best differential fluid 98 GT?

[DTNODYA]

I need to change my differential fluid .. (maintenance) and was wondering what the best fluid is. Also do I need friction modifier? What are some good brands and weights (preferably synthetic)? I searched but we know how that goes. Thx guys. I know what the Haynes manual says but want some personal opinions.

- J -

 

[03ghoststang]

i use Royal Purple as far as the weight goes you can use 75-140 or 145 cant remember or 75-90 full synthetic

 

[Tally_4.6]

I used Pennzoil 80-90w with the 4oz of friction modifier.

 

[stangGT97]

I used Pennzoil 80-90w with the 4oz of friction modifier.

same here, no problems to speak of thus far

 

[Pennywise2]

I changed my differentail fluid at 60K miles with Royal Purple 75W90
gear oil. After I changed it the differentail I could feel that it ran smoother
and seemed quieter.I am very happy with the Royal Purple gear oil. If you
have a 98 GT I recommend useing the 75W90.

 

[DTNODYA]

Cool, thx for the replies. Is there anywhere that sells Royal Purple or do you have to order it of teh interwebz?

 

[Pennywise2]

I got my Royal Purple 75W90 from www.jegs.com

 

[loosescrew79]

Got my royal purple from my local speed shop. They had it in stock

 

[hognutz]

I would just use the 75-140 royal purple. by the time you buy a good synthetic and the modifier the cost is pretty close to the same.

you can go to royal purple's website and find the closest dealer or order online.