Does anyone double-clutch?

[bassetdeuce]

Not according to the parts manuals that I have seen. Straight cut gears are often used in the lower gears but helical are for the uppers.

Sure, helical for the overdrive and countershaft gears. In truth it varies for each type of trans, and there are many varients.

 

[Somemedic]

The first 4 vehicles I owned were all manual shifts and I learned to speed shift early. I noticed after awhile my jeep would grind between 3-4. Turns out the AX5 synchros arent very stout nor do they take very well to clutchless shifting. Ended up replacing all synchros in the gear box. That wrangler doesnt weigh anywhere near 13k. Nor does it have another axle. After reading the posts from others Ive decided to a) use the clutch and b) start the truck out in 1st gear, everytime. Its hard since I hadnt been doing so in the past but Id rather not drop that tranny and start replacing parts just yet. My ...

 

[Gastrap]

There's no advantage to double clutching a synchro transmission if its working properly, you're just putting needless cycles on parts
Shifting a synchro trans. without clutching is not a good practice. The small teeth of the synchros dont provide a good feel to the operator & those parts are easily damaged.
I shift the deuce as designed & burp the throttle when downshifting to avoid clutch wear.

 

[pwrwagonfire]

I double clutch whenever I drive our deuce and a half...there is so much weight in the back with water and equipment (firetruck), and it shifts MUCH smoother when I do so.

 

[sandcobra164]

I've tried double clutching and it didn't seem to make much of a difference. I use the clutch for all shifts. In mine, 4th will grind if you don't wait around a second to engage and 1st is hard to push out of if you run the rpm's up past about 2200. Not sure about 1st being hard to come out of under those conditions but 4th in mine likely has a weak synchro and I've learned to deal with that short coming. Most Deuce's I've driven in the military are hard to push out of 1st when run hard so I believe that's just the way they are. I could be wrong though, most of the Deuces I've driven were National Guard trucks that didn't get serviced as well as the Active Duty trucks for the most part.

 

[Billy Bobbed]

d**n if you do, d**n if you dont.

 

[5ton4ever]

double clutch

I thought the clutch was so the engine does not stall at stop signs! Just kidding. I have been driving heavy haul trucks for 26 years. sometimes I double clutch, sometimes no clutch just depends on conditions. up hill, down hill, loaded or empty, I will usually double clutch on a steep hill with a heavy load to insure the gears are fully meshed before I put a strain on it. seems to work. Keep your powder dry.

 

[saddamsnightmare]

February 10th, 2010.

Depends on the mood of the truck and the outside temperature.....! My M35A2 does seem a little happier on the shifts when you give it a small blip on the throttle between gears, but I don't have to truely double clutch. The Unimog S404.114 can be a very different animal below 32*F on shifting untill the heavy gear oils reach the upper speed gears. Yesterday it was about 22*F in the early AM, and the Unimog did not want to go from 5th to 6th, untill the oil got well carried up to those gears and warmed up. Normally she is not a problem in any shifts, unless its very cold at night, then there's heck to pay in the morning.
The Unimogs is like a Model T Ford in that it will creep at start up in nuetral on both the transfer and the main shifts, due to the thickness of oil between the gears and pressure plates......
Once its warmed up the bad behavior stops....

Cheers,

Kyle F. McGrogan

 

[mbarber84]

I double-clutch up and down, makes for a smoother ride and is easier on drive train components. Just my 2 cents worth...

 

[FtSill69]

As a CDL holder with 8 years of over the road 13sp & 10sp experience, two years of 10T, 5T, & 2 1/2t and four years of 4x2sp straight grain trucks; I believe you should shift however you have to to make a smooth complete shift, being as easy on equipment as you can be. You may have to walk sooner if you don't.

Worn but still serviceable transmissions will all have a different feel. I have driven some that worked the best after you are rolling, slide shift out of gear, then clutch once into the next gear and one that was just the opposite.