1. Join the Community!

    DSMtuners is a massive archive of DSM information - but more importantly, it's a COMMUNITY! Join in and participate with other DSMers, and invite all of your DSM friends to make this place their home. Chat with others, create a build thread, post questions and answers. Get involved! Logging in will also remove many of the advertisements, along with this notice. ;)

1G Running a AWD as Front wheel only

Posted by j_norton, Jul 19, 2019

Please Support ExtremePSI
Please Support Fuel Injector Clinic
  1. j_norton

    j_norton Probationary Member

    26
    5
    Joined Nov 27, 2010
    Norwich, Connecticut
    Now they tell me that I need work done on the drive-shaft (propeller). They say it needs to be repaired or replaced. Meanwhile I need to use the car for only local commute. If they pull out the drive-shaft can I still use the car as front-wheel? The transmission should not care that it is not driving a shaft and the differential should not care that it is driven by the wheels and not by the shaft, as in coasting. Will the computer detect this condition?

    I appreciate your insight on this thought.
     

    243  0

    1990 Eagle Talon TSi
    · 1G DSM
    Loading...
  2. Canadian_CD9A

    Canadian_CD9A Proven Member

    431
    116
    Joined Feb 10, 2012
    Winnipeg, MB, Canada
    No, the car spins the axle with least resistance, so your transfer case would be spinning away, but you would be going nowhere until the VCU heats up enough to lock. It's a good way to burn out your VCU. You would need a VCE to make it work.
     
  3. OH91awd

    OH91awd Proven Member

    522
    219
    Joined Sep 22, 2011
    chillicothe, Ohio
    is this the same place that told you that your rear subframe was toast?
     

    Drag Race Build 2K  16

    1992 Eagle Talon TSi AWD
    10.89 @ 125.67 · 1G DSM
    Loading...
  4. ThunderChild

    ThunderChild Supporting VIP

    2,413
    638
    Joined Jan 5, 2012
    Rathdrum, Idaho
    Correct, viscous coupler eliminator or a welded diff is needed.
    @j_norton If you need a vce, lmk I have one in my trans not being used cuz I have a welded diff too, just left it in when I did the diff.
     

    Street Build 90  3

    1990 Plymouth Laser N/T
    fwd · manual · 1G DSM

    226  8

    1987 Toyota Pickup/Hilux
    awd · manual · Misc Vehicles

    Street Build 737  7

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM

    Street Build 936  1

    1992 Eagle Talon TSi AWD
    manual · 1G DSM

    Street Build 2K  10

    1992 Eagle Talon TSi AWD
    awd · manual · 1G DSM
    Loading...
  5. j_norton

    j_norton Probationary Member

    26
    5
    Joined Nov 27, 2010
    Norwich, Connecticut
    Thanks for the info. I did not know what a VCU and VCE was but I searched this site that found that driving just the front wheels on a AWD is discussed here and requires installation of a Viscous Coupler Eliminator. I, probably can no longer get a VCE, and even if I could, I would not find anyone locally to install it. Having local competent mechanics around here is the biggest problem of keeping this car alive. I will continue to look for ways to repair the car as a AWD . I will post my specific issue in a separate post. Thank you all, again.
     

    243  0

    1990 Eagle Talon TSi
    · 1G DSM
    Loading...
  6. ThunderChild

    ThunderChild Supporting VIP

    2,413
    638
    Joined Jan 5, 2012
    Rathdrum, Idaho
    Installing a viscous coupler eliminator is pretty easy, you just take the fifth gear cover off the transmission, remove the VCU snap ring, then remove the VCU itself (there's a detent ball to keep track of and out back in it's little hole) and then slide the VCU on, then reinstall the snap ring and cover.

    Like I said, I have one I don't need, so if you wanna go that route lmk.
     

    Street Build 90  3

    1990 Plymouth Laser N/T
    fwd · manual · 1G DSM

    226  8

    1987 Toyota Pickup/Hilux
    awd · manual · Misc Vehicles

    Street Build 737  7

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM

    Street Build 936  1

    1992 Eagle Talon TSi AWD
    manual · 1G DSM

    Street Build 2K  10

    1992 Eagle Talon TSi AWD
    awd · manual · 1G DSM
    Loading...
    j_norton likes this.
  7. j_norton

    j_norton Probationary Member

    26
    5
    Joined Nov 27, 2010
    Norwich, Connecticut
    @ ThunderChild, thanks for the offer but please give me a couple of weeks to attempt to solve my issues with the AWD. The VCE may be my option if my attempts fail.
    Based on @Canadian_CD9A post, I surmise that the VCU in the transaxle distributes the drive torque between the front and back wheels. With the VCE in place, will all the torque go to the front wheels or half front and half back?
     

    243  0

    1990 Eagle Talon TSi
    · 1G DSM
    Loading...
  8. Canadian_CD9A

    Canadian_CD9A Proven Member

    431
    116
    Joined Feb 10, 2012
    Winnipeg, MB, Canada
    The VCU is just a locking mechanism, located outside of the open center differential. It locks with friction when there is enough speed difference between the front and rear.
    With the VCE, the front and rear axles get locked together, so torque distribution percentage doesn't really matter. It's going to suck to drive, but it will keep you moving temporarily.
     
