Dorman 800-621 Transmission Line Connector for Specific Ford / Mercury Models

I have a 2006 Ford Explorer XLT with the 4.0L V6 and 5R55S 5-speed automatic transmission that developed a leak from the transmission oil cooler line fitting at the radiator. Research indicated this was likely from either a failed o-ring inside the fitting or a failed o-ring between the external mating surface of the connector with the radiator. Since I could not identify what size these o-rings would be prior to removal of the failed fitting, I went ahead and ordered two replacement fittings since they contain new o-rings and the overall price was reasonable. This Dorman 800-621 connector was listed as the replacement part from multiple sources, including Rock Auto. However, I found upon removal of the original fitting that this Dorman 800-621 connector is not an exact fit, and differs in two key ways: 1) The threaded shaft of the connector is far longer 2) There are two grooves with o-rings inside the fitting, whereas the original fitting contains only a single groove w/o-ring Since I was not familiar with the internal construction of the radiator / oil cooler within the Explorer I could not tell whether the longer shaft length would be an issue, and attempted installation. I found that it IS in fact a problem, and the connector was bottoming out on something internal to the radiator with half of the shaft length still to go. This was a problem as it precluded the crushing of the O-ring between the fitting and the radiator surface, enabling radiator coolant to leak out. I therefore removed the new fitting, used a Tekton pick set to pick out one of the o-rings within it, and then transferred both it and the o-ring from the shaft to the old fitting and re-installed it successfully. I monitored it for leaks and found none. Long story short, this item is NOT a direct replacement for the 2006 Ford Explorer XLT transmission oil cooler fitting. However, if you have a pick set handy and you're careful with the removal of the transmission oil line from your original fitting and don't damage the retaining quick-connect clamps, you should be able to swap the o-rings from this fitting to your old one and re-install it successfully.