3126 w/10spd Shift Points

[P51bombay]

Well it looks like I may have to try driving this T300 before getting some lessons on shifting a 10 speed, there's only about 10 potential stops between the dealer and where I need to get it for an inspection and traffic should be minimal on a weekend.

I know the procedure, 1 through 5 - preselect - and repeat, and the 6 speed synchro I drive now needs double clutching to get from 1st to second so I can sort of double clutch but do admit to needing more practice.

So what's going to be the easiest, float or double clutch and what are the shift points both up and down? Its a 3126-250 and I think an eaton 10spd.

 

[P51bombay]

Also, am I correct in thinking that in any given gear there is 1 gears available above or below that can be selected without making hamburger?

 

[piper1]

you will likely want to double clutch until you can learn the happy points and shift without the clutch. Most 10 speeds have about 33% steps in between the gears. This would likely translate into something like rev it to 2200 shift and it should land in the 1900 ish range. Depends on the exact set up.

 

[highway star]

It's possible to skip gears, but don't even worry about that until you become accustomed to the trans. There isn't one particular shift point. As Piper says, the important thing is the proper timing in your shifts, although shift points are important for fuel economy. Remember, you're not in a race! Go easy on the gas pedal. Less is more...

 

[Suds43]

I was taught a LONG time ago that you "up-shift" between 1900 and 2100, "down-shift" no lower than 1800.
Just get out and practice, see what the truck likes. Sure, your going to grind once in awhile until you get to know what it likes .lol but before you know it, you won't even be watching your tach, you'll know when to shift just from the sound. You'll be dropping into gear with the pros.
Practice, Practice, Practice.
You didn't say if this was a straight 10 speed, or a super 10. Super 10 is alot easier, you don't have to worry about clutching.
But I'd suggest you double clutch for awhile, at least until you get to know the ghosts and gobblins of the beast.
Good Luck

 

[kwexpress]

maybe its different with my tractor but I always practice progressive shifting.
do an internet search.

i shift at 1600-1650 max I have an eaton 10 speed its simple.
float the gears rev to 1600 then it should drop right in.you will save fuel just try it and see.

 

[kwexpress]

straight from detroit





PROGRESSIVE SHIFT
The Progressive Shift option offers a high range maximum vehicle speed limit to encourage the use
of high (top) gear during cruise operation. Progressive Shift encourages the driver to upshift from
a lower to a higher gear prior to reaching the engine's governed speed. The resulting lower engine
speed in high range should result in improved fuel economy. Progressive shifting techniques
should be practiced by every driver, but can be forced if fleet management considers it necessary.
The benefits from progressive shifting are best realized during stop-and-go driving cycles.
The maximum engine speed will be limited below the programmed MPH to encourage up shifting.
Progressive Shift should be used in applications where the reduced driveability will not
impede trip times or productivity.
Progressive Shift is not compatible with most automatic transmission.
5.15.1 OPERATION
The Progressive Shift option has a setable gear ratio threshold and engine speed limit parameters,
which are programmable with minidiag2. The example shift pattern chart (see Figure 5-16)
reflects default values when the Progressive Shift option is chosen and the gear threshold and
engine speed limit parameters are modified to a typical value.
Figure 5

 

[P51bombay]

Thanks all for the tips, hopefully it won't be too hard to get down the road. As mentioned its a weekend, only about 10 potential stops steady speed in between and about 15 miles to get it to the mechanic for a looksee. The 3126 with 6 speed I drive now I try to apply that progressive method as mentioned, rev just enough to get in the next gear and it seems to like that - usually I shift it around 1700-1800, maybe a little less if going downhill. Sounds like a fancy name for short shifting IMO.

 

[kwexpress]

Thanks all for the tips, hopefully it won't be too hard to get down the road. As mentioned its a weekend, only about 10 potential stops steady speed in between and about 15 miles to get it to the mechanic for a looksee. The 3126 with 6 speed I drive now I try to apply that progressive method as mentioned, rev just enough to get in the next gear and it seems to like that - usually I shift it around 1700-1800, maybe a little less if going downhill. Sounds like a fancy name for short shifting IMO.

what ever you want to call it it will save you fuel

 

[P51bombay]

Well after a bit of playing with it in the industrial park around the dealer I mananged to get it the 15 miles for inspection and back - was already starting to feel more comfortable on the way back. Watching the mechanic drive and give a few quick tips on his short test drive. Most times clutch less shifts were easier, up shifts not to bad considering the only instruction I has was here and youtube - downshifts?.............."needs work" although I did manage the odd one on the way back but most times if I tried and failed it was time to come to a stop and start over. Piper was right on the mark, it doesn't like shifting below 2000 at all - maybe with more practice, practice, practice. I wonder if I should get one of them gearmaster things - seems good in theory, anyone used one?


Truck checked out pretty good for the most part, a few minor issues with the box, drive axle u-bolts need to be re torqued, one rear brake out of adjustment, flex pipe needs changing in the next few months, one or both steers causing a shimmy/vibration around 65kmh and above, tiny chip in windshield,, trans and diff due for oil change and rail gate lift is a touch rusty, (seems Waltco didn't prep so good before paint)and the T&G floor really should be replaced since the surface is breaking up in quite a few places. They are asking $26K CAD so at todays rate around $20775 US. Mileage is 187K. Here's a few pix.

 

[P51bombay]

A few others

 

[TJ959]

I used to moonlight delivering flowers in a 10 wheel truck equipped with a 3126 and a 10 speed. It took a while to get the feel of the thing. Most Detroits and Cummins you can shift at lower RPMs but that little Cat was different. You had to be up above 2000 RPM to shift up or down. It was really hard on the ego to have to come to a stop and start over a few times before I found the sweet spot. It was fine when I got the hang of it.