Goin' to band camp! An easy band adjustment tutorial

Transmissions and Rear Ends

  1. NoCar340

    NoCar340 Well-Known Member

    Messages:
    1,240
    Likes Received:
    176
    Joined:
    Dec 7, 2013
    Location:
    Upper MI
    Put that flute down, you weirdo! :D

    There's more to servicing your automatic transmission than just the occasional fluid and filter change. Chrysler bands should be checked and adjusted occasionally, and if you don't know when the last time it was done, then it should be done the next time you're under the car. In the case of the front (kickdown) band, you don't even have to get (very) dirty or drop the pan. It's external! More than likely, the front band is the one that will be further out of adjustment anyhow, and it's the one that affects shift quality.

    It's a simple procedure, far from some kind of automatic-transmission voodoo or common core mathematics. All you need is two open-end wrenches, one 5/16" and one 3/4". I use a 5/16" 8-point socket rather than a wrench, because the adjuster itself is 4-sided rather than a hex, and it's just easier to get the 8-point on with the ratchet handle in a useful position. If you want to use a socket you might already have, the square adjuster can also be turned with an 11/32" 12-point. Nope, you probably don't have that either. :D

    Please read the whole thing, and closely. I'm responsible for neither broken parts from torque specs being misread, nor the fact that you (or your wife/husband/carpool/dog) hate the jump from reverse to drive after adjusting the rear band hot-rod style, nor the fact that you just got done adjusting them and then realized there was a second approach.

    The front band adjustment is the same for all the "modern" TorqueFlites, be they A5xx, A727 or A9xx, lockup or non, 3x/4x RH or RE, regardless of block size, cylinder count, etc.
    The adjuster is on the driver's side, just forward of the shift/throttle-pressure linkage connections, and a little higher up, on the side of the case (see picture). It points toward the driver's rocker at a slight upward angle. It's a 3/4" hex locknut with the 5/16" square-head threaded adjuster in the center of it. Put the 5/16" wrench on the adjuster, then use the 3/4" wrench to loosen the locknut enough that you can move the adjuster freely with your fingers. It doesn't have to go far (quarter turn, maybe a half). Holding the locknut loose--don't let it move with the adjuster!--thread the adjuster into the transmission until it's finger tight. Using your small wrench tighten it until you feel solid resistance; just snug it well. If you want to go all service manual, the spec is 72lb/in. Snug with the wrench works perfectly. Now, continuing to hold the locknut in place, back the adjuster out 2.5 turns. Hold the adjuster in that position while you tighten the large locknut. Spec on the locknut is 35lb/ft; you're using a pretty-good size wrench so getting it to that torque isn't much past snug. Just make sure it's tight, and you're good.

    AT1.gif

    The rear band adjustment is the same procedure for all transmission variants, but with a different clearance specification between A727 and A9xx transmissions. That sounds technical, but it just means a different number of back-off turns on the adjuster. ;)
    The rear band adjuster is inside the pan, so you'll have to drain the fluid. You might as well have a new filter and fluid on hand, since it's somewhat hidden behind the filter anyhow. You're this far in... replace the filter!
    Once you've got the filter out of the way, the locknut/adjuster should be obvious since it's lookin' right at you but now pointing at the passenger's side and at a downward angle (see picture, which is of a 727). The adjustment procedure is the same as the front band including the 72lb/in or "wrenched snug" measurement--it'll be obvious back here, because you'll be able to see that you've removed all the slack from the band at the same time the resistance becomes evident. For the A727 the number of back-off turns is the same (2). In the case of the A9xx transmissions, it's 4 turns. Again, make sure the adjuster stays in position while you tighten the locknut!

    AT2.gif

    Install the new filter, replace the pan, and fill with Mopar Type 2 (Dexron II/III) fluid. As is always the case, fluid level must be checked with the car on level ground and the gear selector in neutral. But you already knew that. ;)

    The above are the factory method for band adjustments. Like a little more oomph in your shifts, along with less wear?

