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jackndabox

5+4 Transmission Shifting

19 posts in this topic

Hello All

I am looking to buy a R model. Always have liked Macks but never had the money to buy one, but now I do. Can spend about 5k. In regard to the 5+4 transmission. Is it possible to shift the 5+4 as only a 5 speed. Are all the 5+4 made by Mack. I really want a truck that is ALL Mack. Thanks

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Hello All

I am looking to buy a R model. Always have liked Macks but never had the money to buy one, but now I do. Can spend about 5k. In regard to the 5+4 transmission. Is it possible to shift the 5+4 as only a 5 speed. Are all the 5+4 made by Mack. I really want a truck that is ALL Mack. Thanks

not really-maybe if you were bobtailing all the time. a quadruplex isn't that hard to drive after you fool with it a while-under,direct,and over in the compound in each gear in the main until you get to 5th.gear,then you don't use the compound.The quad. is a Mack trans. but not all 5 and 4s are.

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Yes, I've done it many times only when I was M/T. If it's LoLo,Low, Direct & Over, just leave your aux. in direct shift your main trans. progressivly to 5th if the truck is too slow in 5th direct then shift your aux. into overdrive. I've driven A-Cars Macks & Crane Carriers with 10 to 15 yd concrete mixers for Colonial Sand & Stone and after we unloaded we didn't need all of those Xtra gears you can do the same with a duplex & a triplex just makes your day a little e/z/er

Ernie

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Hello All

I am looking to buy a R model. Always have liked Macks but never had the money to buy one, but now I do. Can spend about 5k. In regard to the 5+4 transmission. Is it possible to shift the 5+4 as only a 5 speed. Are all the 5+4 made by Mack. I really want a truck that is ALL Mack. Thanks

Mastering the Quadraplex (5 x 4) is a badge of pride not a lot of drivers can carry . Not for the lazy or faint of heart. But then neither is a real Mack . A real driver is the guy who can go down the road with 42 ton in a sand box shiftin a 4 by drinkin a cup of coffee smokin a cigarette and talkin to you while cussin the traffic and readin the address on the delivery ticket and still doesent grind a gear or miss a shift .

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Mastering the Quadraplex (5 x 4) is a badge of pride not a lot of drivers can carry . Not for the lazy or faint of heart. But then neither is a real Mack . A real driver is the guy who can go down the road with 42 ton in a sand box shiftin a 4 by drinkin a cup of coffee smokin a cigarette and talkin to you while cussin the traffic and readin the address on the delivery ticket and still doesent grind a gear or miss a shift .

I'll agree with that. I always said it takes way more skill to drive a 5 speed Mack than any of the roadranger transmissions.

If you drive a quadruplex like a 5 speed you must have way more horsepowers than my B-model's got.

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The thing is, it's impossible to keep a Thermodyne engine in it's proper operating range of 1500 to 2100 RPM if you just shift it like a 5 speed. Lugging a Thermodyne below 1500 will ensure it's early demise. That was the reason those transmissions were used behind those engines.

Once you get the hang of it, it's posible to shift it very smoothly, just about like an automatic, both upshifting and downshifting, one handed or two handed.

.

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The guy asked A question?can you drive a Mack with a quad box without using all the gears and the answer is YES if you are M/T and the truck is NOT loaded I stand by my answer! it has nothing to do about being lazy or driving with two cups of coffee and 4donuts and a pack af camels if your 673 natural or your E9 500 can" t pick the RPM'S up M/T you should bring it to the shop if the quadbox has a dead 5th then you can't shift it that way

Ernie PS sorry not trying to be a wise guy just thought i answered the guys question correctly

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The guy asked A question?can you drive a Mack with a quad box without using all the gears and the answer is YES if you are M/T and the truck is NOT loaded I stand by my answer! it has nothing to do about being lazy or driving with two cups of coffee and 4donuts and a pack af camels if your 673 natural or your E9 500 can" t pick the RPM'S up M/T you should bring it to the shop if the quadbox has a dead 5th then you can't shift it that way

Ernie PS sorry not trying to be a wise guy just thought i answered the guys question correctly

Relax Ernie!!!!!!!!!!!!

