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Last night I finally got to take my 41 1.5 ton Chevy (4 speed) out of the driveway!!! It is an all original 41 with 27,000 miles on it. It was parked in a barn most of its life and basically only came out once a year since the mid 80's. I've rebuilt the whole brake system, the fuel system, and the cooling system. Basically I did what I needed to do to get her on the road before it gets to cold to work outside. So anyway heres the problem. At first I just went back and forth down my driveway, 1st gear up, and reverse back down, all was fine. Last minute check out all is good, lets go out for a drive. I started up in Neutral, it grinds into first, second, and so on, all but reverse. So I came home quickly, shut it down looked around, looks good, try again. This time I started it in first. First to second, grind, second to third, no grind. My real confusion is that it doesn't do the same every time. Does anybody have any suggestions, today is beautiful, and I really want to cruise the neighborhood again, but I hope to not grind my way through.

Its going to grind if you shift it like a modern truck. It has no syncros in the transmission. Do a search here and read up on how to double clutch. You also shouldn't have to use 1st gear to start out. Its way low and 2nd works just fine. Good Luck and with some practice you'll be shifting smooth.

Shifting a non-synchronized transmission is a lost art. It takes patience and practice.

Thanks for the help guys, I'm glad to hear that its just me. Practice means I get to drive it, so I'm IN! I'll let you know how it goes, the dog and I are off.
Rob

I've allways had the issuse with my 46 COE of grinding. Double clutching does't seem to help with mine, especially after it's warmed up,the ownly thing that does help is matching the engine RPM to rolling speed. And with no syncros there is no down shifting at all. (I have all new clutch parts installed) Any input would be appreciated. Oh and Hotrod A good luck on your maiden voyage

The first thing is learning to match your rpm with your road speed. I was taught to hold the gear shift with 2 fingers, the thumb and middle finger. That way you can "feel" when the gears will mesh. Modern manual transmissions in over the road trucks still have no synchros. I find it much easier to feel when the gears will mesh without using the clutch.

timing is everything when you downshift you have to burp the accelerator while going thru neutral to bring engine speed up to match transmission speed. crenwelge's two finger method might help avoid tendency to try and force it in gear.engine rpm- correct gear-road speed-timing takes patience and practice.

Rob, I can remember being in the exact same situation as you are when I got my truck on the road back in 2003. I was sure there was something wrong with the truck even though everything on it was new or rebuilt. I can also remember posting here on the site with my shifting woes and being schooled by the veterans. They told me the same things that these guys are saying. I know its frustrating because you want to cruise down the road and go through the gears. I probably only have about 1200 miles on my truck since then and can shift pretty good now. Every once in a while I will rush a shift and it will let me know. One thing I found that really helps is to slow your shift way down. My only previous experience driving manual transmission was in modern vehicles so learning to slow down was hard. You will get it, just keep at it. Try to find some nice flat roads or even a big empty parking lot where you can practice without impatient moterist behind you. As far as down shifting, I can go from 4th to 3rd easy but don't really try to drop to 2nd.
Good luck and have fun!
Bill

Now I know where the phrase "If you can't find 'em, grind 'em" came from! Oscar (the dog) and I spent the better part of the day bouncing down the roads around my neighborhood, no plates mind you. It was wonderful, I read some stuff here on stovebolt, went out and practiced. After a few rounds I think I got the hang of it. Biggest part is to relax and take my time. Thank you everybody for the advice, it is a lost art, and I know why.
Rob

Hey guys: I appreciate all the shifting info and I'm sure Hotrod A does too

Would suggest going ahead getting your tags. Back in the late eightys when I first put my 38 on the road It was about 7:30 pm full dark when I decide everything was good for test run. I had insurance but hadn't gotten tags. Took off got about 1.5 miles from home a car backed out of driveway without looking or didn't give a darn had to come to full stop just barely avoided car. If I had hit them I would have been considered at fault as I had no business on the road without tags. Peoples driving skills and attitudes have not improved in the last 20 years. Ambulance chasers specialize in blaming everyone but those that actually cause the problem.

You might want to put about 500lbs in the bed. With a little weight in the truck things will smooth out some and make it easier for you.

It took me two months and 250 miles to become confident with shifting my '52 2-ton. I depress the clutch pedal to pull it out of 1st gear, but the stick will rarely shift into 2nd until I let the clutch out - then it drops in smoothly. Second to 3rd is a normal shift. Shifting from 3rd to 4th requires a double-clutch. I can downshift from 4th to 3rd without needing a double-clutch. Downshifting from 3rd to 2nd can only be done at a very slow ground speed.

