This is a step by step instructional video on how to change the fluid in a Ford 7.5 & 8.8 differential. While I’m working on a ’98 Ford Mustang, this video applies to many Ford models & years since these rear ends have been in use for decades.

I show many tips & tricks to make this job quick, easy & painless. The actual labor part of this job takes about an hour, even if you take your time. The longest part is waiting for the RTV to cure, which is 12 to 24 hours. There are gaskets available at most auto parts stores that work very well too. Use a gasket instead of RTV if you don’t want to wait for it to cure.

I also cover things to look out for and inspect while you have the differential cover off, and even find a problem with my differential in the process.

Video Instructions


To reassemble your device, follow these instructions in reverse order.

3 other people completed this guide.


Member since: 05/19/2017

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If/when adding a more powerful magnet, while also having an.. aggressive driving style, would like to recommend securing the magnet with a bit of adhesive/rtv.

Landings and/or lateral slide (drifting) can dislodge magnet, potentially sending into gears for critical failure.

Thor - Reply

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