mtnman210
1/2 ton status
This is on my th400 tranny. What is this and what am I suppose to run/hook this to? I'm guessing is some kind of vacuum diaphragm but I have no clue what to do with it.
CK5
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Th400...what is this?
- Thread starter mtnman210
- Start date
LOL.
That would be the modulator and controls shift firmness.
There should be a vacuum line going to it, yes.
-- A
That would be the modulator and controls shift firmness.
There should be a vacuum line going to it, yes.
-- A
full intake vac from back port on intake.
This is on my th400 tranny. What is this and what am I suppose to run/hook this to? I'm guessing is some kind of vacuum diaphragm but I have no clue what to do with it.
Wow, how have you not blown that hose off there yet?
After you have your modulator hooked up, the next thing would be to get a cover over that Torque Convertor.
MTMike
1/2 ton status
do NOT hook it up to the PCV valve - don't ask me how I know. 
(in my defense, it was the previous owner who did it, I just never noticed it until it got just enough oil to alter the shift patterns).
(in my defense, it was the previous owner who did it, I just never noticed it until it got just enough oil to alter the shift patterns).
mtnman210
1/2 ton status
Alright I'll run the new line tomorrow. That probably explains the huge puddle underneath where all the fluid came out the dipstick tube seal
ok I have driven it around the block a couple times, would I have damaged anything? I'm guessing that's why I couldn't get it out of first gear
cover?.... haven't run a cover on any of my tranny/torque convertors for as long as I can remember. They seem to always be in the way of something....so they're gone.
ok I have driven it around the block a couple times, would I have damaged anything? I'm guessing that's why I couldn't get it out of first gear
cover?.... haven't run a cover on any of my tranny/torque convertors for as long as I can remember. They seem to always be in the way of something....so they're gone.
y5mgisi
1 ton status
No damage risk really. And yes that will make it not up shift. The cover will help to prevent the bell housing from cracking but i guess you could say its unnecessary.
mtnman210
1/2 ton status
that would be my problem then. I couldn't get it out of first gear and then all of a sudden it would grab second really hard.
now that you mention it, I never thought about giving some support to the housing. I'll see if I can come up with something to go across. But I really have no room.
on one truck I've got tranny linkage in the way and on the new one that's where the exhaust has to run.
now that you mention it, I never thought about giving some support to the housing. I'll see if I can come up with something to go across. But I really have no room.
on one truck I've got tranny linkage in the way and on the new one that's where the exhaust has to run.
x2
You should really replace that rubber hose and clamp with some compression fittings and hard line.
Even though that's the return line, it is still under high presure and temps.
y5mgisi
1 ton status
*hijack* anyone know really how much pressure is in those lines? It cant be too awfully much as LOTS of people get away with this kind of setup. Agreed though that it is the improper way of doing it and should be changed.
tourdog
Registered Member
the vacum mod yes should be hook to vac but will not hurt anything not while back i was drag raceing trucks would shut the vacum off for raceing then turn it on again to drive home trans will shift but ****s off govner in trans.
It's not that much pressure, I did the same thing many times when my steel lines broke, I ended up putting copper which lasts longer since it's flexible and will not break.
All the auto coolers I bought came with hose and clamp.
BILTIT
1/2 ton status
~ 50 psi average.
Is that trans hose or fuel hose? The main thing is that fuel hose is not rated for the temp of trans fluid, that is why they make specific hose for transmissions. Steel line is the best and not hard to do.
Is that trans hose or fuel hose? The main thing is that fuel hose is not rated for the temp of trans fluid, that is why they make specific hose for transmissions. Steel line is the best and not hard to do.
Trans coolers will come with the propper hose and barb fittings to install them. I haven't seen one that recomends cutting the line and just slipping the hose over the end.
Even if you do use transmission-rated hose, it's a crappy place to put it. The exhaust manifold down there can melt the stuff, and then you have a transmission-fluid fire under the hood. Ask me how I know 
The one time I *MADE* it to BlazerBash, I almost made it home and then that...
-- A
The one time I *MADE* it to BlazerBash, I almost made it home and then that... -- A
mtnman210
1/2 ton status
ok I can't for the life of me find a vacuum port on the back if the intake manifold. Am I just blind or retarded or both. The motor is a Cadillac 500
Any manifold vacuum port will work. You didn't hurt anything by not having a vacuum line to it, besides your wallet. The transmission just thought you were at wide open throttle at all times, raising your shift points and firmness and decreasing your mileage.
There is also nothing wrong with running rubber transmission line. Just make sure it is actually for oil, not vacuum line. They sell specific hose just for that application. As for the guy that said he has never seen a cooler kit that recommends cutting the line and slipping hose over it, then he hasn't seen many tranny cooler kits.
Martin
There is also nothing wrong with running rubber transmission line. Just make sure it is actually for oil, not vacuum line. They sell specific hose just for that application. As for the guy that said he has never seen a cooler kit that recommends cutting the line and slipping hose over it, then he hasn't seen many tranny cooler kits.
Martin
