TH400 how much fluid?

[Ed]

Hi guys,

I think I may have over filled the TH400, as it is dropping fluid.

how much fluid does one of these take?

Chers

Ed

[ACE]

Hi Ed,
Did you check the Dipstick???
10.4 litres dry (including converter)
 3.7 litres  (service)
Regards ACE  8)

[Ed]

yep checked the dipstick but dont really trust it.

10L dry, hmm I only put 4L in.

was reading somewhere that to check fluid level the engine should be running?

Is this the case?

Cheers

Ed

[ACE]

Yep, the engine should be running so that the pump fills the converter etc ???
ACE  8)

[Ed]

Thanks ACE,

I've never owned an auto before.

If I get the transmission serviced while in the car, is it a simple matter of dropping the pan out only, as opposed to removal of the entire transmission??

I am reluctant to remove my transmission if I can help it.

Cheers

Ed

[FC-V8]

Ed
 Â       To service the box they just remove the pan, no need to remove the box unless there is a problem. I think you can also put a shift kit in while the pan is off as well.
 Â     Did you put in new front & rear seal while you had the box out ? As they tend dry out after sitting around a while.
Glenn

[Ed]

Hey Glenn,

shise.. no front seal, it looked in good condition lol *fingers crossed*
the rear can be done easy enough i guess.

hope it's not leaking..

Tony had shift kitted it before hand I know, I just need to fix up some small annoying leaks.

I'm probably going to get somebody else to do this job... I'm exhausted by it.

Cheers

Ed

[FC-V8]

Ed
    Another place they leak is where the dip stick tube inserts into the box. They need a good rubber oring & plenty of sealant. I know what you mean you get to the stage where you have had enough & just want it finished.
Glenn

[Ed]

Glenn,

I made sure the dipstick hole wouldnt leak by using lots of sealant etc. and a new o-ring.

put some chrome on the car last nite.. getting there slowly.

Cheers

Ed

[Ed]

After getting under the car,

Im pretty sure it's only the pan gasket which is leaking.

I couldnt find a drain hole to drain the fluid from the trans???

Is this a case of pulling out the slip yoke and letting it all run out?

Not real keen on spilling fluid all over the carpeted garage floor  ;D

Cheers

Ed

[FE_225]

Ed
No drain plugs on a TH400. Take out the modulator on the drivers side of the box and you can drain off the excess thru there. The pan still remains full of fluid tho. If you loosen all the pan bolts, you can raise one end of the pan and drain off a bit more fluid that way.
Cheers
Tony

[FC-V8]

Ed
          When you do get the pan off you can buy a aftermarket chrome pan that has a bolt for draining, so you don't have to go through the same drama next time you take the pan off
Glenn

[Ed]

Thanks for the tip Tony, what were they thinking when they desgined the TH400 pan?

Hi Glenn,

good idea.. pan plug!
I'm a little skint at this stage of the build, so I may get a wrecked sump and cut the plug out and weld it in.

Anybody have an old sump lying about with a good plug??

Cheers

Ed

[FC-V8]

Ed
         That the idea, just be careful & measure the clearance between the pan & the valve body but I can't see why it won't work.
Glenn

[FE_225]

Apparantly the original pans did have a drian plug. The problem was, mechanics would pull the plug to drain the fluid and not bother changing the filter. After many g/box failures under warranty due to the filter not being changed, GM did away with the drain plug so mechanics would have to drop the pan to drain it.
Cheers
Tony

[Ed]

ahh.. so that's what they were thinking.

I may still put a plug in since warranty period is over. :)


Cheers

Ed

[RET]

Apparantly the original pans did have a drian plug. The problem was, mechanics would pull the plug to drain the fluid and not bother changing the filter. After many g/box failures under warranty due to the filter not being changed, GM did away with the drain plug so mechanics would have to drop the pan to drain it.
Cheers
Tony

Well, I've learnt something new today.  Thanks Tony.  Does fly in the face somewhat of the old GM-H aphorism: "Cure the cause, not the effect", doesn't it? ::)

cheers
RET

[FC-225]

Thanks for the tip Tony, what were they thinking when they desgined the TH400 pan?

Hi Glenn,

good idea.. pan plug!
I'm a little skint at this stage of the build, so I may get a wrecked sump and cut the plug out and weld it in.

Anybody have an old sump lying about with a good plug??

Cheers

Ed

All the GM autos had drain plugs at one stage,(except maybe the THM 350) and were all deleted over a period of time on cost cutting exercises. As a matter of fact I think the Trimatic one was deleted due to an employee 'suggestion scheme'.
I certainly remember cursing them when we had to drain and service them at the proving ground !!!

Cheers

AL