-500 ... don't over depress the clutch peddle...a few inches past the resistance point is enough. Generally when you over depress the clutch peddle, you have lost your "rhythm"...don't do anything fast, a smooth steady speed is always the best.

Keep your tach about 1500-1650 in any gear, once your get to any point above that you are over taching and will have trouble getting out of the gear, also the rev up will have to push to about 1750-1800 to achieve the next gear down...way to high, especially for a Detroit (most common engine in a Freightliner)

 

I have a mercedes benz mbe4000

 

I think my problem is when I want to downshift I get it to come out of gear then I think i might be in nuetral to long...example 10 down to 9 bring rpms down to about 1100-1200 get it to nuetral, this is where i think I get screwed up is that I am in nuetral to long so then I start to apply fuel to try to get the rpms up sometimes goes smooth other times not.

 

i was taught once the rpms are 1000 or below is when you need to downshift, and so far it has worked. below 1000 clutch rev clutch. like stated dnt press the clutch in so much, and dnt be afraid to rev it up.

 

Most want to over rev on the downshift. Come out of gear under throttle, then a light tap will be closer than a big rev.

There's another BAD technique I seen another driver use which is actually slick watching. He pops it out of gear and holds a steady throttle. Then left foot braking he uses road speed to match the going in the next gear instead of engine speed.

 

I respectfully disagree. To have control of a vehicle the operator must be capable of any and all functions of their equipment.