The factory transmission cooler may be adequate for lighter loads and short distances, but towing a travel trailer, particularly a heavier one, puts significant stress on the transmission. The added heat generated can lead to premature transmission wear and even failure. A supplemental transmission cooler helps keep the transmission fluid at its optimal operating temperature, protecting the transmission's longevity.
The size and weight of your travel trailer are the key factors. If you're towing a relatively small, light trailer for short distances, you might get away without one. However, for anything heavier or for longer trips, a transmission cooler is a worthwhile investment to protect your significant investment in your truck.
