Mack 12 Speed

[sodly]

Most all the trucks I ever drove had Fuller 13 speeds.  But I'm intrigued by the Mack 12 speed transmission.  I've watched several videos online showing how they work so I think I generally understand it.  Could anyone offer a comparison between driving the 13 speed and the 12 speed Mack?  I've heard some people say the 12 speed is a "love-it-or-hate-it" transmission.  Why is that?  And I've heard people say that if you're used to a 13 speed you'll have trouble adjusting to the 12 speed Mack.  Any truth to these rumors?  I've always heard good things about the Mack transmissions.  Would love to try one sometime.  Hopefully someday I'll get a chance.  

[mrsmackpaul]

The 12 speed I feel is the greatest gear box ever built. The road ranger is a lot more work to drive and isn't as well designed. It's harder on the driver and more thinking is involved if you arent used to it, where as the Mack is pretty fool proof. I am a fool and seem to handle it.

The road ranger you have to shift the stick for every change. Macks you don't.

The biggest thing I have found in driving a Mack box is you can't race them. There's a lot of weight spinning on the three shafts so I need to take my time.

I have never had any luck driving a Mack with out a clutch. The Road Ranger is easier to shift not using a clutch at least I find it is.

You get 5 reverse gears in a Mack box, only one in a Road Ranger. When hauling sugar cane, we often split into high range in reverse but it is easy to break reverse out the side on a Road Ranger box. Have seen it happen a few times.

Biggest down side to the Maxitorque box is the shape. It's a bugger of a thing to pull out if your not set up for it but they are that tough they rarely have to come out.

Paul

[TeamsterGrrrl]

Splitter boxes like the Mack 12 speed simply make sense... Even if you're using every gear, you're only moving the lever for half the shifts. Splitter boxes also make it easier to skip shift when running light- For example, with an 8V-71 hauling bread with a Spicer 10 speed splitter box I'd start in 1st or even 2nd high and go up in full gears, only splitting in top gear (5th).

[Timmyb]

I personally find the Mack 12 speed to be a lot noisier. My old mans one has a whine once it gets a bit higher in speed. Also a bit more noise when changing. 

Not as many gears as your 13 speed. Definitely try it if you get a chance. 

[mackey58]

Never drove a 12 speed so you 1st direct then 1st high.and so on .not 1-5 direct then 1-5 high

[tjc transport]

mack 12 speed shifts just like a 5 speed trans with 2 speed rear.

pretty much idiot proof. unless of course you are an idiot.

[mackey58]

Lol nice the 88 lowboy tractor had thst with the dash switch but never  got to drI've that one just the 9 speed and 7 speed

[sodly]

13 hours ago, mrsmackpaul said:

The road ranger you have to shift the stick for every change. Macks you don't.

I have never had any luck driving a Mack with out a clutch. The Road Ranger is easier to shift not using a clutch at least I find it is.

Paul

Hmmm.  On all the Roadranger 13 speeds I drove you really only used 12 of the gears.  1st was basically granny low so you'd normally always start in 2nd.  But you did not move the shifter for each shift.  You move the shifter for the first 4 gears then pop it into high range and run through the 4 positions again.  However in high range you could split each gear with the thumb switch (giving a total of 12 gears).  I never used the clutch except to start/stop on the Roadrangers.  

Do you have to clutch each shift on a Mack 12 speed?!  Uuugh.  Hope that's not the case.  That would be a major turn-off.

[terry]

32 minutes ago, sodly said:

Hmmm.  On all the Roadranger 13 speeds I drove you really only used 12 of the gears.  1st was basically granny low so you'd normally always start in 2nd.  But you did not move the shifter for each shift.  You move the shifter for the first 4 gears then pop it into high range and run through the 4 positions again.  However in high range you could split each gear with the thumb switch (giving a total of 12 gears).  I never used the clutch except to start/stop on the Roadrangers.  

Do you have to clutch each shift on a Mack 12 speed?!  Uuugh.  Hope that's not the case.  That would be a major turn-off.

No. If you have shifted a mack 5 speed you can shift a 12 speed.

Edited August 11, 2016 by terry

[GOOG]

I have two 12 speeds, and to be honest, It isn't my favorite.  You can't preselect in the lower gears. You can't get into fifth gear without a little crunch from the air shift. I don't use the clutch.   Look at it like a five speed with a two speed rear.  You can (but don't have to) split every gear.  In my opinion, the 18 speed is hands down the best transmission you can put in a truck.  The 13 speed is right behind it.  The biggest benefit to a 12 speed, is that you have 5 speed in reverse.  Another huge drawback is not many drivers have 12 speed experience, I don't like teaching people to drive in my trucks. 

 

[mrsmackpaul]

7 hours ago, sodly said:

Hmmm.  On all the Roadranger 13 speeds I drove you really only used 12 of the gears.  1st was basically granny low so you'd normally always start in 2nd.  But you did not move the shifter for each shift.  You move the shifter for the first 4 gears then pop it into high range and run through the 4 positions again.  However in high range you could split each gear with the thumb switch (giving a total of 12 gears).  I never used the clutch except to start/stop on the Roadrangers.  

