I removed my 2765 jag fan clutch this weekend. Measured it next to the new 2947 fan clutch. Noticed immediately that the new heavy duty 2947 is 1/4 inch longer total, so the clutch will be closer to the radiator. The measurement information shown on the Hayden website (posted above) shows much less overall length difference. Just wanted everyone to know, in case your radiator to fan clearance is tight already. The new 2947 fan clutch will work on my car, but is MUCH tighter clearance now. Hopefully installing will help keep the engine cooler, but have not run the engine yet, still working on re-installing the radiator....