Zeuz Posted January 12, 2022 Share Posted January 12, 2022 I have a 2016 pinnacle with a MDrive automatic.on the highway the transmission slips out of gear then back into gear within a second..does it every once in awhile..sometimes I will go days and won't do it...has anyone had this issue before ? Thanks Quote Link to comment Share on other sites More sharing options...
70mackMB Posted January 12, 2022 Share Posted January 12, 2022 I'm NO expert here but, the 2014/15 Volvo with an I(idiot)Drive l drive did the same thing. They thought it was the clutch and replaced it the first time in the shop but didn't stop the problem. As I was told there is a modular valve of some kind on the side of the transmission. It was replaced the second visit to the shop due to contaminated air supply. Have not had a problem since. .....Hippy 1 1 Quote Link to comment Share on other sites More sharing options...
Popular Post Joey Mack Posted January 12, 2022 Popular Post Share Posted January 12, 2022 Yes... clean/filterd air is a must!!! and NO air brake alcohol in the system to displace water. the shift cover can't handle it... BTW..... I call "I-Shift" "I-Don't Shift" What pisses me off about all of these automated system's... Is the FACT that People who buy these P.O.'S truck's, are the R+D ( research and developement) for the products.... OK, time to go..... jojo 1 1 1 Quote Link to comment Share on other sites More sharing options...
Zeuz Posted January 13, 2022 Author Share Posted January 13, 2022 35 minutes ago, 70mackMB said: I'm NO expert here but, the 2014/15 Volvo with an I(idiot)Drive l drive did the same thing. They thought it was the clutch and replaced it the first time in the shop but didn't stop the problem. As I was told there is a modular valve of some kind on the side of the transmission. It was replaced the second visit to the shop due to contaminated air supply. Have not had a problem since. .....Hippy Quote Link to comment Share on other sites More sharing options...
Zeuz Posted January 13, 2022 Author Share Posted January 13, 2022 I'm going to check it ..I know sometimes it won't go in gear when ur stoped or rev up .I took the negative off the batteries and it was fine but still does it ..and the slipping in and out of gear I definate will check for that module thanks Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted January 13, 2022 Share Posted January 13, 2022 I forgot to add, that there is a small air tank under the driver's,,,, I mean 'sitter's' seat, that is for the tranny...you may need to clean it out.. jojo 1 Quote Link to comment Share on other sites More sharing options...
Zeuz Posted January 13, 2022 Author Share Posted January 13, 2022 I seen that tank under the driver's side I'm going to also double check the lines and clean it...thanks 1 Quote Link to comment Share on other sites More sharing options...
Vmac3 Posted January 13, 2022 Share Posted January 13, 2022 It may also be the clutch actuator that is acting up. I hope you have warranty on this transmission. More failures to come. V 1 Quote Link to comment Share on other sites More sharing options...
Zeuz Posted January 14, 2022 Author Share Posted January 14, 2022 12 hours ago, Vmac3 said: It may also be the clutch actuator that is acting up. I hope you have warranty on this transmission. More failures to come. V I hope it ain't much of a issue ..I'm waiting for the truck to get back from the road..and I sure ain't got no warranty ..the driver said it hasn't done it all day ..thanks Quote Link to comment Share on other sites More sharing options...
upsman Posted January 14, 2022 Share Posted January 14, 2022 Thought the Mdrives had a 750k warranty Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted January 14, 2022 Share Posted January 14, 2022 M-drives don't make it to 750... they are junk... 1 Quote Link to comment Share on other sites More sharing options...
upsman Posted January 15, 2022 Share Posted January 15, 2022 18 hours ago, Joey Mack said: M-drives don't make it to 750... they are junk... Thanks. Mines at 651…. Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted January 15, 2022 Share Posted January 15, 2022 Yeah, I'm sorry if I'm harsh.. I just think about owner operators who need to get the most out of thier trucks and this tranny/clutch, has many issues.. I have pulled many of them before 300,000 miles.. you are doing good if it's the original tranny and clutch.. jojo 1 Quote Link to comment Share on other sites More sharing options...
Zeuz Posted January 25, 2022 Author Share Posted January 25, 2022 Well since I last posted about my issue with the MDrive slipping in and out of gear .I still can't find anyone here in south Florida who works on them..the Mack dealer will buy the DEF is deleted..it still does the same thing I been having it on the road every day..it sometimes takes long to shift and now when u press the brakes it won't go into neutral it stays in drive unless u press like hell..hope Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted January 25, 2022 Share Posted January 25, 2022 shut off the 'grade gripper 'feature and try it again.... jojo 1 Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted January 25, 2022 Share Posted January 25, 2022 since it's deleted,,, well.... who know's.. you playing with fire by having it deleted... jojo Quote Link to comment Share on other sites More sharing options...
