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Guy
Dodge Dakota
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12/01/2011
21:45:35
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 Subject: Auto tranny not shfting
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My 1993 v6 3.9L Dakota with an automatic transmission won't shift from 3rd to 4th gear. For a long time this was a sporadic problem for about the last three years, but it has now become all the time. The tranny shifts from 1st thru 3rd no problem but that's where it goes bad because it won't go into 4th at all. When I'm driving at 65 MPH the engine is taching at about 2900 RPMs when it should be around 2000.
Also when I punch the gas hard the shifting from 2nd to 3rd acts funny for awhile. The engine tachs up too high and then slams into gear.
I only have 128,000 miles on it and the transmission was rebuilt at 103,000. I have been going through a lot of motor oil as well while this has been happening. Is there a relation? Does this transmission operate by vacuum and if so do I have an intake vacuum leak? What else could it be?
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Bob Lincoln
Dodge Dakota
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12/02/2011
08:31:52
| RE: Auto tranny not shfting
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Several things going on here. First, the oil consumption:
Check inside the throttle body to see if it's wet and oily at the bottom of the plenum. There is often a "belly" gasket leak here at the intake which can suck oil into the manifold. A vacuum leak can also throw off the MAP sensor readings and change the air/fuel mixture.
As to the shifting, there are a few suspects. Since you report unusual shifting behavior from 2-3 after hitting the throttle, it's possible that that, and the failure to shift to 4th, is caused by the "TV" (throttle valve, or downshift) cable being stuck or even detached from the throttle body. There is a ball/socket connection from cable to throttle body that can break, and there is also an adjustment there. There should be about 1/16" to 1/8" slack in the cable when opening the throttle, before the TV cable begins to move.
Another possibility is that the overdrive solenoid has a loose or intermittent connector (at the left rear of the transmission, 3-prong plug). Or the solenoid pack can vibrate loose from the throttle body, causing the fluid to bypass the solenoid and prevent the 3-4 shift. The latter is solved by dropping the pan and tightening 3 torx screws on the right side of the valve body, that hold the solenoid pack on.
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Bob Lincoln
Dodge Dakota
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12/02/2011
08:33:04
| RE: Auto tranny not shfting
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To answer your question, the transmission is not shifted by vacuum; but by hydraulics, and for the 3-4 shift and lockup, by electronics.
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Guy
Dodge Dakota
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12/02/2011
16:08:33
| RE: Auto tranny not shfting
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Thanks for your response. I checked on the throttle valve cable. While the clip is connected there is about 1/16 of play until the cable moves like you said. When I disconnect the ball/socket clip from the throttle assembly I find about 3/4 of an inch of free play where the clip just slides on the cable until there is any resistance at all. Is that to be expected?
So that I understand you the solenoid pack is on the throttle body or is it up inside the pan of the transmission?
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Bob Lincoln
Dodge Dakota
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12/05/2011
08:40:38
| RE: Auto tranny not shfting
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You test the play with the cable connected, so it sounds good. Have someone watch the transmission end and see that the lever it's connected to on the side of the case moves without binding, when you open the throttle.
The solenoid pack is inside the transmission, screwed to the right side of the valve body. So you have to drain the fluid to get at it. Check the electrical plug and wires first. In my case, the screws vibrated loose and I could wiggle the solenoid pack.
One other thing I should mention is that a bad thermostat (stuck open), or bad/intermittent connection from the 2-wire temperature sensor, or failed sensor, can cause it to fail to shift to 4th. It's very unlikely, but worth checking, since there's no disassembly required. The computer does not activate the OD solenoid until the coolant temperature is at least 60F, and lockup not until 140F. That's based on the temp sensor at the thermostat (later Dakotas have a sensor in one of the transmission cooler lines). But if your temp gauge reads normal, you should be OK on this. Normally it shifts into 4th once the gauge needle touches the cold line.
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Guy
Dodge Dakota
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12/05/2011
08:49:03
| RE: Auto tranny not shfting
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Thanks for your help. I'll get someone to help me soon and I'll
be in touch either way .
Guy
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Guy
Dodge Dakota
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12/14/2011
07:17:10
| RE: Auto tranny not shfting
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Hey Bob,
You nailed it. The linkage on the transmission where the TVC connects was hanging up. All is well now. What a relief. Thanks again.
Guy
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jay
Dodge Dakota
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11/19/2012
19:13:43
|  RE: Auto tranny not shfting
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Message:
Was driving my 1993 dodge dakota and lost all gears except
for park and reverse. I bought the truck knowing it probally
needs a valve body,he said it may be frozen is that true.
Would it be easier when doing the valve body to do the
solenoids at the same time. The truck has about 158000
miles on it.
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Penny
Dodge Dakota
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11/12/2015
16:40:10
| RE: Auto tranny not shfting
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Message:
I have a 93 with a 3.9 ever since I bought it
ive had a shifting problem. It will drive fine
in 1st then shift to second but thats it. I can
get up to freeway speeds but at 60-65mph its
doing about 3 grand on the tach. With the motor
reeving for long trips I dont want to crack the
block or throw a rod... Ive checked the VSS
Sensor on the side of the tranny and it
wiggles. Also my gear shift indicator is way
off. I wont hit drive till the indicator is way
down on D1.. Any help Would be Appreciated
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dreamboy0000
Dodge Dakota
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11/12/2015
17:10:05
|  RE: Auto tranny not shfting
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It wiggles...
Didn't maintain it huh! Thought the truck would cheat death!
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Penny
Dodge Dakota
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11/13/2015
16:19:09
| RE: Auto tranny not shfting
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Message:
What I meant by Wiggles is it feels like the whole
unit is lose but the bolt holding it on is tight.
Has a worn out feel to it but I dont want to drop
$70 bucks to replace it and that not be the
problem since autozone wont take sensors back.Your
comment helped tremendously....
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billyandanne
Dodge Dakota
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3/13/2016
06:56:17
| RE: Auto tranny not shfting
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Message:
My 2000 dakota 3.9 4x4 lost fluid from the 2
cooling lines that rubbed on the harmonic balancer
and cut the lines. I fixed the 2 lines and refilled
the fluid and now the transmission won't shift into
a higher gear than 1st gear. Could the fluid that
sprayed out when the lines were cut , have gotten
on a sensor or wires somewhere underneath and be
causing this?
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