sodly Posted May 30, 2008 Share Posted May 30, 2008 Can someone please explain the shifting pattern in a (1993) Mack 12 speed transmission? Sorry, I don't know the number. I'm coming from a Fuller 13 speed Roadranger and I'm trying to figure out how different it is to drive a Mack 12. Thanks. Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/ Share on other sites More sharing options...
ThaddeusW Posted May 30, 2008 Share Posted May 30, 2008 Can someone please explain the shifting pattern in a (1993) Mack 12 speed transmission? Sorry, I don't know the number. I'm coming from a Fuller 13 speed Roadranger and I'm trying to figure out how different it is to drive a Mack 12. Thanks.Sodly,The 12 Speed Sort of shifts like a Super 10. you have 5 gears and you split each one from first to fifth. you can use any of the five gears in reverse. the other 2 gears come in by flipping the dash switch or second stick into low. You then use 1st in low or high split as 2 very low crawler years. Quote -Thad What America needs is less bull and more Bulldog! Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19342 Share on other sites More sharing options...
HK Trucking Posted May 30, 2008 Share Posted May 30, 2008 Can someone please explain the shifting pattern in a (1993) Mack 12 speed transmission? Sorry, I don't know the number. I'm coming from a Fuller 13 speed Roadranger and I'm trying to figure out how different it is to drive a Mack 12. Thanks.5 speeds on the stick in the standard "H" pattern, reverse is on the air shift knob, enabling the use of all 5 speeds in reverse as desired, also on the air shift knob is a hi/lo splitter which you can use to split each of the 5 gears in half, similar to operating a 2 speed rear.Depending on the vintage of your 12 speed, it may have another shift lever for the deep reduction off road lo range, or if it's a newer one (TRTXL1070B) it will have an air switch on the dashboard for the deep reduction. Quote "If You Can't Shift It Smoothly, You Shouldn't Be Driving It" Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19343 Share on other sites More sharing options...
sodly Posted May 30, 2008 Author Share Posted May 30, 2008 5 speeds on the stick in the standard "H" pattern, reverse is on the air shift knob, enabling the use of all 5 speeds in reverse as desired, also on the air shift knob is a hi/lo splitter which you can use to split each of the 5 gears in half, similar to operating a 2 speed rear.Depending on the vintage of your 12 speed, it may have another shift lever for the deep reduction off road lo range, or if it's a newer one (TRTXL1070B) it will have an air switch on the dashboard for the deep reduction.Okay... the one I was looking at had the reduction switch on the dash. But... how do you get 12 speeds outta 5 x 2? Where are the other two gears hiding? Or, how many of the 12 do you normall use in normal driving? For instance, if you're empty can you just use 5? Thanks. Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19345 Share on other sites More sharing options...
HK Trucking Posted May 30, 2008 Share Posted May 30, 2008 Okay... the one I was looking at had the reduction switch on the dash. But... how do you get 12 speeds outta 5 x 2? Where are the other two gears hiding? Or, how many of the 12 do you normall use in normal driving? For instance, if you're empty can you just use 5? Thanks.5x2 without deep reduction = 10.1st gear with either the high or low split while in deep reduction =2.Total of 12 speeds. Quote "If You Can't Shift It Smoothly, You Shouldn't Be Driving It" Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19346 Share on other sites More sharing options...
HK Trucking Posted May 30, 2008 Share Posted May 30, 2008 To answer your other questions, you can use all the combinations or whatever you need to keep the engine RPM's in the proper operating range depending on conditions.When empty you can drive it like a 5 speed if you want. Quote "If You Can't Shift It Smoothly, You Shouldn't Be Driving It" Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19347 Share on other sites More sharing options...
sodly Posted May 30, 2008 Author Share Posted May 30, 2008 So, not to sound too ignorant here... two of the gears are "deep reduction"... meaning granny low gears? Is that right? In that case you have 10 speeds for normal road operation? Thanks. Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19349 Share on other sites More sharing options...
Lmackattack Posted May 30, 2008 Share Posted May 30, 2008 you can split all 5 gears on the stick...that gives you 10 forward speeds the dash swith puts the trans in low reduction then the splitter on the gear lever can split that gear giving you 2 more speeds in "low Low"thats a total of 12 speedsIts a great trans as you have all the low gears and a good OD. Normal driving I would shift it 1-2-3-4 than split 5.. almost like a 6 speed. then in the hills you can split the gears to keep RPMs/speed up.They are getting scarce and expencive to repair! Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19350 Share on other sites More sharing options...
sodly Posted May 30, 2008 Author Share Posted May 30, 2008 Oh, I see. So first position on the shifter really handles 4 different gears (when you count all the splits... one regular split and one lo/lo-lo split). All the other positions (2,3,4,5) contain only 2 gears each. Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19351 Share on other sites More sharing options...
brutus998 Posted May 30, 2008 Share Posted May 30, 2008 Oh, I see. So first position on the shifter really handles 4 different gears (when you count all the splits... one regular split and one lo/lo-lo split). All the other positions (2,3,4,5) contain only 2 gears each.Sodly you are correct. All the way over and down is low and low-high(1st and 2nd gear). Let me tell you they are turtle slow when you have the low-range locked in!!!! Really you would want to start off in 3rd. Unless on a hill you can just keep in direct and shift like a 5 speed, then split the last one for Over-drive. Now most 12 speeds that I have seen will raise the bed with the shifter. Kick in PTO then make sure shifter is in neutral then put in gear and it will raise your bed. !st gear raises bed real slow and 3rd raises super fast. It really is a sweet tranny. You can grab 5 gears in reverse just like the old 6 speeds. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19356 Share on other sites More sharing options...
