What size hose is required?

[Steve Cole]

What size hose/line are you running to the (TH400) tranny vacuum modulator? The nipple on my modulator looks like it takes about a 1/8" - 3/16" hose. I wanted to use a 90 degree fitting coming out of my manifold (3/8" NPT - 1/8" or 3/16" nipple but the smallest I have found is 1/4" nipple and only in straight, not 90.

I was considering running a hard line with a short section of rubber on both ends but there is no good place to clamp the line along the way.

Thanks,

[BlackedOut67shorty]

Factory th350 used hard line with rubber ends from factory, wouldn't doubt th 400 has their own hrs line setup
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[Wrenchbender Ret]

They use 1/4 in hose. Usually the factory runs the hard line down along the dipstick tube but I don't remember what side the mod. is on on a 400.

[BlackedOut67shorty]

I belive its on the passenger side if someone can clarify
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[JointTech]

its on the passenger side yes

[Steve Cole]

Anyone have a pic of how this line is routed? It doesn't seem like there is anywhere to clamp it along the way. JointTech is right, it is on the passenger side.
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[FirstOwner69]

On my 69 3/4 ton with 350 engine and TH-400 the line is steel and is held to the modulator and vacuum "T" with very short rubber hoses. In fact, the "T" end of the steel line is more of a nipple that loosely slides into the "T" with the hose creating the necessary seal function. The line should have a tab welded to it that is attached to one of the top bell housing bolts along with the trans dipstick.

Here's a link for the line made for my truck with a stock intake manifold or aftermarket manifold with the vacuum port in the same location. Interesting that the application is only for 69/70.http://www.getdiscbrakes.com/ttv6905

I'd post some pictures, but the changes made to the forum a couple days ago won't allow me to do so.