I have an '82 and an '85 Suburban. Both are 1500's with V8's and AT. Both have had some type of engine swap so I don't know what is original. The fan clutch went out on the '85 I drive every day so I swapped the fan and clutch from the '82. Question - the fan on the '85 had 5 blades with an irregular spacing and the '82 had 6 blades with more regular spacing. Which one should I keep on the '85 when I sell the '82?
Neither truck is worked real hard so I don't need maximum cooling. I wonder which fan type is the later model and why they changed. More cooling? Less noise? Space to get to the bolts?
Thanks, Noell

From what you describe it's six of one, half a dozen of the other. More blades is usually more airflow. My '90 has always run so cool I usually fit the lightest-duty fan clutch I can find when I replace them (truck has almost 400,000 miles), keeping the original stock fan.

If you don't mind a bit more noise you can replace the fan clutch with an aluminum spacer and longer bolts, then install a lightweight fiberglass or aluminum flex fan. They turn all the time but feather themselves out of the airstream at higher rpms. Supposed to be good for about 15 extra hp.