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Do manual trans and diff oil needs to be changed ?

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Good day everyone,

I have a 13 boss 302 and im wondering if manual trans oil needs to be changed or just check if needs refilling ?

Same question to differential oil.


Mad Hatter

Gotta go Faster
Santiago, Chile
If you track the car, change the transmission oil every season.. the MT82 can get very very in hotter then the engine.

Diff oil can last longer but it really depends on how you are using the car.

Bill Pemberton

0ld Ford Automotive Racing Terror
Exp. Type
Time Attack
Exp. Level
20+ Years
Blair, Nebraska
I would definitely change the fluids just to be safe, since you could have the original fluid in both areas. If you track your car I would consider changing your fluid in both your tranny and diff every 4-10 hours of heavy track usage. I agree with Patrick Stapler and these periods are suggested by Ford Performance for their race cars and though you may not be quite as aggressive fluid changes are cheap insurance and one should not cut corners on diffs or trannies because they think they do not need to be changed as often as motor oil ----- maybe not but through away the warranty recommendations as those are for just poseurs and grandmas, ha!


Cones - not just for ice cream
Exp. Type
Exp. Level
20+ Years
Pay attention to what type of gear oil you need for the differential - the non-Torsen (clutch-type) limited slip diff takes a Limited Slip / Friction Modifier additive (or gear oil with one included). If you have a Torsen, then you don't need an LS additive. Using an LS additive in a Torsen can reduce noise in tight turns at slow speeds, but it also reduces the torque bias so it doesn't perform as well on track.

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