why is 03-04 viscous fan different?

[mark.kellgren]

I have an 04 and realized today my viscous is shot. Went to order another and to my surprise, found out the regular removable viscous clutch ends at 02, and for last 2 years, the entire fan assembly must be replaced. My question is why the F they did that, and is the superseded fan-clutch compatible with the last 2 years? Just ordered a replacement assembly so now I'm just curious, given the engine is the same.

 

[DiscoPhoto]

Likely realized it needed more cooling capacity. Water pump is the same either way

 

[discograham]

'03 and '04 are 4.6 liter compared to the 4.0 in the earlier Discoverys

 

[best4x4]

Install a dorman 620-112 fan blade and hayden 2991 fan clutch and call it a day.