Hayden 679HD install

I also used the 679 cooler and routed "out" line from radiator to the Hayden and then back to tranny. If you were looking to bypass radiator I wouldn't be concerned if you step to the nearly sq. ft. 679.

I also installed a coolant sensor on OUT line of transmission so I can see the high temp fluid reaches in transmission... rest assured, the 679 does the job intended (imagine 22RE motorhome climbing mountains in summer).

'87 22RE