Hi,

I have a 1984 Trans Am with a TH 700R4.
I have never repaired/rebuilt a transmission.

I have some questions:

1.
Do I have to remove the tranny if I want to replace the seal at the front?
I think it is necessary, is this correct?

2.
I can move the driveshaft up/down left/right in the tranny about 0.5mm.
I think it is too much. Is something worn? Usually what? Bearing?
And could this affect the leaking? I mean that it moves too much and ruins
the seal? I think I should fix this problem first and then put the new
seal in. Am I right?

3.
The car is standing. I accelerate and at about 5mph speed I hear a short and not
loud burring noise let's say for a second. What could this be? Maybe because
the driveshaft is loose in the tranny?

4.
What does "endplay" mean in case of a transmission?

Thank you,

Laszlo

 

Sounds wore out man.

 

Thank you.

What is worn out?
Is there a bearing inside that I should replace?

Laszlo

 

1) Unfortunately, removal of the trans is nescessary to replace the front pump seal
2) It is somewhat normal for the driveshaft to move up and down a bit. There is a bushing in the tailshaft of the trans that can be replaced if you think it may be worn. If you change it, you will need a new rear seal as well. In the states, $15 in parts.
3) The noise you describe is not typical noise for an auto trans. The fact that it quickly goes away makes me think it could be the universal joints in the driveshaft.
4) Endplay in the trans is internal space. It allows the "guts" of the trans room to grow as it warms and expands. .015-.040 is rtypical input shaft end play. It is measures when the converter is removed, off the tip of the input shaft.

 

Hi,

Thank you very much for helping!

1.
a, If the tranny is leaking at the front (top) then is this a wrong pump seal?
b, Do I need any special tool for the replacing the pump seal?

2.
How much can the driveshaft move up and down?
I think it is about 0.5mm. How can I make sure that it is OK?
I do not trust the dealer here.
(That is why I try to make everything myself what I can...)

3.
How can I test the universal joints of the driveshaft?
And if they are wrong what should I do? Should I replace something?
Usually what can be worn in them?

4.
If I just replace the pump seal, do I have to adjust the endplay?
And if it is too big how can I correct it?

Thank you,

Laszlo

 

Laszlo,
Glad to help, That is what the site is here for
Here is what I would do:
When you say leaking at the top, I presume you mean from the upper part of the bellhousing area. There is also a vent on the very top of the exterior of the trans. I presume you are not talking about that.
The front pump seal is not special. It is very common to alot of gm cars and transmissions. They are easy to remove. Carefully pry it out. To replace, you can carefull tap it in using a drift or a block of wood.
U-joints are a safety issue. I would remove the driveshaft after carefully blocking the car so it will not roll away. Then place the driveshaft on the bench and wiggle the yoke and joints to feel for excessive play. Also, pull some of the u-joint caps off. If dry and rusty, replace both u-joints.
With the driveshaft out, wiggle the output shaft of the trans. More than 1/4 inch (.250 ) would somewhat concern me. With the driveshaft out, you can look in the tailhousing at the condition of the rear bushing. They have dimples in the wear surface to help with a visual inspection. If you are fortunate enough to have a new bushing available, you can compare the 2 for a good assessment.
Endplay adjustment is internal and is controlled by a selective thickness shim under a bearing. You cannot change endplay without beaking down the trans. Pump seal is a remove and replace job. Be sure to inspect the pump bushing when the seal is out, and reinstall the seal retainer.

 

Hi,

I did not know about that vent.
Where is it exactly?
Can the tranny leak there at the ventil?
Could this be the problem?
And in this case what can be wrong there at the vent?
The vent itself or something else?
How can I check whether it is the pump seal or the
vent?

What I see now is that if I remove the black cover of the
torque converter then the front of the transmission is wet
there.

Thank you,

Laszlo

 

The leak you see is likely the front pump seal. There are also 7 bolts that cold the pump on that could leak, but they usually do not.
The vent is on the outside top of the case and is aimed toward the pass side. When the trans is overfilled or overheated, it can puke fluid out and it will run down the pass side center of the case.
You will want to carefully inspect the pump bushing when the seal is removed. If it is worn, the converter will wobble slightly, preventing the seal from doing its job. 1/2 the time a seal leaks, the bushing is the root of the problem. Other times it is just a worn out seal.

 

Thank you.

What you told me here (worn bushing) was my thought regarding
the rear seal. That something inside (bushing, bearing) is worn and
the seal can not really work.

My idea:
I will buy both rear and front bushings and replace them.
I want to replace them without inspection.
I want to make sure that they are OK.
Is this easy? Do I need special tools or knowledge?

Laszlo

 

Hi,

I received now the repair manual.
I see that there are the following bushings:
- front pump bushing
- front stator bushing
- rear stator bushing
- rear case bushing
- extention housing bushing

Is it easy to replace them?
I mean can I just take them out or do they stuck?

There is an output shaft sleeve with an O ring.
Is this the same as the extention housing bushing
or what is it?

Thank you,

Laszlo

 

Laszlo,
There are 12 bushings in a 700r4/4l60 trans. There are only 2 that are servicable without completely disassembling the transmission. Those 2 are the front pump and rear extension housing bushings.
To properly change the front pump bushing, the pump must be removed from the trans, unbolted and split in half, then the busing can be driven out with the proper bushing driver and a hammer.
The extension housing bushing is easier. Simply remove the housing, take it to the bench and tap the new bushing in (again with the proper driver). This is after knocking out the old bushing.

In summary, bushing replacement is not easy. It requires proper tools and experience to set them in the proper location (depth). If you have doubts, let a pro do them.
Bushings are solids sleeves of metal, o-rings are rubber.

 

Thank you! I will think about replacing the bushings...

Can you please tell me what is the TCC wire?
What is TCC for?

Laszlo

 

The tcc harness plugs into the drivers side of the trans. It is the wiring that feeds the lock up curcuit. Lock up converters eliminate all internal slippage when locked up. This usually happens in 3rd or 4th gear. Lock up reduces heat in the trans and give a couple extra miles per gallon in fuel savings.

 

Thank you! What is this lock up? Are talking about the torque converter?
And what gives the signal through the wire to the transmission? Can I test
is somehow if it works?

Laszlo

 

Have a look here.
http://www.c4guru.com/modules.php?na...iewtopic&t=425

 

Hi,

Which one is the right transmission fluid for my TH 700R4?
It is an 1984 Trans Am. I saw somewhere that Dexron II
is the right one. Is this true? Where can I buy it? Here in
the shops I see only Dexron III. What is the difference?

Thank you,

Laszlo

 

dexron III is the replacement for dexron II. We don't sell dexron II no more.

 

Hi,

Could anybody tell me how much ATF I need if I change it?
I mean that not all of the fluid comes out, we can not change
the whole amount. How much comes out of this transmission?
In litres please if it is possible.

Thank you,

Laszlo

 

Hi,

Does anybody know what is the option MD8?

Thank you,

Laszlo

 

When you drop the pan to change the filter and/or transmission fluid, the amount of fluid required would be about 5 quarts. At .946 litres per quart, you would need 4.73 litres. To remove all the fluid, you would also have to remove the transmission and torque converter. The torque converter holds another liter of fluid which can only be drained if the torque converter is removed from the vehicle. Generally, it is not necessary to be concerned with the fluid left in the torque converter when doing the routine maintenance of fluid replacement.

The MD8 option means an automatic transmission is installed.