Transmission Oil Cooler Lines - Replacement

darleyhavidson · March 4

I have a 2022 GMC Sierra 2500HD SLT with the 6.6 gas motor. I am looking to replace the transmission cooler lines.

Part description/number:Transmission Fluid Cooler Inlet and Outlet Pipe Assembly - GM (85584364)

Does anyone have any advice or tools I might need that isn't obvious? Any routing issues when trying to install the new lines?

Prefer to have all the supplies and tools ahead of time and not get caught short during the replacement process.

Another JR · March 4

I haven’t had to replace mine yet, but I have done several oil cooler line replacements over the years on my 93 K2500 for the same issue - leaking at the swaged joint between the hose and solid parts of the line. I don’t know if these transmission lines have the same quick assembly fittings (notice I don’t call them “quick release”) at the transmission that the older oil lines have at the filter block, but if they do you want to make sure you know how those work and have an appropriate tool to release the old ones.

davester · March 5

take pics before you remove the old line, so when you are installing the new line, you know where it goes under something and where it goes over (or side to side). Probably still uses the little retain clips setup, so you need a small screwdriver to pry off the plastic cover, then a pick to hook out the retaining clip.

If the new lines don't include new retaining clips, buy the new ones before starting the job, as they are to be replaced if you pull them out (course, I have sometimes reused them, but GM says to always replace). And be careful with pushing the plastic covers over the fitting/clip, as if you bust it, you need to pull it apart and it's a hassle to find a new one.

Make sure you get the new line aligned with the fitting, and then push it straight in until the retain clip snaps. Be sure to pull on line to make sure it is being retained.

carkhz316 · March 5

Its fairly straightforward. You'll have to lower (not remove) the front diff to get them out and back in.

darleyhavidson · March 5

14 hours ago, davester said:

take pics before you remove the old line, so when you are installing the new line, you know where it goes under something and where it goes over (or side to side). Probably still uses the little retain clips setup, so you need a small screwdriver to pry off the plastic cover, then a pick to hook out the retaining clip.

If the new lines don't include new retaining clips, buy the new ones before starting the job, as they are to be replaced if you pull them out (course, I have sometimes reused them, but GM says to always replace). And be careful with pushing the plastic covers over the fitting/clip, as if you bust it, you need to pull it apart and it's a hassle to find a new one.

Make sure you get the new line aligned with the fitting, and then push it straight in until the retain clip snaps. Be sure to pull on line to make sure it is being retained.

Appreciate the rundown.