TH400 trans fluid capacity

Ninety-Eight · Post by **Ninety-Eight** » Mon Sep 01, 2008 8:58 am

Hi

I have a TH400 trans here which is rebuilt and needs to be fully filled (inc torque converter)

Can anyone confirm the capacity for ATF for this box and converter.

its a 1965 model if that makes a difference?

Magnetteman · Post by **Magnetteman** » Mon Sep 01, 2008 11:21 am

IIRC the fill level on the TH400 is at the same level as the modulator on the side of the 'box.
I'm not sure of the capacity but removing the modulator and filling until it dribbles out should get the level, remembering to refit the modulator before running it up to fill the convertor.

Hopefully that helps a little, if not please feel free to disregard.

Ninety-Eight · Post by **Ninety-Eight** » Mon Sep 01, 2008 11:48 am

thanks, thats a decent start. Filling autoboxes up from dry is a PITA, especially when the only way to check the level "properly" is with the motor running...

Eliot · Post by **Eliot** » Mon Sep 01, 2008 6:36 pm

is there no mark on the dipstick?
on the th350 and th700r4, its usually at least as high as the pan rail.

Ninety-Eight · Post by **Ninety-Eight** » Tue Sep 02, 2008 7:52 am

yes, the dipstick is marked but thats no use unless the car is idling in neutral. The trans is rebuilt and has been sat for a while dry, so I need to fill the trans and leave it for 24-48 hours for the seals to soak and expand before I can run it.

So I need to know how much to put down the tube...

kiwicar · Post by **kiwicar** » Fri Sep 05, 2008 6:26 pm

how about
1 Fill it up until it comes out the hole you are filling it through
2 leave it for 48 hours
3 drain it through the drain hole
4 put the plug back in the bottom
5 put half the oil you just drained out back in
6 Run it and top it up as you go using the dipstick as a guide.
or have I missed something?
Mike

Eliot · Post by **Eliot** » Fri Sep 05, 2008 6:36 pm

kiwicar wrote:how about
1 Fill it up until it comes out the hole you are filling it through
Mike

Urr no - you fill GM transmissions up through the dipstick tube - which is several feet long - so I dont reccomend you try that.

To the O/P fill it up to the highest level on the dipstick and leave it overnight. Doubt it will go down much.
When you get it started, try to put it in drive - it will barely (if at-all) move.
Top it right up again.
Then run through all the gears (just going up and down your drive, a few feet)
check oil again
go for a short drive
check oil again
you're done.

kiwicar · Post by **kiwicar** » Sat Sep 06, 2008 10:18 am

OK I was missing something

Mike