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GT350 Differential Fluid Change

I can't seem to find any "how-to" threads on changing the diff fluid in the 350. I looked at the cars manual and it just specifies the amount and what oil to use. I think it would be pretty straight forward, pull the drain plug and I believe one other hose to drain some more oil from the pump and then refill. Anyone find any videos online or can maybe point me to a thread on the forum?

Thanks,

Adam
 
You may want to cycle the pump as well.
 
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Rick,

Is there a how to video somewhere? I know I can figure it out but might save me a trip to the auto part store if I forget something. Also, what fluid are you guys using?
 

steveespo

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GT350 Differential Fluid Change

Miller oils 75w140NT. The best gear lube out there. Used by many IndyCar teams. Pure synthetic base GL4/5 Ford manual gives the specific amounts to fill, its a lot less than we are used to, hence the high temps. There is a forum member who is making jumper harnesses to force the pump is to drain and fill like the manual describes. Not having a diff cooler I don't know if there is another way. @black boss ?


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Flyboygsxr said:
I can't seem to find any "how-to" threads on changing the diff fluid in the 350. I looked at the cars manual and it just specifies the amount and what oil to use. I think it would be pretty straight forward, pull the drain plug and I believe one other hose to drain some more oil from the pump and then refill. Anyone find any videos online or can maybe point me to a thread on the forum?

Thanks,

Adam

@Flyboygsxr Adam, Remove the lower hose to drain, I then slightly over-filled to compensate for the small fluid loss from the lower hose. I did not cycle the pump and would be careful doing this with cold fluid for fear of stressing the pump. This obviously doesn't flush the fluid in the cooling circuit, but leads to an accurate re-fill, and I'm switching fluid every 10-15 track hours which is probably conservative...
 
VoodooBOSS said:
This looks like it. Looks like it costs more on Amazon.

I'm curious what Vorshlag uses. @modernbeat

http://performanceracingoils.com/crx-75w140-nt-p-44.html

CRX-75w140-NT.jpg

After being a non-believer for a decade, I started using Motul oils and I'm sold. They make a lot with oddball specifications to match unusual applications, like Porsche motor oil, Nissan GTR trans oil, some specialty BMW oils and such. When I'm looking at something that calls for an unusual spec, I call Motul and get a recommendation.
 

steveespo

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I agree with Jason on Motul oils, I run 300V Motorsport engine oils, but stand by my recommendation of the Miller Oils gear lube. I have seen the temperature results on both my 2011 and 2016 cars, so much so that I have removed the diff cooler from my 2011 car.
Steve
 
VoodooBOSS said:
I haven't changed the fluid yet but I may try the fluid @voodoo child21 recommended. Also if you turn the car over with the gas pedal floored the car won't start but that should cycle the diff pump. @tim

FYI my diff temps got very hot at my last track day so that's why I'm considering a thicker fluid.

Most of the scan tools now have the PID updates to allow this. It's why the harness I made is kind of obsolete. I believe the pump cycles with ignition on if anyone wants to confirm.
 

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