Zeuz Posted January 25, 2022 Author Share Posted January 25, 2022 2 hours ago, Joey Mack said: since it's deleted,,, well.... who know's.. you playing with fire by having it deleted... jojo I know I bought it deleted....the truck had a strap get stuck around the drive shaft on highway and locked the wheels on highway when I bought it..it snatched all the wires and every airline hose from the carriage bearing on back to tail lights ..I replaced everything..but when it was replaced the grade gripper came up on the dash then it disappeared after awhile..the only thing I noticed they did was the put a airline hose from the wet tank to the other tank which I seen other mack's don't have..so both tanks fill up at the same time....also there's a air valve on the side of the first rear axle on driver's side that has the grade gripper valve ..there's a air line hose missing on that valve ..the truck runs and everything works ..but they couldn't figure out what airline hose went there...do you think that could be the problem? Quote Link to comment Share on other sites More sharing options...
fjh Posted January 31, 2022 Share Posted January 31, 2022 (edited) On 1/15/2022 at 5:43 AM, Joey Mack said: Yeah, I'm sorry if I'm harsh.. I just think about owner operators who need to get the most out of thier trucks and this tranny/clutch, has many issues.. I have pulled many of them before 300,000 miles.. you are doing good if it's the original tranny and clutch.. jojo Totaly agree jojo ! However the way these are programed to fail the clutch early ! If your not watching these will start out in 4th gear every time ! Slipping the clutch for the first 20 feet before totally engaging! If ALL the trucks were programed to start out in 2nd there would be half the clutch wear! getting them past that magical 750 mark MAYBE how ever clutch wear is not a warrantable item so its beneficial to mack/ volvo to to program this way so why change it! A 8-10 thousand dollar clutch job is beneficial to them ! At 250000 - 300000!😡 Edited January 31, 2022 by fjh 1 Quote Link to comment Share on other sites More sharing options...
upsman Posted February 2, 2022 Share Posted February 2, 2022 If I’m bobtailing it wants to start in 4th but if I momentarily hold the trailer knob in it will drop to 2nd then. Quote Link to comment Share on other sites More sharing options...
fjh Posted February 2, 2022 Share Posted February 2, 2022 (edited) 1 hour ago, upsman said: If I’m bobtailing it wants to start in 4th but if I momentarily hold the trailer knob in it will drop to 2nd then. Yup why does it start out in 4th? cause they programed it like that! It can be programed to start in 2nd but they don't! Once the truck is rolling empty or loaded the trans ecu can take a full gear or half gear what ever is needed! Slipping the clutch is not necessary but they do it! This has pissed me off since they started pushing this trany down our throats ! Why not make the trans do its job! Thats why its there! Edited February 2, 2022 by fjh 1 Quote Link to comment Share on other sites More sharing options...
67RModel Posted February 2, 2022 Share Posted February 2, 2022 4 hours ago, fjh said: Yup why does it start out in 4th? cause they programed it like that! Most likely so it would save a an extra thimble full of fuel every week and so they could say it gets up to 3% better fuel economy than the previous iteration. I have driven these and the Detroit DT12 transmission and from a drivability standpoint they really are less than desirable. Yes they make going down the road a little "easier" since you don't physically have to go up and down through the gears but once you get into any type of tight quarters that requires a lot of slow speed backing or maneuvering they absolutely suck. I've had several instances where getting a 53' trailer into a super congested terminal that was designed for 32' trailers the air actuated clutch was working so much the low air alarm came on. I personally have no use for these Volvo I shift (I mean Mack M drive) transmissions. Plus you guys say they have poor longevity.....Its amazing to me what people will give up for convenience. 1 Quote Link to comment Share on other sites More sharing options...
Zeuz Posted February 3, 2022 Author Share Posted February 3, 2022 5 hours ago, 67RModel said: Most likely so it would save a an extra thimble full of fuel every week and so they could say it gets up to 3% better fuel economy than the previous iteration. I have driven these and the Detroit DT12 transmission and from a drivability standpoint they really are less than desirable. Yes they make going down the road a little "easier" since you don't physically have to go up and down through the gears but once you get into any type of tight quarters that requires a lot of slow speed backing or maneuvering they absolutely suck. I've had several instances where getting a 53' trailer into a super congested terminal that was designed for 32' trailers the air actuated clutch was working so much the low air alarm came on. I personally have no use for these Volvo I shift (I mean Mack M drive) transmissions. Plus you guys say they have poor longevity.....Its amazing to me what people will give up for convenience. My MDrive still doing the same slipping in and out on highway cruising..it does it a little more with 90,000 or more..it's still going ..but I'm taking it in to Mack next week..I talked to them of course they said it can be anything.. Quote Link to comment Share on other sites More sharing options...
JoeH Posted February 3, 2022 Share Posted February 3, 2022 There is one thing it CANT be: Cheap! 1 Quote Link to comment Share on other sites More sharing options...
67RModel Posted February 3, 2022 Share Posted February 3, 2022 11 hours ago, Zeuz said: My MDrive still doing the same slipping in and out on highway cruising..it does it a little more with 90,000 or more..it's still going ..but I'm taking it in to Mack next week..I talked to them of course they said it can be anything.. I know a lead mechanic at a mostly Mack fleet runnning a lot of MDrives and a lot of the failures they were seeing were from from one of the wiring harnesses (I think on the left side of the unit) were getting corroded somehow and causing all sorts of weird symptoms. This was several years back now but I know they had they exact same thing happen on a few of their trucks. It could possibly be a technical service bulletin by now. These are rebadged Volvo I Shift transmissions with different software programming to match the programming and characteristics of the Mack MP engines. Maybe check some of the Volvo forums (if they have one) to see if there is any information there? Quote Link to comment Share on other sites More sharing options...
upsman Posted February 3, 2022 Share Posted February 3, 2022 My Mdrive backs up way easier and smoother than the dt12’s I’ve driven and the Eaton ultrashifts are an utter nightmare to drive. Quote Link to comment Share on other sites More sharing options...
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