Lost Reverse, 68 Newport still fighting me.

WOT440

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Like the title says. I took my Newport for a cruze this morning. Put on around thirty miles or so. Stopped to take a few pictures. Rolled past the spot I intended to park, when shifted to reverse to back it up a bit .... nothing. Still had forward luckily, so I drove it home. Checked the fluid and checked for leaks. No leaks and the fluid level is exactly where it should be. This is a rebuilt 727 from Advance Auto with less than 500 miles on it. Unfortunately, it was purchased by the PO around ten years ago, so no warranty for me. Any help would be greatly appreciated.

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Now, after cooling down a bit, it will go into reverse and moves, but it slips. Could it need a band adjustment?
Possible it wasn't set up correctly when it was rebuilt? I have no experience working on transmissions other than changing fluid and filters.
 
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Now, after cooling down a bit, it will go into reverse and move, but it slips. Could it need a band adjustment?
I have no experience working on transmissions other than changing fluid and filters.
That eliminates the broken band theory.
 
The low-reverse band is used in R but also in 1 (not breakaway in D). So if the band is broken or out of adjustment you must notice this also in 1. Another problem is a too low line pressure, in R the line pressure is 2.5 more than in forward. So if ther's a problem in the front pump (or regulator valve) you'll feel it first in R.
 
Anyone know if there is enough room to make the rear band adjustment with a 1/4 in torque wrench, or will I need to purchase the adaptor. FSM gives both options. TIA. I'm sure there are some additional underlying issues with this trans as it still doesn't downshift properly. Low governor valve pressure. I have a feeling this trans was never set up properly when it was rebuilt. This one may need a tech with a little more troubleshooting experience than I have to get it sorted out. This morning with cold fluid, it moved in reverse, but still weak.


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Low/reverse band is adjusted from inside. You have to remove the pan. Good news is after the pan is off it is easy to get to.
I always just adjust the bands till just tight enough to stop the driveshaft from turning (adjustment done in neutral), then back off the adjuster 3/4-1 turn tighten lock nut and done. Also turning effort will be noticably harder in reverse direction this is normal.
 
Low/reverse band is adjusted from inside. You have to remove the pan. Good news is after the pan is off it is easy to get to.
I always just adjust the bands till just tight enough to stop the driveshaft from turning (adjustment done in neutral), then back off the adjuster 3/4-1 turn tighten lock nut and done. Also turning effort will be noticably harder in reverse direction this is normal.
Hmmm, that's an interesting method.....never heard of that before. Did you ever check back to see what that torque value was?
 
I use always a small torque wrench (w/o adaptor) and i tighten at 72 inch-pounds as said in the manual. It's always the same value since the first Torqueflite in 1956 !!! Then 3 turns back, not 2, but i've checked on the first manual i found, a '66 manual .
I use a torque wrench because 20 years ago i found a Facom torque wrench for low tightening torques (72 inch-pounds = 0.8 kgm).

[edit] 3 turns back on Plymouth 66 FSM but 2 turns back on 67 and 69 Chrysler/Imperial FSM
 
Before you get too deep check your linkages and kickdown adjustments.
It looks like you have a service manual to follow the procedure. Improper linkage adjustments could be part of the issue or causing excessive wear requiring the band adjustments that are being talked about.
 
Before you get too deep check your linkages and kick-down adjustments.
It looks like you have a service manual to follow the procedure. Improper linkage adjustments could be part of the issue or causing excessive wear requiring the band adjustments that are being talked about.
Thanks for this suggestion. Linkage seems fine. Shifter works as it should. Nothing is loose. Shift indicator is lined up and I adjusted the kick down per the manual. Also seems to be working properly. One thing I noticed, the trans kicked down at around 3/4 throttle. Open to any suggestions.
 
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Hmmm, that's an interesting method.....never heard of that before. Did you ever check back to see what that torque value was?
I never did. It does not take much torque to stop the drum (not as tight as the fsm 72 inch pounds). That is why I only back it off ~1 turn. The factory settings are always 72 inch pounds then back it off a certain number of turns usually 2-3 by halves or quarters. While this is doable in a larger car with single exhaust. A 727 in a, A body with dual exhaust you can hardly see the kickdown adjuster. Then when you remove the cluster of adapters to arrive at 72 inch pounds, you have to unwind from that torque settings, that's a lot going on, laying on your back for most of you. The tighten with a open end wrench and then back off a turn or so is much easier. You want enough clearance for oil to get in there when disengaged and not so much that the servo is travelling the whole cylinder to engage.
Like I say low reverse band will not improve shifts 1-2, 2-3, that is in the kickdown.
This has been explained in Mopar Action a couple of times which is I'm sure where I got it from.
I basically did this from when I was a dumb kid, and did not have the tools to do it per fsm. From that time frame also learned about not enough clearance in low reverse will stop you like a brake on 1-2 shift and after a couple of tries it breaks the band. More learning.
 
Like the title says. I took my Newport for a cruze this morning. Put on around thirty miles or so. Stopped to take a few pictures. Rolled past the spot I intended to park, when shifted to reverse to back it up a bit .... nothing. Still had forward luckily, so I drove it home. Checked the fluid and checked for leaks. No leaks and the fluid level is exactly where it should be. This is a rebuilt 727 from Advance Auto with less than 500 miles on it. Unfortunately, it was purchased by the PO around ten years ago, so no warranty for me. Any help would be greatly appreciated.

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Your first/reverse band probably broke. it's in the far rear inside the trans and it needs to come out...disassembled.
 
So this doesn't answer the question but is instead a new question. A few decades ago I had a 1967 New Yorker. I put a different radiator in it. After I did that, it wouldn't move. It took me a while for the light bulb to go on and realize it was low on fluid. I put fluid in and then the transmission worked fine forever after... Except that shifting from drive to 2 or 1 resulted in less than crisp shifter action. The transmission went between gears fine, but moving the actual lever didn't. I've been wondering about that for three decades. Why could it have responded as such?
 
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