Rear Differential Fluid

[GNX500]

2013 with the GT500 Cover. Drained the old fluid out through the bottom drain plug. Upper drain plug sending fluid in. This is my 4th quart bottle of ROYAL PURPLE MAX GEAR 75W140 and the friction modifier. It is still not spilling out and I can dip a cloth in there a bit to try to get depth of how full it is and not getting anything. There is no leak also.

 

[msvela448]

First, check the bottle of Royal Purple... I think it already includes friction modifier... So you don't need to add any extra.

Secondly, make sure the car is on level ground... If the front end is higher (like on a driveway slope) then the fluid is against the back of the diff cover, not the nose where the fill hole is.

Third, are you filling from the hole in the front of the diff near the pinion bearing area (driver side I think)? Or are you using a top hole in the diff cover (if it has one)?

Hope this helps.

Sent from my SM-N986U using Tapatalk

 

[GNX500]

I got the car on a lift, I'm using the top plug. Bottom Plug I drained without any issues. I have the Ford GT500 Finned Differential Cover; 8.8-Inch. thanks

View attachment 387091.jpeg

 

[WJBertrand]

Use the fill hole on the side of the differential itself, not the top hole on the cover. On my 2013 GT it’s on the left side, forward to the axle tube. Fill until it over flows this hole. In your case, since there’s already too much lube in there, just remove that fill plug and let the excess drain out. Replace the plug after it stops draining and you should be good. As someone else said, just make sure the car is level.


Sent from my iPhone using Tapatalk Pro

 

[GNX500]

that did it, thanks for the help