The point I was trying to make is that with those old engines they must be kept in the 1500 to 2100 range when pulling. Of course with an empty truck lots of gear combinations can be omitted and the engine will still be able to accelerate without lugging, but as a former quad box driver I'm sure you know as well as I do that a loaded truck in those east coast hills requires most of the gear combinations in a quad box to be used properly.

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Took power nap,I am relaxed an cured of any egotistic tendancies no offense taken HK I just love this site and it answers so many unanswered questions that i have,

and so many more to come!!

ERNIE

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everybody just calm the f*** down!..that's better.

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everybody just calm the f*** down!..that's better.

I HAVE A LOT OF RESPECT FOR THE GUYS THAT CAN DRIVE A QUAD GOOD. I WAS TO YOUNG TO BE ABLE TO LEARN THAT . MY FATHER WAS ABLE TO MASTER THAT IN THE 71 DM607, BUT I WAS ONLY 14 WHEN THE TRUCK WAS TAKEN OFF THE ROAD FOR THE NEW 89 DM 690 WITH A 2080 TRANS, THEY ARE TERRIBLE TRANS.HE WAS ABLE TO PULL ANY GRADE WITH ANY LOAD, I WOULD STILL LOVE TO MASTER THAT. WHAT WAS THE HEAVIEST TORQUE RATED QUAD OUT THERE.

I AM ABLE TO DRINK COFFEE, EAT GREASY PIZZA AND SHIFT ALL AT THE SAME TIME, BUT HAVNT MASTERED TALKING ON THE CB AND SMOKIN YET.

GG2

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GG2 hay thers nothing wrong with being to young you can always learn,just got to find A truck with A side stick I'd show you on my Brockway but thats a5x4 air shift besides A Mack I though was always the easiest an just felt like they (the two sticks) belonged together just a better driver friendly truck all around just my opinion. And OH by the way usually when you drove an A-Car with an aux trans there was a peice of rebar under your seat so when you jamed the aux you had to go under the truck and bang the shifting rails back into place something something you didn't have to do on a MACK

ERNIE

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if you horseshoe the aux on the quad you will need a long screwdriver to un stick the shafts on the aux box too if the shifter is worn...joe

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GG2 hay thers nothing wrong with being to young you can always learn,just got to find A truck with A side stick I'd show you on my Brockway but thats a5x4 air shift besides A Mack I though was always the easiest an just felt like they (the two sticks) belonged together just a better driver friendly truck all around just my opinion. And OH by the way usually when you drove an A-Car with an aux trans there was a peice of rebar under your seat so when you jamed the aux you had to go under the truck and bang the shifting rails back into place something something you didn't have to do on a MACK

ERNIE

THANKS, AND YES YOU DID HAVE TO DO THAT ON A MACK, THE OLD 71 WOULD JAM AND YOU WOULD HAVE TO RAISE THE BODY AND USE A CROW BAR THE UNJAM THE BOX.

WOULD BE FUN TO HAVE A QUAD IN A MACK WITH A V-8 AND OPEN PIPES, I LOVE TO MAKE NOISE

GG2 PS.. BULLHUSK, DID WHAT YOU SUGGESTED WITH THE BROCKS.

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Hello All

I am looking to buy a R model. Always have liked Macks but never had the money to buy one, but now I do. Can spend about 5k. In regard to the 5+4 transmission. Is it possible to shift the 5+4 as only a 5 speed. Are all the 5+4 made by Mack. I really want a truck that is ALL Mack. Thanks

I may skip a gear on mine every now and then empty, and sometimes even loaded if I just broke over a rise or something, just depends on the moment and whether i can keep RPMs reasonably good, have to agree with HK, dont be lugging too much or you will pay for it later, all works better to maintain that RPM band...Randy

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Ya GG2 good luck wtth them Brocks.You should get some hits there and you know I never had that happen to me on a Mack but I learned on a Mack Quad box and the old timer (Tony) would always tell me make square shifts and no horseshoe's like Joe said

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Quoting from an article at "http://www.dieselpowermag.com/news/0707dp_1973_maxidyne_300_series_mack_engine/index.html". "The Mack Advantage

In 1966, the company was suffering from a lack of capital, but the new Maxidyne ENDT-675 diesel series was introduced with great fanfare. This novel engine produced 237 hp with peak torque at 1,200 rpm and delivered a usable powerband up to 2,100 rpm. This was a huge innovation because Mack offered a mill with a 52 percent torque rise (torque rise is peak torque divided by torque at rated horsepower). No big deal, you say? Consider the competition offerings of a mere 20 percent, and today's versions have an average of 35 percent. Mack engineering provided the low-end grunt by tweaking the mill's internals, modifying the fuel system, and playing with the turbo pressure.

