Randy mckinney Posted July 23, 2014 Share Posted July 23, 2014 85 mack 12 spd no forward gears shifts ir rev fine but when you shift from netrual to low nothing you can hear air but no clunk like i hear when i shifts to rev any pointers would be great Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/ Share on other sites More sharing options...
gearhead204 Posted July 23, 2014 Share Posted July 23, 2014 randy is the air coming out of the trans case or out of the shift handle exhaust line? Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-253777 Share on other sites More sharing options...
Randy mckinney Posted July 23, 2014 Author Share Posted July 23, 2014 Air is coming from exhaust line. It kinda seams like the shift cylinder is frozen up this truck has a "dirty air" problem so i keep filter changed prety often. Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-253779 Share on other sites More sharing options...
Brian Blaylock Posted July 23, 2014 Share Posted July 23, 2014 Mine done that once it had a broken air line on the back of the transmission Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-253791 Share on other sites More sharing options...
Randy mckinney Posted July 23, 2014 Author Share Posted July 23, 2014 I have found the problem. I removed air cylinders from tranny the rev. side moves free the low and high one does not move at all. Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-253803 Share on other sites More sharing options...
Dave G Posted March 8, 2022 Share Posted March 8, 2022 My 06 Mac vision with a maxi torque 10 speed trans Does not want to stay in high range. We'll shift into high range but when you let off the accelerator it tries to shift itself back into low range and grinds. Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491274 Share on other sites More sharing options...
doubleclutchinweasel Posted March 9, 2022 Share Posted March 9, 2022 2 hours ago, Dave G said: My 06 Mac vision with a maxi torque 10 speed trans Does not want to stay in high range. We'll shift into high range but when you let off the accelerator it tries to shift itself back into low range and grinds. Synchro or air cylinder? Maybe? Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491306 Share on other sites More sharing options...
Onyx610 Posted March 9, 2022 Share Posted March 9, 2022 6 minutes ago, doubleclutchinweasel said: Synchro or air cylinder? Maybe? I was thinking synchro ring also Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491311 Share on other sites More sharing options...
mechohaulic Posted March 9, 2022 Share Posted March 9, 2022 6 minutes ago, doubleclutchinweasel said: Synchro or air cylinder? Maybe? not familiar with an '06, as a thought; if it were a bad synchro would there not be a grinding rough shift. air cyl having a crack on plunger ? which side gets more air- low or high to make a shift? Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491312 Share on other sites More sharing options...
Joey Mack Posted March 9, 2022 Share Posted March 9, 2022 if it doesnt do it in 5th,, highly likely its in the back box. synchro sliding clutch may have diamond shaped teeth by now.. Just for kicks, is the grinding strong in the shifter? I ask because many guys use the gear shifter as an arm rest, which can mess the shift fork up.. good luck Jojo Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491313 Share on other sites More sharing options...
Onyx610 Posted March 9, 2022 Share Posted March 9, 2022 Also check air regulator/valves on it Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491314 Share on other sites More sharing options...
mechohaulic Posted March 9, 2022 Share Posted March 9, 2022 ideas are based on the R/ R trans. have seen the plunger nut back off not allowing a complete syncro shift. post was 3hrs ago; Dave G still around, could answer some questions such as + does the shift grind== is there an air leak in either range etc Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491316 Share on other sites More sharing options...
fjh Posted March 9, 2022 Share Posted March 9, 2022 1 hour ago, mechohaulic said: ideas are based on the R/ R trans. have seen the plunger nut back off not allowing a complete syncro shift. post was 3hrs ago; Dave G still around, could answer some questions such as + does the shift grind== is there an air leak in either range etc Guys ! 12 speed!!!! (1070)? You likely have a broken shift rail ! The trans ! The other thing that commonly happens is the snap ring in the split cylinder breaks ! Lift the lid off and look down inside there is a tapered shift rail it is likely broken! Just saying! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491340 Share on other sites More sharing options...
Onyx610 Posted March 9, 2022 Share Posted March 9, 2022 2 minutes ago, fjh said: Guys ! 12 speed!!!! (1070)? You likely have a broken shift rail ! The trans ! The other thing that commonly happens is the snap ring in the split cylinder breaks ! Lift the lid off and look down inside there is a tapered shift rail it is likely broken! Just saying! I’m gonna go with this Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491341 Share on other sites More sharing options...
Joey Mack Posted March 9, 2022 Share Posted March 9, 2022 I thought the truck was an '06 CX ? Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491342 Share on other sites More sharing options...
mechohaulic Posted March 9, 2022 Share Posted March 9, 2022 original post with a 12 speed is from 2014 this post is 7 yrs later and states a 10 speed 1 Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491343 Share on other sites More sharing options...
doubleclutchinweasel Posted March 9, 2022 Share Posted March 9, 2022 I was assuming we were talking to the guy (Dave G) in the new post with the 10-speed. Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491374 Share on other sites More sharing options...
fjh Posted March 9, 2022 Share Posted March 9, 2022 I'm going to have to pay more attention to the dates of the posts I guess! I'd like to know how these old posts keep getting recycled! It had zero replies when I looked at it first! just getting old and senile I guess!😐 1 1 Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491380 Share on other sites More sharing options...
Joey Mack Posted March 9, 2022 Share Posted March 9, 2022 (edited) too me,,,, its easy to miss it, especially when I 'scroll' quickly... so what do you think the issue is? jojo Edited March 9, 2022 by Joey Mack I type poorly Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491381 Share on other sites More sharing options...
doubleclutchinweasel Posted March 9, 2022 Share Posted March 9, 2022 33 minutes ago, fjh said: I'm going to have to pay more attention to the dates of the posts I guess! I'd like to know how these old posts keep getting recycled! It had zero replies when I looked at it first! just getting old and senile I guess!😐 I figure somebody is looking through the old posts for a similar problem, hopefully with a solution attached. And, if they don't find one, maybe they tag onto a post that is close and hope for an answer? Might be better to just start a new thread for the exact problem. Might catch more attention, and hopefully cause less confusion. Anyway, I'm bettin' one of you guys can help the man out! Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491387 Share on other sites More sharing options...
fjh Posted March 9, 2022 Share Posted March 9, 2022 (edited) 46 minutes ago, Joey Mack said: too me,,,, its easy to miss it, especially when I 'scroll' quickly... so what do you think the issue is? jojo As stated ! Shift rail! pricey to impossible fix parts are scarce! PAI MABE! Fuller time! Edited March 9, 2022 by fjh Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491391 Share on other sites More sharing options...
Joey Mack Posted March 9, 2022 Share Posted March 9, 2022 PAI, is still making these parts.. The shop I use locally, rebuilds tranny's and rear's with PAI parts.. I think Eaton parts are still available as well.. But I know that the Mack's are built with PAI.. I have had 4 done in the last year. jojo Quote Link to comment https://www.bigmacktrucks.com/topic/36440-maxi-torque-problems/#findComment-491394 Share on other sites More sharing options...
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