Help Support Ram Forum by donating:


  1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Transmission issues after gear ratio swap

Discussion in 'Heavy Duty' started by loveracing1988, Feb 14, 2021.

  1. U&A

    U&A Senior Member

    Posts:
    8,725
    Likes Received:
    16,897
    Joined:
    Apr 29, 2016
    Location:
    Michigan
    Ram Year:
    2016 3500 SRW
    Engine:
    6.4 HEMI
    At a minimum you need to make sure your gears and tire size are programmed into the truck.

    That alone will affect the difference between the output shaft speed and the wheel speed.

    If they are different it will possibly/eventually cause a problem.

    The way I understand it is a gear change should not confuse the transmission IF you did reprogram for this. tire size included




    Sent from my iPhone using Tapatalk
     
    Last edited: Feb 14, 2021
    AFMoulton likes this.
  2. U&A

    U&A Senior Member

    Posts:
    8,725
    Likes Received:
    16,897
    Joined:
    Apr 29, 2016
    Location:
    Michigan
    Ram Year:
    2016 3500 SRW
    Engine:
    6.4 HEMI
    Not 100% true.

    They are supposed to relate the output shaft speed to the sensors at the wheels.


    Sent from my iPhone using Tapatalk
     
    AFMoulton likes this.
  3. U&A

    U&A Senior Member

    Posts:
    8,725
    Likes Received:
    16,897
    Joined:
    Apr 29, 2016
    Location:
    Michigan
    Ram Year:
    2016 3500 SRW
    Engine:
    6.4 HEMI
    No issues at all.


    O.P.
    6th is not a towing gear anyway. Run in 4th or 5th on the highway and keep the RPM up. Hemi’s power curve showes it NEEDS to run up there close to 3,000if you want power of any kind.

    I run 60-70 and in 5th when towing with my 4.88’s. Puts me between 2,700 and 3,500 If i need more i go down to 3rd

    Let her scream


    Sent from my iPhone using Tapatalk
     
    AFMoulton likes this.
  4. chris1126

    chris1126 Senior Member

    Age:
    41
    Posts:
    372
    Likes Received:
    301
    Joined:
    May 8, 2020
    Location:
    pa
    Ram Year:
    2017
    Engine:
    6.4
    i changed my gears and tires and only reprogrammed for tires. havent had any issues myself. are you using tow/haul?
     
  5. loveracing1988

    loveracing1988 Senior Member

    Posts:
    3,485
    Likes Received:
    901
    Joined:
    Jul 4, 2013
    Location:
    Clarkston, MI
    Ram Year:
    2014
    Engine:
    6.4
    Fully loaded it is only 2000 or so pounds. Like I said it isn't weight it is wind that is the problem with this trailer. I would tow my 10k 5th wheel at 65 in 5th gear provided I was on flat ground and that was with the 3.73 gears, not I'm up about 400 rpms from that.
    To the others yes I programed the gear ratio with alfaobd and set the tire sizes with my trinity.
     
  6. loveracing1988

    loveracing1988 Senior Member

    Posts:
    3,485
    Likes Received:
    901
    Joined:
    Jul 4, 2013
    Location:
    Clarkston, MI
    Ram Year:
    2014
    Engine:
    6.4
    Tow haul didn't do anything
     
  7. yoda

    yoda Senior Member

    Age:
    51
    Posts:
    429
    Likes Received:
    226
    Joined:
    Jul 25, 2016
    Ram Year:
    2015
    Engine:
    6.4 Hemi
    You need to fix your input/turbine speed sensor code first. I dont think your gear swap or tires has anything to do with this fault.
    A flaky input speed sensor signal can cause gear ratio faults and will cause shifting issues.
    The input/turbine speed rpm should read about the same as engine rpm in park.
     
    mtofell and U&A like this.
  8. loveracing1988

    loveracing1988 Senior Member

    Posts:
    3,485
    Likes Received:
    901
    Joined:
    Jul 4, 2013
    Location:
    Clarkston, MI
    Ram Year:
    2014
    Engine:
    6.4
    Turns out the overdrive clutch was on its way out the door. So I now own a 2020 3500 with a cummins and most importantly not the 68rfe. Pretty sad that I only got 75k out of the transmission in my 2500.
     
    G. Mcpherson and AFMoulton like this.
  9. U&A

    U&A Senior Member

    Posts:
    8,725
    Likes Received:
    16,897
    Joined:
    Apr 29, 2016
    Location:
    Michigan
    Ram Year:
    2016 3500 SRW
    Engine:
    6.4 HEMI
    Congratulations on the new truck! Hope it all goes well and trouble free.


    Sent from my iPhone using Tapatalk
     
    wyo2track, G. Mcpherson and AFMoulton like this.
  10. 6.4LMegaMan

    6.4LMegaMan Senior Member

    Posts:
    172
    Likes Received:
    158
    Joined:
    Mar 13, 2017
    Ram Year:
    2016
    Engine:
    6.4L
    Yikes. Sorry to hear your troubles. My valve body went out at 75k. On the bright side you now have a beast of a truck. Sucks you had to get it this way but don't look back and enjoy it.

    Sent from my SM-N975U using Tapatalk
     

Share This Page