OK to do both internal and vb dual feed on TH400? [Archive] - Chevelle Tech

: OK to do both internal and vb dual feed on TH400?


67EC
Sep 24th, 09, 12:48 PM
I have my TH400 apart. I have a Hughes forward manual only valve body, I assume it does the dual feed. Can I also remove the center lip seal from the direct drum and plug the reverse oil passage, or should I just leave it to the valve body?

THanks

jakeshoe
Sep 24th, 09, 7:54 PM
Unless they are using a seperator plate (TransGo) to do the dual feed, you must do it inside. No way to do it in the VB itself.

Skeeveman
Sep 25th, 09, 1:43 PM
I thought the manual valve body kits from most companies had you perform the internal dual feed per the instructions... or is that just on transbrake kits?

67EC
Sep 25th, 09, 1:59 PM
I thought the manual valve body kits from most companies had you perform the internal dual feed per the instructions... or is that just on transbrake kits?

I have a Hughes manual valve body and it doesnt say anything about dual feed! That is what is confusing.

Thanks for the info Jake. Is it ok to remove the one ring from the center support AND remove the center lip seal out of the direct drum?

Where is a good place to get the plug? Do auto parts store carry different sized plugs?

Skeeveman
Sep 25th, 09, 2:21 PM
Yeah, remove both and put theplug in.

I got my plug from napa, just a 3/8 cup plug. They should have it behind the counter with all their freeze plugs and whatnot. Dirt cheap.

67EC
Sep 25th, 09, 3:14 PM
Wicked, thanks!!!

jakeshoe
Sep 25th, 09, 7:32 PM
You shouldn't really need to plug it if the valve body has a dedicated seperator plate. It will be plugged at the plate.

Yes leave both seals out.

67EC
Sep 25th, 09, 9:29 PM
Thanks yall for all of the help.

Two more questions. This trans is an 88 truck trans. The direct and forward drums pistons didnt have wavy or flat steels on them, they have this steel where the inside is pitched inward, like if you sliced the top 1/4" off a funnel. I removed this and was able to fit another clutch and steel in both drums. Is this ok? It seems too easy to fit another disc in there but I figure this was used like the wavy disc in some to cushion the shift?? Sound ok?

The other thing is where the foward drum mates to the direct it uses a plastic bushing stock. The copper bushing in the kit wasnt quite big enough on the inner diameter to fit so I just reused the plastic one, it looked perfect. Any reason not to go with the plastic one?

JAKE: Your pm box is full on here, I sent you a message on your site, I need to get a kit from you for another TH400 Ive got. I left my number and email on there, you can email me or pm me here if you get a chance. Thanks

jakeshoe
Sep 25th, 09, 10:22 PM
The nylon thrust washer is fine. They act as a sacrificial component if something goes really wrong, however they always seem to come out in good shape. I rollerize this location on all the TH400's that I build so I don't use the nylon or the brass thrust washer.

Jake

jakeshoe
Sep 25th, 09, 10:27 PM
Thanks yall for all of the help.

Two more questions. This trans is an 88 truck trans. The direct and forward drums pistons didnt have wavy or flat steels on them, they have this steel where the inside is pitched inward, like if you sliced the top 1/4" off a funnel. I removed this and was able to fit another clutch and steel in both drums. Is this ok? It seems too easy to fit another disc in there but I figure this was used like the wavy disc in some to cushion the shift?? Sound ok?



Sounds like the 4L80E cushion plates.

Stock should be 5 discs in the forward, direct, and 3 in the intermediates.

It's pretty straigthforward to get 6 in the directs on a 4L80E drum, it can be tricky on the TH400 drum, I usually end up cutting the piston and the pressure plate so I don't have to use any steels that are too thin.

The TH375's used 4 clutches, but they were only used in the 70's. 1988 all TH400's got the full clutch count.

67EC
Sep 25th, 09, 10:41 PM
Sounds like the 4L80E cushion plates.

Stock should be 5 discs in the forward, direct, and 3 in the intermediates.

It's pretty straigthforward to get 6 in the directs on a 4L80E drum, it can be tricky on the TH400 drum, I usually end up cutting the piston and the pressure plate so I don't have to use any steels that are too thin.

The TH375's used 4 clutches, but they were only used in the 70's. 1988 all TH400's got the full clutch count.

Is it ok to take the cushion plate out and replaced it with a regular steel and clutch disc?

jakeshoe
Sep 26th, 09, 3:48 AM
Is it ok to take the cushion plate out and replaced it with a regular steel and clutch disc?

Yes,
It may result in somewhat firm engagement from park or neutral to reverse or drive, particularly reverse.