why double clutch istead of floating gears

My clutch went out in Albuquerque and I had to deliver my load in northern California. Became Expert Level 9000 in floating.

 

Huh?
Synchronized truck transmissions are a fairly recent development. I was taught to float gears well before synchronized transmissions were introduced.

From wikipedia:
Heavy-duty transmissions are almost always non-synchromesh. One argument is synchromesh adds weight that could be payload, is one more thing to fail, and drivers spend thousands of hours driving so can take the time to learn to drive efficiently with a non-synchromesh transmission. Heavy-duty trucks driven frequently in city traffic, such as cement mixers, need to be shifted very often and in stop-and-go traffic. Since few heavy-duty transmissions have synchromesh, automatic transmissions are commonly used instead, despite their increased weight, cost, and loss of efficiency. [My edit: based on what I've been told, the last sentence is *probably* outdated. New auto trannys are decreasing in cost and are more fuel efficient than manual transmissions... there is still some debate about that, depending who you talk to.]

Huh???
Are you saying car transmissions aren't synchronized? That's the reason you don't double clutch a car, because the transmissions are synchronized.

https://www.hemmings.com/magazine/hcc/2015/01/Synchromesh-Gearbox/3745481.html

 

Lol!

 

Well @JReding, I appreciate a worldly man of your age to be provide us with your well honed experience because according to your quote:
https://www.hemmings.com/magazine/hcc/2015/01/Synchromesh-Gearbox/3745481.html
"The first synchromesh gearbox was pioneered by General Motors and appeared with the 1928 Cadillac."

You obviously have been doing this 'floating' thing for a long time and I succumb to your vast experience.

 

You will probably float most I think do as I to do.The argument to use the clutch is valid while floating is easier on the clutch it's very hard on the synchronizer gears.And at the end of the day it's much less expensive to replace 2 clutches then 1 transmission

 

Some have said relearning double clutching is like riding a bike. I can still ride a bicycle, think I could pick up double clutching fairly quickly. I drove 238's, 220 and 250's with 10 and 13 speeds. The whine of the 238 was inversely related to it's power.

 

I have a question about shifting since im not a driver yet. Do you press the clutch in first then shift or do you press the clutch in and shift at the same time? When i learned how to drive stick on a car 20 years ago you clutch in then shift, is it the same?

 

Driving a standard car right the clutch should last as long as the vehicle. My first car still had the original clutch in it at 3xx,xxx km.

Tap clutch, shift to neutral. Let RPM fall 300-500 RPM (adjust for up/downhill, load etc). Clutch in enough to break torque and shift into the next gear. Downshift is the same except you bring the RPM up that amount by stepping on the throttle while in neutral.

 

There's a distinction, of course... car synchro vs truck synchro...

 

Ohh, you're one of those people... My friend and coworker is one of you people, too. (I kid!)
He just sold a car he bought new back in 2004, it still has the original brakes on it with 300,000+ miles as well.

Pretty impressive on both counts, if you ask me.