08/31/2026
2017 Toyota Highlander Transmission Cooler Tube Replacement
I found a leak coming from the transmission cooler tube. Apparently this is a common issue where the tube rusts and forms a pinhole leak.
The part looks easy enough to replace, but the subframe is in the way when you try to unscrew it. I don’t have the tools available to drop the subframe or jack the transmission up to make the clearance.
I have seen videos where the mechanic would bend the tube straight, tighten it onto the transmission, and then bend it back as a way around the subframe/transmission blockage.
Has anyone done this repair this way? Could it potentially weaken the metal tube? I’d prefer to DIY this job, but would like to hear from others who performed this repair.