Upgrading stock trans cooler. Hayden? How to anywhere?

Mossyoakglock · June 18, 2015

I'm wanting to upgrade my stock trans cooler to the Hayden unit. Is there a write up anywhere for a GMT-900? What parts do I need? I know I'll have to fab up a bracket which is no problem.

I'd like to keep all the haedlines and use adapter fittings as well. What lines from the truck go into which ports on the cooler?

Chris · June 18, 2015

I would say follow the lines. Line from top radiator port goes to cooler input and cooler output goes to the trans.

Mossyoakglock · June 18, 2015

I already have the factory cooler so i won't need to run anything from the radiator. When looking at the new cooler, which is the inlet and which is the outlet? Is the left the in and right the out?

Everything else I've found says that the easiest way is to just use some rubber lines but are there any factory-style fitting/adapters that will work (Hayden #390)? Any how much more fluid capacity is there with the Hayden 679 vs the stock? Want to make sure I add enough fluid back in.

I was also looking at the Tru-Cool LPD4544. It looks to be almost identical to the Hayden but it was the bypass to allow the fluid to heat properly. Is one better than the other? I live in TN so rarely see anything in the teens during winter but in the summer we can see 90+ for days/weeks (it's actually been 95 - 97* every day this week with high humidity).