Licensed to kill Posted October 12, 2023 Share Posted October 12, 2023 Did mack make a twin stick 12 speed or only air shift? Quote Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/ Share on other sites More sharing options...
doubleclutchinweasel Posted October 12, 2023 Share Posted October 12, 2023 I don't know of an honest-to-goodness 12-speed 2-stick. But then again, most of my experience is with the "old" (Duplex/Triplex/Quadruplex) stuff. I have seen certain versions of the (overdrive 18-speed) 5 X 4 box called a "14-speed" before. And the overdrive versions of the 5 X 3 units were called "13-speed". But, the only versions of the "real" 12-speed I ever saw were air shifted. You have a knack for coming up with intriguing questions, don't you! I'll be curious to see what comes of this one. Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540117 Share on other sites More sharing options...
Licensed to kill Posted October 12, 2023 Author Share Posted October 12, 2023 The reason I am asking is that I picked up some parts yesterday from a guy that used to own a Mack dealership through the 70's and 80's (and is restoring a B-61) and told him what I was doing. When I mentioned that I am using an E-6 350 with a twin stick 6 spd, he thought for a bit then said, "that won't work". I said "what do you mean" he said " E-6 350 is an econodyne and the 6spd was made for the Maxidyne. That engines torque curve is not suitable to the 6 Spd trans. You will NOT like that at all. The econodyne needs more gears to be happy". So, I researched that and, sure enough, it appears that he was right. SO, I did some checking and find that the 12 speed has the exact same ratios as the 6 speed in direct but, of course they can be split. I did the math using my rear gear with the available radios in the 12 speed and I would benefit greatly by the added RPM choices at highway speeds. SO, I guess I will have to swap out the 6 speed for a 12 but would have preferred to stay with twin sticks if possible. Quote Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540120 Share on other sites More sharing options...
880joe Posted October 12, 2023 Share Posted October 12, 2023 Yes they made 2 stick 12 speeds 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540121 Share on other sites More sharing options...
doubleclutchinweasel Posted October 12, 2023 Share Posted October 12, 2023 Well there you go! Learn something new on here every day! Thanks, 'Joe! Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540122 Share on other sites More sharing options...
doubleclutchinweasel Posted October 12, 2023 Share Posted October 12, 2023 Actually, it looks like it also had an air shift portion on it. So, are you looking for a 12-speed with ONLY 2 sticks, or a 12-speed that ALSO has 2 sticks? LOL! Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540123 Share on other sites More sharing options...
Licensed to kill Posted October 12, 2023 Author Share Posted October 12, 2023 (edited) 23 minutes ago, doubleclutchinweasel said: Actually, it looks like it also had an air shift portion on it. So, are you looking for a 12-speed with ONLY 2 sticks, or a 12-speed that ALSO has 2 sticks? LOL! That is the shifting diagram that I found online as well and took the left diagram to suggest that they DO come in a twin stick but then looked at that diagram and went, "WTF, where is reverse???". That left me wondering what that diagram even means. UPDATE, so in an effort to find the gear ratios for the TRTXL 107 (direct) I found that the diagram on the left shows the deep reduction on a second stick while, as I now understand it the 1070 (OD) trans had the deep reduction on the dash (air) so both versions used air splitter on the stick. Edited October 12, 2023 by Licensed to kill 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540124 Share on other sites More sharing options...
fjh Posted October 12, 2023 Share Posted October 12, 2023 14 minutes ago, Licensed to kill said: That is the shifting diagram that I found online as well and took the left diagram to suggest that they DO come in a twin stick but then looked at that diagram and went, "WTF, where is reverse???". That left me wondering what that diagram even means. Reverse is on the air switch! Low low can be operated only in 1st gear! un less its been modified other wise! Quote Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540125 Share on other sites More sharing options...
doubleclutchinweasel Posted October 12, 2023 Share Posted October 12, 2023 So, again... Are you looking for something with NO air at all? Or were just just wondering about the shift pattern? Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540126 Share on other sites More sharing options...
doubleclutchinweasel Posted October 12, 2023 Share Posted October 12, 2023 Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540127 Share on other sites More sharing options...
doubleclutchinweasel Posted October 12, 2023 Share Posted October 12, 2023 Maybe you need this... Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540128 Share on other sites More sharing options...
doubleclutchinweasel Posted October 12, 2023 Share Posted October 12, 2023 Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540129 Share on other sites More sharing options...
67RModel Posted October 12, 2023 Share Posted October 12, 2023 I thought the all Mack 12 speeds were air shifted for the 10 road gears. The difference being with the compound low could be air shifted with a switch on the dash or a second stick on the floor. Someone else might know better.... Quote Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540132 Share on other sites More sharing options...
doubleclutchinweasel Posted October 12, 2023 Share Posted October 12, 2023 (edited) 3 minutes ago, 67RModel said: I thought the all Mack 12 speeds were air shifted for the 10 road gears. The difference being with the compound low could be air shifted with a switch on the dash or a second stick on the floor. Someone else might know better.... From what I have researched in the past few minutes, I think you are 100% right. The difference seems to be in how the deep reduction is operated (air or stick). I'm just not sure what LTK was wanting to know. Maybe I read too much into his question! Edited October 12, 2023 by doubleclutchinweasel Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540133 Share on other sites More sharing options...
