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Time for a differential cooler?

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I recently installed a Cortex catch can for the rear axle when I installed the Watts link with their cover. I figured I was now covered for any diff fluid leakage until I ran Watkins Glen last week. I typically do 20 min sessions but this event had 45 min sessions and I had fluid all over the axle area after each run. It appeared to come out the small breather filter at the top. There was only a small volume in the actual canister which seems to make the unit useless if it doesn't actually keep the fluid contained.

So I am thinking about a diff cooler. I saw the FTB and Kohr kits. Any other options that come ready to install? Where does the fan and cooler mount on the car? I wasn't expecting to need a cooler and shorter runs will likely not require it but I also don't want to have to keep cleaning up fluid.
 
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I’ve installed the Cortex overflow on multiple cars, to include my own. They all overflowed as you described. They were replaced with a larger, trunk mounted Peterson overflow.

My opinion is if you are running longer than 25 minute sessions, you really should install a diff cooler.

Look in the how to section. There are several threads detailing differential cooler builds. The most common is a trunk mounted fan pack and pump. At least on is just a cooler mounted under the car with a trunk mounted pump.

You can build the Kohr kit yourself for less money. But, it is a good kit. One thing I would add is a Setrab in-line filter prior to the cooler.
 

Grant 302

basic and well known psychic
My opinion is if you are running longer than 25 minute sessions, you really should install a diff cooler.
This. 45 minutes is a loooong time for heat soak. If you're going to ever do that again, definitely install an auxiliary cooler and change your fluid regardless - since you boiled it!
 
You can build the Kohr kit yourself for less money. But, it is a good kit. One thing I would add is a Setrab in-line filter prior to the cooler.

I would rather spend the extra money and have a kit with everything needed to make it work so I don't screw it up. The FTB kit offers and inline filter and is less than $800 so I may end up with that. The trunk mounted option is also being considered as I don't normally do 45 min sessions. As much as I enjoyed it I also corded a pair of Conti slicks and used half a tank of fuel each run (6 runs total) so one day would have done it for me.
 

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