Do you have to clutch each shift on a Mack 12 speed?!  Uuugh.  Hope that's not the case.  That would be a major turn-off.

every road ranger I have driven wont shift until the gear stick passes thru the neutral gate in the box except for deep reduction can be shifted on the go with just a flick of the throttle and the switch  

I never have used all 12 speeds in a the Mack most times maybe 5 or 6 speeds only unless the weight is getting up to over 40 tons then I may split 4 th and 5 th once you go above 60 tons I find 3rd 4th and 5th need to be split even taking off on a steep hill with big weights lift off in deep reduction then low 1, 2, 3 and split after that  

But with a Mack motor even a cool powered Thermodyne they pull like a train so I find a lot of the time I will drive them just like a Maxidyne fine 

Paul

[harrybarbon]

Please what is the difference between the Mack 10 speed overdrive and the 12 speed overdrive boxes - is it only the 2 deep reduction gears?

What difference is there between an E6 - 350 with a 12 speed overdrive versus a E6 - 350 with the 10 speed overdrive? 

[terry]

3 hours ago, harrybarbon said:

Please what is the difference between the Mack 10 speed overdrive and the 12 speed overdrive boxes - is it only the 2 deep reduction gears?

What difference is there between an E6 - 350 with a 12 speed overdrive versus a E6 - 350 with the 10 speed overdrive? 

If you are talking both 107 series trannys, they are the same except the 12 spd. has two lower creeper gears.    terry

[Yoos Brothers Construction]

Just my 2 cents but I really love Mack 12 speeds! The truck I drive right now has a Mack 13 speed in it and frankly I hate it compared to the 12. Don't get me wrong the 13 and 18s are nice But I'm not the biggest fan of the them. Like I said just my 2 cents. Every body at work thinks I'm nuts but I can shift a 12 speed faster and do the same work as the 18 speeds plus the 12 speeds have a really nice low hole.

 

Thanks, Josh

[sodly]

21 hours ago, GOOG said:

I have two 12 speeds, and to be honest, It isn't my favorite.  You can't preselect in the lower gears. You can't get into fifth gear without a little crunch from the air shift. I don't use the clutch.   

 

Yikes!  You can't pre-select the thumb switch on a 12 speed?  I figured surely you could... just like on a RR 13.

I'm not up on Mack 13 speeds.  Hoping to keep this conversation focused on the Mack 12 vs. the Fuller RR 13.  

[Timmyb]

In my dads, when you go from direct to hi is fine. But when you preselect direct before shifting the stick it will sometimes jump back down a gear. This mainly happens in 1st in my dads. 

In other gears it preselects fine. 

[mrsmackpaul]

3 hours ago, Timmyb said:

In my dads, when you go from direct to hi is fine. But when you preselect direct before shifting the stick it will sometimes jump back down a gear. This mainly happens in 1st in my dads. 

In other gears it preselects fine. 

when this happens the air pressure isnt set right 

A soon as you flick the switch on the knob it puts pressure on the fork but the gears will only release when they have no load on them 

so if your climbing a hill and need to split a gear flick the switch when your near ready then on and off the go pedal and it will go straight in 

If your using the gears to slow down with dyna tard (dont know why you would bother open the door will work better) just flick the switch and on and of the go pedal they change right away 

The only time they will slip into neutral is when the engine gets down to near idle 

The reason you can preselect a Road Ranger is because they wont complete a change till they pass thru the neutral gate then the air is applied to the shift rams

the Mack box is noisier but there is a lot more moving in a Mack box than a Road Ranger 

Think about this the Maxi torque was built for 285 hp it was that well built it was almost unchanged in basic design for way over 600 hp of the E9 thats Mack tough and on road trains they get over a million miles on the maxi torque grossing over 115 ton every day of their life you will never get that kind of life out of a road ranger  

Paul

[GOOG]

I hit the air shifter after I make neutral, going from 1st to 2nd.  I usually preselect going from 2nd to 3rd. If you keep a little pressure on the shifter it works fine and will air shift as you shift manually.  If you don't keep enough pressure on the lever the air shifter will down shift about as violent as an earthquake.  The other shifts are much easier.  My 18 speed is effortless and easy.  A gear for every occasion.  There is no comparison.  I am going to swap the 12 in my Superliner for an 18 at some point in the future. 

[Swishy]

Here B the §wish do n sum gear lapp n

Clikity .................................................ClikClikClik

 

2 problems

<1> the Dynatard hangs on n wont release all the time (fix: New relay fiited)

<2> The clutch is a bit grabby n wont slo the gears down when start n off (Solve problem: Clunk the gear lever into 1st The biggest meanest cog in the box to slo the gears down then grab the desired gear for lift off

 

cya

§wishy

 

[Underdog]

That's all well and good Swishy thanks for the tutorial, but let's see ya do it with your right hand...

Had the 10 speed version in my E9 Superliner, I vote the most enjoyable truck to drive. 5 reverse gears and 5 PTO speeds very handy for dump work.

[bulldogbred]

I have a 12 speed in my RS700L. Mine is the older one I have a separate stick for Low Low not the air shift on dash. We have a couple RD's with 8LL. Had a CL with 18 speed once. Several 2 stick 6 speeds. A triplex. A quad box. Another R model with a 12 speed with the air shift on the dash for low. A superliner with a Mack 1070 10 speed (same as 12 speed without low). A value liner with a 13 speed road ranger. 

Having drove pretty much every trans you can get in a Mack except the brand new ones. I personally love my 12 speed. I don't have to shift a lot. Multi speed reverse is great. I love being able to set my PTO speed how I want for running dump trailer or lowboy. I honestly don't know why Mack didn't sell more of them.