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Differential fluid change good idea?

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I think my dads in the mood to work on the subi over the weekend, going to do all 4 discs, front pads, all the brake lines, and 1 front CV, going to be fun. but now i cant remember where i saw this but someone said they changed there diff fluid to royal purple fluid, and it ran more smooth, and quicker all around, an quieter? are there different gear oil weights? If so what should i run? And whats a good suggestion for diff fluid? thanks!

You put in the weight that is required by the factory. It never hurts to change the fluids.

 

nipper

  • Author

ok thanks, so whats the recommended weight:rolleyes:

 

got any recommendations for fluid? or is royal purple good? jump wondering though, i think i changed the rear diff fluid about 3 months ago, it was quieter, and more smooth in the rear, when im in the back, but in the front seems more ruff:-\. So im thinking i should change both fluids at the same time.

ok thanks, so whats the recommended weight:rolleyes:

 

got any recommendations for fluid? or is royal purple good? jump wondering though, i think i changed the rear diff fluid about 3 months ago, it was quieter, and more smooth in the rear, when im in the back, but in the front seems more ruff:-\. So im thinking i should change both fluids at the same time.

 

same weight as the rear (or are you going to make me look it up)

 

nipper

  • Author
same weight as the rear (or are you going to make me look it up)

 

nipper

 

sorry but yes, PLEASE, i had my dealer change the fluid so i have no clue, thanks nip!

but the 75's work good too. :lol:

 

Sure Mr show off with your three stars .....

 

 

nipper

i use 80w-90, so ha :-p

and yeah, change it, it's good for it, i wouln't be suprised if it comes out like honey... nice & black honey ;)

  • Author
i use 80w-90, so ha :-p

and yeah, change it, it's good for it, i wouln't be suprised if it comes out like honey... nice & black honey ;)

 

acually it does look like honey:mad:, when i pulled the dip stick on the front diff, it looks like honey, and the rear diff is new fluid, i guess i wont see a huge improvment, but ill bet ill see a difference when i install my new brakes and brake lines, and change my bad CV:)

Go for it and change it. generally I think the suggested is like 80w90 front and 75w90 rear. i run amsoil severe gear syn 75w140 in both suby's. gear oil may not look 'dirty', but it can shear so dirt (shavings/etc) is not the only factor.

  • Author

Well, i was thinking a better quality fluid might fix the whining whenever i get off the gas, by the way, does the rear diff cause this noise? or torque converter?

Well, i was thinking a better quality fluid might fix the whining whenever i get off the gas, by the way, does the rear diff cause this noise? or torque converter?

 

TC no. . Differentials ROAR and the volume increases with speed. Its un mistakable in its sound.

Now explain this whinning....

 

 

nipper

  • Author
TC no. . Differentials ROAR and the volume increases with speed. Its un mistakable in its sound.

Now explain this whinning....

 

 

nipper

 

ok, when ur driving its really smooth, but as soon as you get off the gass you hear a whining noise, not that its super loud, but its there, but it sounds like its downshifting once i get off the gas.

ok, when ur driving its really smooth, but as soon as you get off the gass you hear a whining noise, not that its super loud, but its there, but it sounds like its downshifting once i get off the gas.

 

frt or rear. does it change with road speed or engine rpm. does it change turning left or right.

 

nipper

  • Author
frt or rear. does it change with road speed or engine rpm. does it change turning left or right.

 

nipper

 

really hard to tell, but id say the rear, and it sounds about the same at any speed, except below 40, but it only does it, when you have been driving all day so all the components would be hot. But when the car is cold, i dont think i can hear it. I also have a bad CV boot in the front.

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