I want to change the fluid in my '98 F150 2 wheel drive but I'm not sure which fluid to use. When I got the truck, the previous owner told me that he put a limited slip differential out of a mustang on the truck. The cover has 10 bolts on it and these are the numbers on the front side of the housing ' 17 AF A' (the 17 and the last A are in circles) and 'F71W-4025-AC'. Can anyone help? Thanks.

 

Most 8.8 rearends have Synthetic 75w140, I have used them all I prefer 75w140 Motorcraft and Motorcraft Friction modifier On the rear cover seal it with Permatex 25224 The Right Stuff