Shiftin' Question

I hate to tell you, but if you are driving an American class 8 truck with a manual transmission, there are not any synchros! That is why you need to double clutch, or float the gears.

 

Ding Ding Ding

 

this is why i think double clutching is SOO stupid. To float on an upshift I let of the gas at the same time i've pulling outta gear into neutral, pause in neutral for a sec then slide right into the next gear. When you double clutch you are doing the exact same thing, if you wait to long or loose to much speed its still not gonna go into gear by clutching without messing with the fuel peddel.Down shifting is the same deal, left of the gas while pulling into neutral, give it the right amount of gas and slide it into gear(after years of practice you can do this without thinking about rpms or speed) again when double clutching you still have to match up your rpms to get it in gear. I'm my opinion(which i know is as good as shi t with all the ppl here) double clutching can shock load the drivetrain, wear out the clutch and linkage) Oh thats why so many companys prefer super 10's over straight 10's less double clutching by ppl that think you need to.But what ever works i guess, if you like double clutching go right ahead. Neither one is right i guess.

 

this what i need to learn....the double clutching,i failed schneider because of it i didn't.know how having a hard time finding a job..need advice thanks

 

Actually some class 8 trucks do have syncros, maybe not in the main case but my Mack Visions have them in the secondary. We have one in the shop and looking at the bill from last Feb they had to replace the syncros and the service manager mentioned when it grinds from using the range selector, it is the syncros...

Now the owner is beating up the Stealership so they pro-rate everything they replaced a year ago...

I saw a film from Roadranger about using the clutch where they showed the shock damage from floating gears. They were showing it to students at a truck driving school

I guess I miss that old Mack 5 speed, used to float it all the time! I used to teach guys to double clutch those Macks to ease the shock of tanker loads...

After they finished the shift I told them to just let the clutch up and let the moving driveline ease the liquid back a bit b/4 stepping on the throttle.

Kept them from smacking the back of my head against the back of the cab!

 

if there is shock damage to the drive line, or gear wear from float shifting, I hate to tell you, the driver is not doing it right!

 

I would say I float ~75% of the time, there are instances mainly down shifting I will clutch in neutral rev match and just slip her in gear, i dont think either is right or wrong, if a guy or girl knows how to drive, let them drive. however the correct way is double clutching, so once you learn the correct way you can learn the easy way, I floated on my cdl test, but the cop said "you clearly know what your doing so go this route and bring us back", but I know not everyone has the farm luxury in learning to drive

 

Was going to say,first you still have to match your rpm's. it's funny reading all the new breeders comments, it makes no differance if you use the clutch or not. First it does not wear down the tranny, second you can still get a little grind in there if you double clutch, it's all about the timing and rpm. All this sounds like the young drivers are to afraid to not use the clutch or do not have the self confidence to do so. Also, that is why companies have started using automatics because of the inability of younger drivers wanting to learn to shift with or with out the clutch and are tearing up drivetrains left and right. I do not use the clutch to shift and that truck will shift smoother than any automatic out there,ummm, hay, i guess i've been driving for awhile and have the experiance and confidence to do so. just my .02 worth

 

one other thing i have to question, everyone has been bashing autoshifts. I had a 18918b a\s. thats an 18 speed autoshift with clutch, in my 01 pete with a c-15. As far as smoothness of shifting it didn't get any smoother, always flawless. Except when it was having a bad day and sometimes it wouldn't shift and once in a great while it would SLAM into gear and hard. But i pulled it out and life it good now again with a stick

 

all modern manual transmissions including heavy duty have a syncro system in them..it reduces wear and ear on the trans..ask your dealer/mechanic next time you at the shop

Anything with a splitter has syncros

petey