My two young sons still cover their ears when I shift - they don't like the "scary" sound when it grinds. They've asked if our truck is "broken"!

1st gear is so low that you shouldn't have to use it other than if you have a big load or want to just creep along. It sounds like you have a bad sychro if you can't shift into 4th from 3rd using the clutch. I believe that a '52 sm420 should have syncro's in it.

Good advice, as always, guys. To avoid the "coffee grinder" event, practice will make closer to perfect. The whole process (well described herein) requires that "feel" that you will soon take for granted.

Report back to the gurus and experts frequently.

Hey guys, I just wanted to give all of you who helped me an update. You were right, it was me, not the truck! Actually I'd rather it be me, its cheaper that way. I've been all over my town this weekend in the '41, it was fantastic! I think I really only had a couple of embarrassing grinds, otherwise, I stuck to the backroads where I knew I could take my time and feel my way around (the tranny that is). Anyway, thank you all for the support.
Rob

Glad to hear that. It's a wonerful feelin isn't it?

Cool glad you're getting the hang of it. the fellow that wound up with my 54 wrecker got it together and tagged last week stopped by to look a the results. He let me take a spin a blast.

I drive modern trucks for a living. The best description I can think of for learning to shift is to unload the transmission gears when shifting. In modern cars, folks (including me) accelerate continuously, then as soon as you touch the clutch, release the accelerator completely. That doesn't work in a truck. Accelerate, then level off or lightly ease up on the accelerator when you begin to gently pull on the shifter. You will feel the point where the load on the gears eases enough to smoothly pull out of gear. Keep the rpms fairly steady and it should ease on into the next gear. Again, some trucks may like a little more or less rpm drop between, but you'll get the idea.

I have a canadian made 1.5 ton, 1947 AD. It has straight cut gears, no synchro at all. Its off the road for the full rstore so i have never driven it. When did SM420's come out? Mine has the pull up lever for selecting reverse. I'm told this was the pre-47 box, but I have bought another box recently locally (New Zealand) and they are both the same, and date codes are 1968 and 1962. Maybe the export models got the cheapo box.

Double clutching, as my Dad showed me: clutch in, gearlever to neutral. Clutch out, rev engine to match next gear (this gets the engine side of the box at the gearspeed that will be needed for the engagement). Clutch in, slap into gear, make it engage and dont pussy around. Clutch out. I had a '56 rover ages ago with no synchro in first, this was the process every time.

My experience has been that revving the engine is not needed when upshifting--just let the clutch out and step on it again. But when downshifting, you need to rev up the engine to get everything turning at the same speed.
That was how we did it in the 46 pickup my Dad had--also in the 56 Binder I have now.

I'm with Rich, If you need to upshift its because you are "revving" the engine. With my 41 at least upshifts have become quite easy, like I've been doing it forever (mind you I've got about 300 miles on it since I started this post). Down shifting isn't quite as easy, seems like I'm always at too high a rpm, so I need to plan ahead more and slow sooner to be prepared for the down shift. My real problem is that if I start the truck in neutral, it doesn't want to go into gear. If I start the truck in first or second, all is fine. Any suggestions, I guess its not really a problem, its just a little annoying.
Thanks guys and I hope you all have a good thanksgiving!
Rob

It sounds like the clutch is dragging a bit- either try adjusting it, or its got overheated at some stage and warped the friction plate.

47 AD chevys still had lockout lever for reverse, 48 first year for spring loaded reverse lockout.

Think about each shift as 2 motions. Shift to neutral, then neutral to the next gear. Shift,neutral and gear. A old timer taught me this years ago. Its a good way to shift slower.

When I first started driving a "crashbox"(1951 Ford F-5)daily,I had to learn the procedure. All my friends talked about double clutching it,and I did that for a while,but as I got used to the truck,I got lazy,and "half clutched" it. Wind it up in gear,feather the engine speed,pull it into neutral,let the rpms drop just a little slowly,stab the clutch,ease it into the next higher gear,release the clutch and accelerate. Downshifting,decellerate,give it just enough throttle to unload the gears,pull it into neutral,jazz the throttle a little (This part will take some practice,to get enough revs without overshooting your gear-match),poke the clutch in,shift down,a little gently,release the clutch,lift off the throttle and let the engine's compression slow you down,repeat as necessary. Like these guys say,it's all about timing and developing a feel for the truck. Once you drive it for a few months,it's so easy you don't even think about it anymore,and you'll catch yourself even driving the newer trucks that way just from habit. BTW-be sure you leave yourself plenty of room up ahead so you don't have to hurry a downshift or get your timing messed up from a slow vehicle in your way.
Speed