67RModel Posted October 12, 2023 Share Posted October 12, 2023 Just continue with the plan of running an E6-350 and get a duplex or triplex. Plenty of gears and they should bolt together. Don't lug it and you should be fine. For hobby bobtailing or light loads I would think you would not have any problems. I had a B81 that was repowered with a 237 maxidyne and it still had the 18 speed quad box. It was completely fine for just driving around in...... Quote Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540135 Share on other sites More sharing options...
doubleclutchinweasel Posted October 12, 2023 Share Posted October 12, 2023 2 minutes ago, 67RModel said: Just continue with the plan of running an E6-350 and get a duplex or triplex. Plenty of gears and they should bolt together. Don't lug it and you should be fine. For hobby bobtailing or light loads I would think you would not have any problems. I had a B81 that was repowered with a 237 maxidyne and it still had the 18 speed quad box. It was completely fine for just driving around in...... Agree completely. For a hobby truck, any of the Du- Tri- Quadru-plex boxes would be fine, even behind the 350. But, at the same time, a 5- or 6-speed would probably be fine for a bobtail ride, too. There is still plenty of torque in that 350 to drag it around, even without keeping the RPMs in the sweet spot. Bobtailing my R600 with the 250 Thermodyne and the 15-speed RoadRanger, I usually only used 4th, 6th, 8th, and 10th. It's be different if you had 80,000# behind it. Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540136 Share on other sites More sharing options...
Licensed to kill Posted October 12, 2023 Author Share Posted October 12, 2023 1 hour ago, doubleclutchinweasel said: So, again... Are you looking for something with NO air at all? Or were just just wondering about the shift pattern? I was wondering if they made one with no air shift at all. It appears not but that is OK was just wondering. Quote Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540137 Share on other sites More sharing options...
Licensed to kill Posted October 12, 2023 Author Share Posted October 12, 2023 15 minutes ago, 67RModel said: Just continue with the plan of running an E6-350 and get a duplex or triplex. Plenty of gears and they should bolt together. Don't lug it and you should be fine. For hobby bobtailing or light loads I would think you would not have any problems. I had a B81 that was repowered with a 237 maxidyne and it still had the 18 speed quad box. It was completely fine for just driving around in...... I considered that. I have a tri-plex but don't think it is any good and I have a duplex that might be good. For what I am doing I don't think it would be a problem even behind the 350 but have already changed everything over to accept the newer type trans (assuming "HOPING" that the 12 speed is a direct drop in from the TRXL1070 6 speed). Then again, if I went back to the 2-3-4plex, I should be able to go back to the factory B-61 trans mounts/clutch linkage etc. Just investigating my options. Don't expect to pull more than maybe 25,000 pounds MAX but more likely <20,000 pounds or even <12,000 ponds. Don't want to go to all this effort then be limited to what I MAY want to do with it down the road. Quote Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540138 Share on other sites More sharing options...
doubleclutchinweasel Posted October 12, 2023 Share Posted October 12, 2023 Or find you another Maxidyne to go with that 6-speed. I've seen your work, so there isn't much of a limitation on what you can shoe-horn in there! Comes down to cost and availability. Can't wait to see how it all works out. Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540139 Share on other sites More sharing options...
67RModel Posted October 12, 2023 Share Posted October 12, 2023 The thing about the 12 speeds is they are somewhat scarce and when you do find one they are rather spendy.....at least around here. Quote Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540143 Share on other sites More sharing options...
doubleclutchinweasel Posted October 12, 2023 Share Posted October 12, 2023 6 minutes ago, 67RModel said: The thing about the 12 speeds is they are somewhat scarce and when you do find one they are rather spendy.....at least around here. I do hear a lot of folks say they really like them. Tends to make them scarce and expensive. Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540144 Share on other sites More sharing options...
terry Posted October 12, 2023 Share Posted October 12, 2023 I had an overdrive 12 spd in a DM dump with 4.17 rears, had the engine where I could turn 2300 RPM if I wanted, it could bury the 80 MPH speedometer! Terry Quote Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540147 Share on other sites More sharing options...
Licensed to kill Posted October 12, 2023 Author Share Posted October 12, 2023 (edited) If I had gone with the triplex would have save a PILE of work/problems but was warned about their durability with anything like what I am running for an engine. I would have to change out the clutch but don't know about the flywheel. At this point a 12 would be a nicer choice if I can get one at no cost, otherwise will seriously consider a triplex, Maybe take the one I have apart to see of it is/can be made any good. Have my doubts as it was missing the side plate and was full of mouse nest. . Already have WAY too much money in this to be buying another trans. The guy I got this motor/trans from might have a 12 and MIGHT trade me straight across (maybe not) but have not been able to get ahold of him yet. He might also have a good triplex but I know he has scraped them in the past so may not have one. Edited October 12, 2023 by Licensed to kill Quote Link to comment https://www.bigmacktrucks.com/topic/73413-mack-12-speed/#findComment-540148 Share on other sites More sharing options...
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