Just bought a 2013 toyota 4runner v6 4.0L 2wd to tow a 2400 lb. single axle rig (17' CC boat). It has a SAE tow rating of 5000# We'll be using it in the flatlands of Florida and plan to keep the GCVWR within 85% of specified capacity. Dealership service writer discouraged me from equipping it with a tranny cooler, stating the high tech tranny needs to operate at certain temp (altering it may harm the unit, I was told). Other dealership writer told me it would not be necessary to install a cooler. I'm not sure why they really don't want to get involved installing one for me. I don't want to mess with a brand new car at this point, feeling it may void the warranty if something does go wrong during that period. So I plan to just use it carefully, at around 50 MPH in 4th gear. Any thoughts?