    Front band: Instead of 72lb/in or wrench-snug, tighten the adjuster finger tight, approximately 10lb/in, then back it off 1.5 turns.
    Rear band: Use the 10lb/in or "finger tight" torque spec. The number of back-off turns is unchanged in either case. You really won't see a difference in shifting here, but you will get a little more "lurch" when shifting from park/neutral to drive or reverse as the band will grab more aggressively. If that doesn't sound appealing, by all means skip it! Other than a minor increase in rear band life there's no need to make this particular change. You can do the front-band change only if you prefer. They don't affect each other and the front band is where the party happens.
    Substitute Ford Type F or FA fluid in place of Mopar Type II or Dexron II/III fluid.

    You will notice an increase in shift firmness, but the above changes will not turn your automatic into a neck-snapping, tire-wasting screech-bang transmission by any stretch of the imagination. If that interests you, we can talk about the accumulator and line pressure. :cool:

    You should be able to make these adjustments in about 1/3 the time it took me to write it.

    To my knowledge, all of the above applies to any Mopar automatic with hydraulically-actuated band engagement, including late stuff like the A500 (40RH/42RH or RE/44RE) and A518 (46RH/RE). However, at no point should anything but Mopar ATF+4 be used in an electric-solenoid-controlled (RE) transmission!
     
  2. Roadrunner360

    Roadrunner360 Well-Known Member

    Messages:
    161
    Likes Received:
    25
    Joined:
    Mar 26, 2011
    Location:
    Indiana
    Thanks for sharing ! Good Info!
     
    NoCar340 likes this.
  3. kkritsilas

    kkritsilas Well-Known Member

    Messages:
    1,811
    Likes Received:
    347
    Joined:
    Jun 21, 2012
    Location:
    Calgary, Alberta, Canada
    Shouldn't this be a stickie in the transmission/drivetrain section?
     
    NoCar340 likes this.
  4. Aspen500

    Aspen500 Well-Known Member

    Messages:
    4,808
    Likes Received:
    1415
    Joined:
    Feb 14, 2015
    Location:
    Rib Mountain (Wausau) WI
    This one time,,,,,at band camp,,,,,,,,,I adjusted my bands. lol
    Yes, very good info!
    Wrong forum but Ford tranny's had band adjustment intervals also.
     
    NoCar340 likes this.
  5. NoCar340

    NoCar340 Well-Known Member

    Messages:
    1,240
    Likes Received:
    176
    Joined:
    Dec 7, 2013
    Location:
    Upper MI
    Yeah, I figured I could have a little fun with the title and most everyone would get it... :D
     
  6. Captain Caravelle

    Captain Caravelle Moderator--Mopar Maniac

    Messages:
    10,789
    Likes Received:
    1121
    Joined:
    Jan 29, 2012
    Location:
    Hogtown, Ontario
    A
    Great idea.
    It is now.
     
    NoCar340 likes this.
  7. Intrepolicious

    Intrepolicious Well-Known Member

    Messages:
    206
    Likes Received:
    17
    Joined:
    Feb 16, 2017
    Location:
    Florida
    What was the substitution bit for? I'm confused.
     
  8. 80mirada

    80mirada Well-Known Member

    Messages:
    1,116
    Likes Received:
    312
    Joined:
    Sep 3, 2012
    Location:
    Wisconsin, West Bend depends
    Type F has a higher boil point, and it's friction modifiers improve shift firmness
     
    Camtron and Intrepolicious like this.
  9. Elwood P Dowd

    Elwood P Dowd Active Member

    Messages:
    33
    Likes Received:
    3
    Joined:
    Sep 20, 2019
    Location:
    London, OH
    Good Lord, for as easy as it seems to adjust your front or kickdown band that thing sure is awkward to get to.
     
    BudW likes this.
  10. Aspen500

    Aspen500 Well-Known Member

    Messages:
    4,808
    Likes Received:
    1415
    Joined:
    Feb 14, 2015
    Location:
    Rib Mountain (Wausau) WI
    Isn't it though?:confused: Awkward is another term for darn near impossible.
     
  11. volare 77

    volare 77 Well-Known Member

    Messages:
    1,271
    Likes Received:
    166
    Joined:
    Jun 12, 2014
    Location:
    maryland
    Thanks for posting.
     
  12. Camtron

    Camtron Well-Known Member

    Messages:
    461
    Likes Received:
    162
    Joined:
    Apr 25, 2019
    Location:
    Chicago
    Well, I know what I’m doing this weekend. Great write up, very informative.