The Stovebolt Site Forums The Parking Lot Big Bolts 1948 COE 2-ton

Lisa, when you paste text into the text box here from another application you MUST change the dropbox below to "using HTML and UBBCode" or it comes up blank - easier is to just compose your post here directly

Hi red58,
Thank you! I was wondering what happened?
Lisa

long standing bug of the forum software - I'll see if this will add a clickable title, otherwise the only entry is to click on the last post time

nope, only puts the title on in the 'Active Topics'

Bill

Hi,Lisa! If you start out in "direct"(Brownie's 2nd gear),go through all your gears,(SM420). when you reach about 1,800-2000 R.P.M.,push-in the clutch,shift the "Brownie",and the 4-speed to "neutral",(simultaneously as possible),let the clutch out QUICK,depress again,FIRST shift the "Brownie" into 3rd(O.D.),then the SM420,into 2nd.This is called:"Double-Clutching".Gears are not synchronized,and this procedure helps them mesh. You only have about a 10-second window to shift in,otherwise,you'll have to stop,and start over.Better to shift on level ground until you get the "Hang" of it. If you miss a shift like this,you'll have to stop,and start over. Try this in a large parking lot,or "quiet" stretch of roadway,first. Leave the "brownie" in O.D.,and shift the 4- speed like you normally would. Trucks should always use a lower gear,while decending hills,just in case of brake failure. down-shifting would be the reverse: Shift the SM420 from 4th.,to 3rd.,to 2nd.,then '"double-clutch" the "Brownie"/SM420 into neutral then "Direct"("Brownie")/2nd.,(SM420),as simultaneously as possible. They may grind a little,but that's normal. There are a couple of video's on "youtube",but the ones that I've seen have Detroit 3,and 4-cylinder engines,but the same shifting principles. Gives you a good idea of the shifting pattern(s). "1949 Diamond-T 3-53 Detroit Split-Shifting" Hope this helps.

Lisa

You can see videos of guys shifting both boxes simultaneous -- that is fine for someone with experience. For a beginner it just may be a good way to tear up a gearbox.

Try it a bit simpler. Shift only one box at a time. Unloaded you probably will not need the brownie and probably not on hills.

For initial learning I think the Brownie in low is a bit better. Shift just the main for a while until you get comfy with that.

Mistakes ie missed shift are easier to correct in this manner. Do not use the clutch after you get rolling. Shift only using two or three fingers - do NOT jam or force gears. It will easily slide into mesh when the teeth of each gear are spinning at same RPM. If you miss a shift it will take some tinkering (hunt n peck) to find the new gear match.

Then you can get complicated and split shift ie
MAIN BROWNIE
low low
low direct
low over
second under
second direct -- and so on and so on.

When you get really good then you can do it like shown in the videos.

Thank you so much! This is all very helpful! That's why I love this site! Thank you "wetwilly5757"

Lisa

Hi Leitmotif,

Thank you so much! Your advise will be very helpful! I'm definitely a beginner.

Lisa:)