Thread Sealant For Transmission Lines?

[Fitz98]

Is thread sealant supposed to be used on the transmission lines fittings going into the radiator? If so, what do you use?

 

[Oro_O]

Does the fitting you are working with not have a compression washer or rubber sealing gasket? Most do.

 

[Trav]

No, they are usually a flared fitting or use an O ring with a clip depending on the make.

 

[mattd]

They should be flared... so no

 

[Chris142]

Many use a pipe thread and it needs a sealant. What are you working on?

 

[DBMaster]

I've always put some teflon tape on the threads. Even if it's not needed it ensures that the lines can be removed pretty easily in the future.

 

[RF Overlord]

The factory service manual for my 2003 Crown Victoria specifically advises AGAINST using Teflon tape on the fittings at the transmission. Says it could cause the case to crack. YMMV.

 

[Wagonmaster261]

When I replaced the radiator on my 94 F150, the transmission cooler lines wouldn't stop sleeping until I put a little of the liquid Teflon on the threads. Been good for the last 3-4 years now.

Pieces of the Teflon tape could get lose and cause issues, but the liquid stuff seems to be better. Just a small dab, and the act of threading it in distributes it well. The fittings on the replacement radiator might not be an exact match to the fittings on the lines.