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Grrr vacumn modulation sucks!!!!!!

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Old Nov 26, 2007 | 07:03 PM
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Default Grrr vacumn modulation sucks!!!!!!

I just installed a TH-400 that still had a vacumn modulator, that **** sucks!!!!!

The car bounces off the limiter then it shifts then it won't catch 3rd until I let off....so mad I even wasted the time to put the tranny in like that.

RMVB with T-brake is getting ordered ASAP


Marco
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Old Nov 27, 2007 | 02:10 AM
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Go through the normal checklist first. Right fluid level? Modulator hooked to a true vacuum source? What this transmission just rebuilt? I have built hundred's of TH400's "all with vacuum modulators" and not have the problem you are describing. Need more information here?
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Old Nov 27, 2007 | 04:22 AM
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I don't have a vacuum line hooked up
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Old Nov 27, 2007 | 06:19 AM
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That's a place to start.
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Old Nov 27, 2007 | 08:52 AM
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Originally Posted by Krazy98Z28
I don't have a vacuum line hooked up

Complaining about a vacum modulated trans with no vacum line not shifting right would be like unplugging an electronic trans, then moaning because it doesn't work right.
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Old Nov 27, 2007 | 11:57 AM
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Well either way it still sucks!

I'm converting to RMVB in a couple weeks
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Old Nov 27, 2007 | 12:22 PM
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Originally Posted by Krazy98Z28
Well either way it still sucks!

I'm converting to RMVB in a couple weeks

just throwing in a reverse manual valve body without building the trans for it is a waist of time also just so you know.
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Old Nov 27, 2007 | 05:00 PM
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Originally Posted by jay_lt4
just throwing in a reverse manual valve body without building the trans for it is a waist of time also just so you know.

Explain why it would be a waste of time??
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Old Nov 27, 2007 | 07:45 PM
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If you are going to put a trans brake in your car you will need to disassemble the trans anyways. There are mods that will have to be done to the direct drum and also the pump with some brakes. Just a heads up.
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Old Nov 27, 2007 | 11:44 PM
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Actually if you don't have the vaccum line connected IT CAN'T SUCK!!!
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Old Nov 28, 2007 | 12:01 AM
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Originally Posted by big wally 55
Actually if you don't have the vaccum line connected IT CAN'T SUCK!!!
I like That
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Old Nov 28, 2007 | 05:21 AM
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:JEST:

I knew I shouldn't have installed it

The original plan was for me to bring the tranny to my tranny guy, but a friend of mine convinced me that he could do it on the car. Problem is my tranny guy travels because he is a GM instructor, so it's tough to get ahold of him, so I just made a call to install it without consulting him. Oh well, nothing like paying for more labor for stupidity.

Memo to self, never listen to you friends
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Old Nov 28, 2007 | 04:27 PM
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a while ago i had a rmvb car in a stock TH400 trans... it never worked right.

get the trans built for it.
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Old Nov 28, 2007 | 05:09 PM
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do you have a TV cable on that bad boy?
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Old Nov 28, 2007 | 05:15 PM
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Originally Posted by FiredUpZ28
do you have a TV cable on that bad boy?
400s dont have TV cables they have a kick down solenoid in place of The kickdown cable
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Old Nov 29, 2007 | 04:35 AM
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Originally Posted by Bryan @ Speed Inc.
a while ago i had a rmvb car in a stock TH400 trans... it never worked right.

get the trans built for it.

I'm going to talk to a few tranny guys I know, luckily we have some really good guys in the area. Just sucks I have to pull the trans out
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Old Nov 29, 2007 | 06:48 AM
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Umm,whats the problem with just running a vacuum line?
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Old Nov 29, 2007 | 07:43 AM
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^^^+1 on that...
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Old Nov 29, 2007 | 11:04 AM
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Originally Posted by performabuilt
400s dont have TV cables they have a kick down solenoid in place of The kickdown cable
cool, I learn something new every day Or every hour on here
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Old Nov 29, 2007 | 03:17 PM
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Originally Posted by Slowhawk
Umm,whats the problem with just running a vacuum line?

I planned from the get go to put in a RMVB. The guy that installed my tranny said it can be done with the tranny installed in the car. So I made the decision to just install the tranny.

There's no problem with running a vacuum line, I just don't want to rely on the transmission to shift gears for me. I want to shift myself


I'm just pissed off that I have to pay more labor because I'm an idiot
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