Ok, so I am a former trucker. Over 400,000 miles behind the wheel of a semi. Driven every type of transmission that has been in a semi. The old two stick Mack. 18 speed, super 10, 13 speed and even the automatic semis you name it, I have driven it. But, I have only driven standard transmission in a car once. And I sucked at it.

In a semi, you have two ways to shift. Double Clutch or no clutch. When I drove, I never clutched, and haven't ground a gear in a long time. Now my dumb question is can I shift a large diesel pickup, like a Ram 3500 with out the clutch? I have heard that you don't have to clutch to shift with a diesel pickup, but I have also heard otherwise. But nothing from a reliable source. I know this is an extremely dumb question. Sorry.

 

as the header says there is no such thing as a dumb question, that said, i gotta ask why would you want to shift minus the clutch? i shift my jeep without the clutch the odd, very odd time, but i always use the clutch, my ram is an auto, so that doesn't pertain to you, but isn't driving a semi with multi speed trans and a four or six speed pickup a bit like comparing apples and oranges, maybe my question is "dumb" also.

 

I was taught to shift without using the clutch in a semi because its easier on the transmission. If you double clutch in a semi all the time, you will be replacing the clutch every 50k miles, if you single clutch you can bet on a new clutch every other month. Yes, an Eaton Fuller 13 speed is a hell of a lot different than a Mopar 5 or 6 speed. I know that you can't do it in a regular car with out the risk of screwing something up. I just didn't know if the same principle applied to larger heavy duty pickups as well. And no, I wouldn't say your question is dumb either.

 

they can be shifted with out using the clutch, however you have to be quite gental when pulling into a gear, otherwise you will pop a syncro, but to light and its gona grind, they can be real pain sometimes, but really its better to use the clutch when shifting these transmissions, its still a lot eaiser to replace a clutch than a syncro, but as long as you dont slip the clutch it will last a very long time

 

Lower rpms and heavier flywheels is why its ok to shift on bigger vehicles as opposed to gassers. Diesel burns slower than gas so it dosent drop the rpms as fast and its easier to synchronize the trans and engine. I say if u can shift without grinding everytime ur not hurting anything, that's what the synchros r for. Now if its difficult to find the rpm and shift smooth then better to use the clutch.

 

I used to shift my old 93 1 ton diesel GMC without the clutch all the time. Never had a problem with it. Just find the butter zone for shifting and remember the RPMS for each gear.

Start off using the clutch to find the proper RPMS to mesh each gear.