    ThunderChild likes this.
  9. ThunderChild

    ThunderChild Supporting VIP

    2,413
    638
    Joined Jan 5, 2012
    Rathdrum, Idaho
    As @Canadian_CD9A said, with the vce, it's a 100% lock between all 4 wheels, so full time locked 4wd. It's a little less comfy to drive, but not bad in my mind. For fwd you won't even be able to tell, I drove mine in fwd mode for about 6 months while getting other things done, and with the vce in there was zero issue, since at that point the front diff is still acting normally to distribute the tq evenly to each front wheel.
    Once you ad in 2 more wheels (AWD style) at the back and they don't roll at the same rate as the fronts, it likes to bind on tight turns or if your tires are different diameters/worn unevenly.
     

    Street Build 90  3

    1990 Plymouth Laser N/T
    fwd · manual · 1G DSM

    226  8

    1987 Toyota Pickup/Hilux
    awd · manual · Misc Vehicles

    Street Build 737  7

    1997 Mitsubishi Eclipse Spyder GST
    fwd · manual · 2G DSM

    Street Build 936  1

    1992 Eagle Talon TSi AWD
    manual · 1G DSM

    Street Build 2K  10

    1992 Eagle Talon TSi AWD
    awd · manual · 1G DSM
    Loading...
  10. j_norton

    j_norton Probationary Member

    26
    5
    Joined Nov 27, 2010
    Norwich, Connecticut
    I get it now but I was thinking of using the VCE and removing the driveshaft so the diff is not driven. Does that get you a normal front wheel drive, or will the diff complain being free-wheeling?
     

    243  0

    1990 Eagle Talon TSi
    · 1G DSM
    Loading...
  11. techboy

    techboy Proven Member

    267
    111
    Joined Feb 3, 2018
    Lehigh Valley, Pennsylvania
    The diff is in the rear, so without the driveshaft it will be completely free wheeling. You just need install the VCE though. As stated above, it's very easy to do by taking the 5th gear cover off. I just did an output shaft swap and put a post up about it with pictures. The thread shows the process of removing the VC if you want to look at the thread. You should be able to find it as a recent under my user name.
     

    Street Build 1K  6

    1999 Mitsubishi Eclipse GST
    13.876 @ 106.97 · 2G DSM
    Loading...
  12. j_norton

    j_norton Probationary Member

    26
    5
    Joined Nov 27, 2010
    Norwich, Connecticut
    Thank you, @techboy. I read the post HOW TO: Swap AWD Transmission Output Shafts. It clearly shows how to remove the VCU. What I am not clear on is what HAS to be removed on the car to get to the 5th gear cover. Do we know for sure?
     

    243  0

    1990 Eagle Talon TSi
    · 1G DSM
    Loading...
  13. Goldenugget

    Goldenugget Probationary Member

    17
    9
    Joined Jan 30, 2019
    Albany, New York
    I just had to rebuild my drive shaft and after I added up the cost of all the parts. 3 universal's, labro boot, and 2 carrier bearings. I just got a driveshaft shop driveshaft. You still need 1 carrier bearing and 1 factory universal. If it's in the budget it's so much easier and you never have to worry about breaking it.
     

    Street Build 126  2

    1990 Mitsubishi Eclipse GSX
    awd · manual · 1G DSM
    Loading...
  14. j_norton

    j_norton Probationary Member

    26
    5
    Joined Nov 27, 2010
    Norwich, Connecticut
    @goldennugget, can you describe your new driveshaft setup? Does it use the existing front shaft with the front bearing and then a new solid shaft from there to the rear diff, eliminating the Lobro joint and the second bearing? Are you noticing any more vibrations at high speed?
     

    243  0

    1990 Eagle Talon TSi
    · 1G DSM
    Loading...
  15. Goldenugget

    Goldenugget Probationary Member

    17
    9
    Joined Jan 30, 2019
    Albany, New York
    It does the opposite of that. I have the 3.5 inch aluminum one. It replaces the first 2 sections and lobro joint and retains the factory rear section with rear carrier bearing. Zero vibrations over 100mph with solid carrier bearing bushings.
     

    Street Build 126  2

    1990 Mitsubishi Eclipse GSX
    awd · manual · 1G DSM
    Loading...
  16. j_norton

    j_norton Probationary Member

    26
    5
    Joined Nov 27, 2010
    Norwich, Connecticut
    Sounds good and easy enough to do. Thank you for sharing your experience.
     

    243  0

    1990 Eagle Talon TSi
    · 1G DSM
    Loading...

Share This Page

Support Vendors who Support the DSM Community
Archer Fabrication ECM Tuning ExtremePSI Feal Suspension Fuel Injector Clinic Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications OHM Racing RockAuto SouthBay Fuel Injectors STM Tuned VR Speed Factory WheelWell.com White Shed Speed