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The three stick Mack


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Saw the K 12 video before, just caught the "ether injection" system! Hilarious! These guys are like the old street rod builders Barney Navarro, Joaquin Arnette, (gas welded a blown piston in the engine at El Mirage!) They broke the mold! What a loss, all of them! And only  3percent of Americans of driving age can drive a standard shift!

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  • 4 years later...

I've driven  all-most every trans. that Mack has put out. the 3 stick . Has on the inside next to the driver a 2 speed. Hi, Low. Next stick is the 4 speed splitter. next stick, 5 speed main .The 2 speed is used for Low off road. Hi  Highway use. The last Mack that had it was a 1962 B77 with a LTJ cab 320 wheel base. 300 Cummins. 6/29 rears     KAD-Have wrench will travel 

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The problem you get into with multiple boxes is that some of the gears are duplicates.  And, if you're not careful, you end up doing a shift that isn't really necessary.

I like the looks of those 2 that appear to be factory 3-stick setups.  From what I can see, they both look like Duplex transmissions with what is essentially the auxiliary section of a Triplex stuck behind it.  Pretty awesome.

In reality, the 13-speed double-over Triplex and the 18-speed double-over Quadruplex don't leave too many holes in the pattern!

Like Freightrain said, the best use of the third stick is to add a lower and higher gear at the ends of the range.  Most of the ones in the middle won't get used regularly.  Like he said, they are pretty much redundant ratios.  But, the extra low and the extra overdrive could really come in handy...depending on what the front box is.

Still, the more sticks, the better!  I think 2 should be mandatory on a Mack.  The third one just makes it that much cooler.

I drove a 9-speed Unishift once.  Frankly, I preferred the 2-stick Duplex version.  Not too much left to chance when you have an actual stick to stir those cogs!

"Eagles may soar, but weasels don't get sucked into jet engines."

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On 5/13/2017 at 4:55 AM, Freightrain said:

I've seen pics of a few Macks with three sticks.  I have three sticks in my B61.  It's a triplex and I put a 4spd aux behind it when I stretched the truck.

The 4spd is run in Direct for the most part.  The ratio's are the same as the compound so it is redundant if you try to shift it going down the road. I use it for the deep under and the extra OD on the highway.

 

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Why the razor blade, Train?  Not thinkin' of slittin' your wrist, are you?

"Eagles may soar, but weasels don't get sucked into jet engines."

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  • 1 year later...

May be it is the angle of the  picture, but it looks like stick placement is in the way of the pedals! My Marmon has a Eaton 15/OD (12 useable) coupled to a set of tandem 2 spds.  More gears then necessary but nice, esp when moving big loads. Some of the 12 front ratios can be duplicated with the 2 spd, so I didn't use all 24 possible. Generally started with the rears in low range (normal reduction) and once I hit 45 or so hit high range, climbing hills I would drop 2 gears in high then switch to low. Deep reduction was only used to start on soft ground or for maneuvering heavy loads in tight spaces.

Edited by Geoff Weeks
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Geoff you are correct about the “ Brownie “ box shifter being directly behind the fuel pedal,, it came factory with this setup according to the original owners son,, I’m unsure if this was common back then with Mack’s , it was originally a log truck sent to Northern California. Dan Thomas has the Sister truck ( 1 serial number newer) I’m unsure what transmission setup his has, it was on the cover of Wheels of Time last year. ( Note the 8 track radio under the glove box,, it was a early 70s restoration) 

Edited by 1961H67
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It certainly takes getting used to, Mine are size 12 , and with steel toe work boots you can’t just slip your foot from fuel to brake, kinda have to lift it and set it back , but I think the picture does show it closer than what it is,, but it is still a little tricky.  I’ll try to find a closer picture, I’ll start paying attention to other trucks with that 3 speed auxiliary. 

IMG_4081.jpeg

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  • 2 months later...
On 5/15/2017 at 12:18 PM, AZB755V8 said:

It would be Great to see another B71 out at shows. I have only seen one at at the Oregon ATHS show a few years ago.

Looking at the photos it is about as original as you are going to fine and is not rusted or dented to hell. Being new to old Macks i hope you have a lot of hands on mechanical experience, aware that everything is big and heavy. and have a very large bank account to get a restoration to the finish line.

It is definitely a low production B with the Cunnings, 3 stick and has been sitting for year. It will not be going anywhere fast if the price is $25K. Before you go Mack crazy and buy it contact Dan Thomas (Mackdaddy) in Oregon he has and knows of a lot of trucks worth something in that area. His restored trucks are second to none, he may even have what you are looking for, super nice guy. I know he had a 3 stick LT with a 275 Cummins, in restoration, that he was selling awhile back. 

Just a side note, It is cool to have a lot of gears but after the novelty of driving it and shifting every 10 seconds wears off you will be driving it with the Duplex ad shifting the Brownie from direct to high for the second overdrive only.  There are no synchro's in any of these trans and it takes a lot of practice to fell the gears in and not blow a shift and grind. Get two sticks in natural at the same time, pull over to a Complete STOP and start over:rolleyes: 

That called DOUBLE NOTHING 😂 😂 

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time killing on craigslist  under mack truck title ; appears to be a B-model Mack out west area having a 3 stick combo. supposably earliest (first ?) B made.  bounced so many states don't remember which one .  went to far side of country due to fact same posts are in every area close by. 

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