i want to change out my rear end fluid how bad is it to do,what kind should i get and how much ,what kind of friction modifier and how much,do i need a new gasket???????????? etc.....thanks

 

easy job. get a drain pan,remove the cover bolts and pry the cover off,let all the fluid drain. clean the mating surfaces,I use brake cleaner. use rtv sealant,no gasket needed. use 75/140 or 85/140 GL5,the GL5 stands for synthetic,youll need about 6 pts for the 8.8 diff. add 4oz. of friction modifier.

 

I hope I don't get burned at the stake for heresy but DANA (the differential maker) recommends using MOPAR Friction Modifier in their differentials.
Dana Corp makes most of Ford's differentials.

 

i also heard to go MOPAR for the tranny fluid also???????

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pacific green 97 f150 4.6l..reg cab flareside 150XLT ,ROUSH suspention down 3 fr and3.5rear,3.55LS,snug lid,carpeted bed, painted tailight accents,4x4 grill &bumper,k&n,SUPERCHIP(THANX MIKE),ram air kit,valvoline synthetic,accel super stock wires,platinum plus4 plugs,flow master muff,blue halogen bulbs, speed-glo dash,carbon fiber gauge accent,..."#6 sticker!!!!"
STEREO:eclipse head unit ,boston seperates ,orion amp, pioneer amp,2-orion 12's,custom box by me!,sony adjustable crossover,1 farad cap&way to many cd's

 

where do you recommend getting the synth. fluid??????? i know it's $$$$$$$$$

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pacific green 97 f150 4.6l..reg cab flareside 150XLT ,ROUSH suspention down 3 fr and3.5rear,3.55LS,snug lid,carpeted bed, painted tailight accents,4x4 grill &bumper,k&n,SUPERCHIP(THANX MIKE),ram air kit,valvoline synthetic,accel super stock wires,platinum plus4 plugs,flow master muff,blue halogen bulbs, speed-glo dash,carbon fiber gauge accent,..."#6 sticker!!!!"
STEREO:eclipse head unit ,boston seperates ,orion amp, pioneer amp,2-orion 12's,custom box by me!,sony adjustable crossover,1 farad cap&way to many cd's

 

You should be able to get the 4 oz bottle from your friendly Chrysler Parts man.
Look in the yellow pages for one near you...