Anyone know anything about the TH125?
#1
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Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Anyone know anything about the TH125?
My friend's 84 Omega is fine when its cool, but after running for several minutes (maybe 30) it stalls whenever its stopped and in gear. He says it behaves as though its a manual and you forget to use the clutch. I dont know if it has a TH125 or a TH125C, so I dont know if it has a TCC or not. Is this a common problem, does anyone know what it might be?
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Car: 84 Z28
Engine: 355 (fastburn heads, LT4 HOT cam)
Transmission: 700R4
Axle/Gears: 9-bolt, 3.27
I have dealt with far more TCC solenoids than I have all other problems with 125's. In fact, I rarely ever see any other problem with a 125.
I'm 98% sure it is the TCC solenoid.
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I'm 98% sure it is the TCC solenoid.
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Working on:
'84 Z28 LG4 305 with 208,000 original miles!
Dual electric fans (from a formula).
145 MPH IROC Speedo
430 HP 350 (ZZ430) Coming soon! (Building it myself, so I don't get those AWESOME valve covers!)
Starting to look like the Kicker poster child!
ASE Certified Master Tech
+ L1 Advanced Engine Performance
+ X1 Undercar Specialist
And....A sig. that's getting way too long!
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Car: Take
Engine: Your
Transmission: Pick
I also agree. While you have the side cover off, replace the gear switches because they like to set codes.
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#5
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Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Can I get at it without dropping the transaxle? As long as we're on the subject, is this a common problem with 440T4's as well?
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Yes you can get it off in the car. You will have to take the side cover off as that is where the Valve Body is located. It is held in place with a Torx bolt.
This is not a common problem on 440-T4's. They have a whole grocery list of their own problems!
This is not a common problem on 440-T4's. They have a whole grocery list of their own problems!
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Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
I don't mean these exact symptoms, but TCC solenoid problems in general. I have another car with a 440T4 that shudders badly trying to make a 4-3 downshift, but seems to behave itself on a 4-2 downshift.
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CHeck this first: Take the vacuum hose off at the modulator while the engine is running and see what happens. It should either speed up, run rough or stall. If nothing happens or hardly anything then the vaccum line (probably right inside the manifold) is carboned up, restricting vacuum flow. THis in turn doesn't allow pressure to rise quickly in response to engine load changes. This is a very common cause of failure on the 440-T4. If this is the problem, take a small drill bit and by hand, clean out the passage. It is also possible that the 3rds are slipping or even the 2nds (they take the most pounding as from seconed gear on, they are the drive clutch). ALso add 2 quarts of oil, even if it is to the full mark hot. These trannies desperately need more oil for both lube and cooling problems, but also to keep the filter covered during different manuevers. If the oil is dark and stinky it is likely that the tranny is gone.
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Car: 86 Z28
Engine: 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
<font face="Verdana, Arial" size="2">Originally posted by transfixleo:
ALso add 2 quarts of oil, even if it is to the full mark hot. These trannies desperately need more oil for both lube and cooling problems, but also to keep the filter covered during different manuevers. If the oil is dark and stinky it is likely that the tranny is gone. </font>
ALso add 2 quarts of oil, even if it is to the full mark hot. These trannies desperately need more oil for both lube and cooling problems, but also to keep the filter covered during different manuevers. If the oil is dark and stinky it is likely that the tranny is gone. </font>
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That all depends on the tranny. THIS tranny NEEDS it. A 400 usually wants a little LESS than full. Many of your O/D FWD trannies seem to need this too, by the way.
#11
Re: Anyone know anything about the TH125?
good day to all
new in the forum
have a problem with daewoo racer 97 with gearbox th125c , 3 gears,
goes up to 60 ktms speed and then gearbox neutralizes , does not go to third gear, replaced fluid bt no positive result , any suggestion to check before remove the gearbox fm the car?
tks in advance
new in the forum
have a problem with daewoo racer 97 with gearbox th125c , 3 gears,
goes up to 60 ktms speed and then gearbox neutralizes , does not go to third gear, replaced fluid bt no positive result , any suggestion to check before remove the gearbox fm the car?
tks in advance
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