Differential Fluid Change Question

[Grafanton]

In anticipation of a track day next weekend (Summit Point), I decided it was well past time to change the differential fluid.
Checked the owners manual for the capacity (1.5L), bought the appropriate fluid which came in 1L bottles, so, I bought two.
Drained the fluid. Replaced the plug and proceeded to get both bottles into the diff without a drop coming out of the fill hole.:shrug:
Have I just over filled my diff? Is it under filled since nothing come out of the fill hole?

It looks like I drained roughly 1.6L from the diff.

Sponsored

 

[Optimum Performance]

In anticipation of a track day next weekend (Summit Point), I decided it was well past time to change the differential fluid.
Checked the owners manual for the capacity (1.5L), bought the appropriate fluid which came in 1L bottles, so, I bought two.
Drained the fluid. Replaced the plug and proceeded to get both bottles into the diff without a drop coming out of the fill hole.:shrug:
Have I just over filled my diff? Is it under filled since nothing come out of the fill hole?

It looks like I drained roughly 1.6L from the diff.

Should be roughly 8-9mm below fill hole. The diff holds 1.5+.118 for additive. So 1.6L.

 

[Impulsed7]

Yea, if you overfill, you'll get a bit of a mess at that first track day. I have two output seals to replace now...

 

[Ricky Nelson]

Has anyone tried the Red Line Oil diff fluid? I heard it's really, really good. This was told to me from a bunch of endurance racers.

 

[Impulsed7]

Redline is always good stuff. just a bit pricey for something I change out so much.

 

[NightmareMoon]

Has anyone tried the Red Line Oil diff fluid? I heard it's really, really good. This was told to me from a bunch of endurance racers.

I'm running redline gear oil 75W140, but I haven't run that many events on it yet.

 

[wildcatgoal]

How many miles on your car that you felt the need to change the differential fluid?

 

[Optimum Performance]

How many miles on your car that you felt the need to change the differential fluid?

Because he doesn't want the temp warning during his track day I would assume.

 

[wildcatgoal]

Not the question I asked. How many miles.

Is he (or anyone) guaranteed a temp warning simply for going to a track day? I mean better safe than sorry but... a car that hasn't even come close to the normal fluid change interval probably doesn't need a diff oil change to go to an HPDE event. Countless people who have gone and done HPDE and been totally fine on stock fill.

 

[Optimum Performance]

Not the question I asked. How many miles.

Is he (or anyone) guaranteed a temp warning simply for going to a track day? I mean better safe than sorry but... a car that hasn't even come close to the normal fluid change interval probably doesn't need a diff oil change to go to an HPDE event. Countless people who have gone and done HPDE and been totally fine on stock fill.

Yes, 2016+ typically will give warning in session. Some people after 3 laps, some at the end of a session. Several people change to 140 to delay the warning.

 

[wildcatgoal]

I did a full track day at 80+ degrees and never saw a warning at Atlanta Motorsports Park.

Guess I gotta get on it harder...

But I do have BG oil back there, so... there ya go.

 

[tedj101]

How many miles on your car that you felt the need to change the differential fluid?

Ford says to change the diff oil after one hour of track time and every 8 hours of track time after that. I do this religiously (using RP 75-90) and no longer have problems with the diff overheat warning. Given Ford's recommendations, I think they know that they have a heat problem with these diffs...

Regards,
<TED>

 

[wildcatgoal]

Haha, right. So I'm going to go do four 15 min. sessions - then in the parking lot go change my diff oil real quick, Ford? Sure - seems logical.

I mean I'm not at every event, but I have never seen anybody changing diff oils midway through an HPDE I have ever been to (driving or just hanging out). Just seems goofy diff oil has to be discared after 1 hour of track time after who knows how many miles before it got there. Then after another 8 hours accumulated? Meanwhile, I can tow a heavy trailer on my truck every day and am told not to change the diff until 30K miles in those conditions.

So confusing.

 

[tedj101]

It's different use and a different vehicle. How much lube does your truck diff hold? The Gen 6 Mustang has half the diff lube capacity of the Gen 5 and before due to going to a fully independent rear end. That has put real strains on the diff's capacity to absorb the amount of heat that it does at a track event.

<TED>

 

[Impulsed7]

Ford's 1 hr suggestion is for the OE fill. its then every 8 hrs of track time after that, or for me, every other weekend.
Also, a live axle has to lubricate the shafts, hence the extra capacity...

Sponsored