brutus998 Posted May 30, 2008 Share Posted May 30, 2008 Oh I also forgot to tell you. In the superliner that I drove w/ 12 speed it is almost impossible to grab 11th(5th direct) gear with out grinding at least a little. Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19357 Share on other sites More sharing options...
bulldog man Posted May 30, 2008 Share Posted May 30, 2008 Ya the 12spd mack tranny really does have best of both worlds in speed it is a great all around tranny it will ceep & also will run out there w/ the Kenny's & Pete's Also & To me the best part is using the stick while raising a dumpbed just like the ole 2 Stick 6 spd trannys We had a 88 RW713 Superdog w/a 450 E9 Mack coupled to a 12spd tranny 14k f/a & 44k r/a on double frame man that was 1 sweet tractor for pulling grain, lowboy, dump & log trailers with. Thats 1 of the 's i miss later yall Quote You Cant Fix Stupid. But You Can Numb It With A Sledgehammer. Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19361 Share on other sites More sharing options...
Warpman89 Posted May 31, 2008 Share Posted May 31, 2008 Oh I also forgot to tell you. In the superliner that I drove w/ 12 speed it is almost impossible to grab 11th(5th direct) gear with out grinding at least a little.my trick for that is to leave it in high and go from 4 high to 5 high, then put it in direct and rev slightly so it engages into 5 direct, it works for me and when you get the hang of it, it won't grind anymorei hope that makes sense... Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19405 Share on other sites More sharing options...
MackR797-W45Holmes Posted June 1, 2008 Share Posted June 1, 2008 my trick for that is to leave it in high and go from 4 high to 5 high, then put it in direct and rev slightly so it engages into 5 direct, it works for me and when you get the hang of it, it won't grind anymorei hope that makes sense...Yes this works for me also.Steve. Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19415 Share on other sites More sharing options...
Freightrain Posted June 2, 2008 Share Posted June 2, 2008 Kinda like a two stick, main stick up a gear, then rev it to get compound to catch up to UD. Quote Larry 1959 B61 Liv'n Large...................... Charter member of the "MACK PACK" Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19452 Share on other sites More sharing options...
Lmackattack Posted June 2, 2008 Share Posted June 2, 2008 Kinda like a two stick, main stick up a gear, then rev it to get compound to catch up to UD.larry why not just make another you tube video for us LOL!!! only if you could have charge for vewing and copying your vid LOL!!! Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19459 Share on other sites More sharing options...
Lmackattack Posted June 2, 2008 Share Posted June 2, 2008 Kinda like a two stick, main stick up a gear, then rev it to get compound to catch up to UD.larry why not just make another you tube video for us LOL!!! only if you could have charge for vewing and copying your vid LOL!!! Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19460 Share on other sites More sharing options...
Freightrain Posted June 3, 2008 Share Posted June 3, 2008 I need to get up to Stan's and get my "test drive" in his Superliner. Then videotape it.......ya, that's it.(I'll look like a tru rookie in that thing...grind'n gears like a 14 yrs with his learners permit) I'm not sure how well I could drive a "ONE" stick tranny? LOL!!!!! Quote Larry 1959 B61 Liv'n Large...................... Charter member of the "MACK PACK" Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-19489 Share on other sites More sharing options...
steveD Posted July 14, 2021 Share Posted July 14, 2021 i need the air diagram for a mack TRTXL1070B Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-476817 Share on other sites More sharing options...
John3406 Posted July 19, 2021 Share Posted July 19, 2021 They must be one tough transmission i have 2 12 speeds in RDs and all i hear is gears grinding from the idiots driving them. However i never gring a gear when i drive them. I also have a 12 speed in my superliner. The only complaint i have is all 3 of them leak oil. One leaks a gallon per week and the others are not far behind Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-477105 Share on other sites More sharing options...
theakerstwo Posted July 19, 2021 Share Posted July 19, 2021 you would be money ahead if you would spend a half of a day with them.Show them how and tell them how much its going to cost if they keep this up. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-477113 Share on other sites More sharing options...
mrsmackpaul Posted July 20, 2021 Share Posted July 20, 2021 1 hour ago, theakerstwo said: you would be money ahead if you would spend a half of a day with them.Show them how and tell them how much its going to cost if they keep this up. And fix your oil leaks would save a fortune But yes, knowing how to operate them can make all the difference and if they dont then they cant really be blamed Paul Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-477116 Share on other sites More sharing options...
terry Posted July 20, 2021 Share Posted July 20, 2021 Where are they leaking oil from? terry Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-477126 Share on other sites More sharing options...
John3406 Posted July 20, 2021 Share Posted July 20, 2021 10 hours ago, terry said: Where are they leaking oil from? terry Leaking out of the gaskets in between trans sections Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-477147 Share on other sites More sharing options...
terry Posted July 20, 2021 Share Posted July 20, 2021 1 hour ago, John3406 said: Leaking out of the gaskets in between trans sections Thats pretty unusual, have you tried tried tightening bolts that hold the cases together? terry Quote Link to comment https://www.bigmacktrucks.com/topic/3805-mack-12-speed/#findComment-477154 Share on other sites More sharing options...
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