Tranny line fittings

[sickquad]

I have a leak coming from my new tranny lines going into my new tranny. The threads are good since they are new.

Am I supposed to use a thread sealant on these? I thought that pipe threads didn't require sealing? I know loctite makes a product for threads under pressure. Any of you guys use this? Or just the white tape?

-Chris

 

[mudjunkie 82]

i was told not to put any type of teflon tape or thread sealant on the threads(acts like a lubercant) because you can turn the fitting in too far and crack the case..............

 

[ugly_blazer]

No, no type of sealant is needed. It could actually cause a leak if it is put on because it may get on the beveled(sp?) part of the fitting, not allowing them to fully contact each other. Also be sure that the mating surfaces are both very clean.

 

[sickquad]

Took them out, gave a quick cleaning, tightened them back up and no leak. Thanks for the quick help.

-Chris

 

[diesel4me]

Guess I'm not the only one suffering from"Southeast Massachussetts Tranny Line Rot Syndrome"--I have to change mine just about every year(dam DPW and their sulfuric acid salt! /forums/images/graemlins/angryfire.gif).I am seriously thinking of using copper tubing,even though its not reccomended in the gm manual(why?because they wont rust fast enough? /forums/images/graemlins/dunno.gif).They use it for air brakes and other critical uses,so why not tranny lines?.All I know is the aftermarket brake lines they sell around here (made in mexico on the tag)rust very quickly,even the coated ones I got at autozone are already rusty,and I only put them on in january! /forums/images/graemlins/angryfire.gif /forums/images/graemlins/angryfire.gif

 

[ugly_blazer]

Maybe try stainless steel braided line?

 

[diesel4me]

I thought about that---until I priced them--about 90 bucks around here,too much for me at the moment.The other reason I was thinking copper was,after getting a nasty burn when I touched one of my steel lines,I realized the lines themselves must dissapate a lot of heat,and copper would be even better at conducting the heat,and you could wrap it in a pigtail fashion(like the brake lines at the master cylinder)to get a little extra cooling out of them.
I think stainless steel brake,fuel and tranny lines should be mandatory by law,especially in the rust belt states,and the price should not be so prohibitive so people wont be tempted to skimp on safety to save money..
I also considered hydraulic hose,but I think they would hold a lot of heat instead of helping cool the tranny,and they are pretty costly too.Right now my diesel truck has a 4 inch hunk of regular 5/16 fuel line splicing the line together where my front driveshaft rubbed through it! /forums/images/graemlins/yikes.gif /forums/images/graemlins/yikes.gifI have to at least get the right rubber hose for tranny coolers on it,its hard to get it around here.And home depot has 3/8 flexible copper tubing for 8 bucks a 10ft lentgth,I can adapt that to the factory fittings with 10 bucks worth of brass adapter fittings-- /forums/images/graemlins/thinking.gif /forums/images/graemlins/thinking.gif /forums/images/graemlins/thinking.gif
Anyone else tried copper tranny lines??.I did my plow truck's fuel line with copper 5 years ago--It turned green,but its not rusty! /forums/images/graemlins/whistling.gif

 

[sickquad]

Diesel, just through the middleboro rotary past dunkin donuts there is a truck supply place on the left hand side with an amazing supply of hoses.

-Chris

 

[Ryan B.]

[ QUOTE ]
Am I supposed to use a thread sealant on these? I thought that pipe threads didn't require sealing? I know loctite makes a product for threads under pressure. Any of you guys use this? Or just the white tape?

[/ QUOTE ]

Uh, pipe threads do require sealing.. Use teflon tape or paste on NPT fittings.. (like your coolant temp sensor)
The tranny lines are 45* inverted flare fittings. With 45 degree flare fittings or 37 degree AN fittings you do not use teflon.

 

[diesel4me]

You mean Corsini's?.I used to work there about 10 years ago! /forums/images/graemlins/blush.gif /forums/images/graemlins/blush.gif.I'm currently unemployed,so thats why I'm being so cheap--well ok,I am a cheap bast$## anyway!
Didnt mean to hijack this post(sorry!).I think the original question was should you use teflon tape on the adapters for the tranny lines that screw into the tranny case?.If they are regular pipe thread,I'd say yes,but do be careful not to overtighten,I can see its possible to crack the case pretty easy,one of my TH400's cracked when I was too lazy to tap out one of the bolt holes that holds the inspection cover on,it was stripped and I thought I could get away with a 1/4 inch sae bolt ,since I had no metric ones-cast aluminum BITES!. /forums/images/graemlins/angryfire.gif

 

[Triaged]

I use the liquid stuff on everything...I HATE teflon tape.

Tape can get in and clog up the valve body...and with a temp sensor it can cause it to not ground to what it is going into (which will cause bad readings).

 

[Ryan B.]

Ah.. Now that i re-read this post...
Yes the adapter fittings will need teflon tape or paste where they screw into the transmission case because those are NPT threads in the case...
Where the hardline screws into the adapter fittings those are a 45* flare so they won't need teflon to seal up..