Mack capitalized on its engine's brute-force advantage by producing a five-speed triple countershaft Maxitorque transmission. The idea was intended to make the driver's job easier (less shifting), compared with the competition's 10-13-speed transmissions. This meant a Mack truck traveling at 50 mph in Fifth gear with a heavy load could climb a 6 percent grade with the driver downshifting only one gear. In Fourth gear, the Maxidyne (Maxis) engine could maintain 1,700 rpm, and the truck would crest the grade at 20-25 mph. Maxis were highly regarded in over-the-road, dump-truck, and mixer applications, where low speeds were common and constant shifting was a pain. In 1973, an intercooled ENDT 676 Maxidyne-series engine was introduced. This new unit featured 1,080 lb-ft of torque with 285 hp.".

Is the 5 speed Maxitorque transmission mentioned in this article different from the main Box associated with the Quadraplex. The reason I am asking, the article seams to lead one to believe just the 5 speed was all that was needed.

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Those compound shifter jam ups happen when the bottom end of the stick gets worn down to the point that the stick can get caught between the shift rails when shifted "horseshoe" style.

Easy fix, just take out the stick, weld up the end of it, then grind it down to the original dimensions, re install the stick and no more jam ups. It's always the stick that wears down since the rails are a harder steel than the stick.

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Quoting from an article at "http://www.dieselpowermag.com/news/0707dp_1973_maxidyne_300_series_mack_engine/index.html". "The Mack Advantage

In 1966, the company was suffering from a lack of capital, but the new Maxidyne ENDT-675 diesel series was introduced with great fanfare. This novel engine produced 237 hp with peak torque at 1,200 rpm and delivered a usable powerband up to 2,100 rpm. This was a huge innovation because Mack offered a mill with a 52 percent torque rise (torque rise is peak torque divided by torque at rated horsepower). No big deal, you say? Consider the competition offerings of a mere 20 percent, and today's versions have an average of 35 percent. Mack engineering provided the low-end grunt by tweaking the mill's internals, modifying the fuel system, and playing with the turbo pressure.

Mack capitalized on its engine's brute-force advantage by producing a five-speed triple countershaft Maxitorque transmission. The idea was intended to make the driver's job easier (less shifting), compared with the competition's 10-13-speed transmissions. This meant a Mack truck traveling at 50 mph in Fifth gear with a heavy load could climb a 6 percent grade with the driver downshifting only one gear. In Fourth gear, the Maxidyne (Maxis) engine could maintain 1,700 rpm, and the truck would crest the grade at 20-25 mph. Maxis were highly regarded in over-the-road, dump-truck, and mixer applications, where low speeds were common and constant shifting was a pain. In 1973, an intercooled ENDT 676 Maxidyne-series engine was introduced. This new unit featured 1,080 lb-ft of torque with 285 hp.".

Is the 5 speed Maxitorque transmission mentioned in this article different from the main Box associated with the Quadraplex. The reason I am asking, the article seams to lead one to believe just the 5 speed was all that was needed.

Yes, the Maxitorque 5 & 6 speeds were triple countershaft transmissions as opposed to the single countershaft of the 72/ 722 series of which the quad box was a member.

That article you quoted also references the Maxidyne engines, which had an operating range of 1200 to 2100 RPM. Although the Maxidyne & Thermodyne shared the same block and many other parts, the Thermodyne was not designed to be lugged down below 1500.

I have in the past transplanted Maxidyne engines into quad box equipped trucks with good results, but Mack never offered a Maxidyne engine backed by a quad box from the factory.

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