Hypothetical question about transmission cooling lines

[JimShine]

What are the possible scenarios presented if the transmission lines are banged up and restricting flow of the fluid to the radiator? What sort of issues would crop up over time? I am not thinking total lack of flow, but lets say reduction of 50% or more of fluid flow.

[John_Kunkel]

The cooler lines not only transport fluid to and through the cooler(s), but the fluid returning to the transmission is the main supply of lubrication for the rear support and all of the mainshaft components such as the planetary gears, thrust washers, etc.

Depending on the severity of use, a 50% reduction in flow could raise the fluid temperature significantly and eventually lead to excess wear on the maiinshaft components.

[JimShine]

How about wear and or burnout of items like the belts and clutchpacks?

[John_Kunkel]

Belts?

Bands and clutches get their lube from a different source but a rise in fluid temperature would eventually affect them too.

[JimShine]

Update Got the transmission out. One line was totally crimped off, the rest had many severe dents all along them. The transmission shop didn't bother replacing the lines when they did the rebuild. Not sure if this was the only reason why the thing crapped out, but I have to believe it was atleast part of the problem.

[TylerCharger69]

Sounds like it was the problem....Of course...one line is send  and one is return....if the send  line is crimped....the tranny  is not getting proper lubrication...if the return line is crimped.....it can cause dry-sumping...depending on the restriction...and yes...it WILL  make the tranny  run hotter

[JimShine]

I didn't get to deep as the more we poked around, the more obvious it was I was charged for a full rebuild for just fixing reverse, a new torque converter and gaskets. I was angry, so I gave it to a guy who was looking for things to scrap. It feels good to get that $1K thorn out of my side.

Last fall I had a 1968 Sport Fury drivetrain given to me. It was supposedly low mileage and stored in a garage since the mid 90's. So, my buddy took a chance and we took that tranny off and inspcted it. Fluid was clean, very little metal shavings in the pan, so we gave it a shot and it was worthwhile. Shifts like new. Super tight and smooth. Way better than the rebuilt one ever did.