C6 oil cooler?
Race Director
Joined: Sep 2007
Posts: 16,557
Likes: 2,108
From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
I've been down this path somewhat, I have a '12 GS with the A-6 so no EOC or diff cooler. It was okay for the start of this years hpde season but as the season progressed and my skills increased I quickly found I needed an EOC.
I tried a DeWitts radiator with EOC/TOC (engine oil cooler/transmission oil cooler) and found the EOC/TOC barely adequate at my skill level so now I'm looking at external EOC/TOC options. I would like to get a Differential oil cooler too but the packages I see in the aftermarket are either too expensive or not palatable (don't want to add an electrical pump) or very difficult to find parts for (European version of the C-6's come with a differential cooler).
Gearhead is correct about oil temps being too low with the Z-06 oil cooler for daily driving.
With Mobile 1 synthetic oils, 260 is about max you want to see.
I've heard comments the A-6 can run pretty hot without self destructing, though it probably shortens the life of the transmission. The issue is the differential temperatures. Comments heard third (or fourth party) was the A-6 for track duty will fail before the un-cooled differential will -from GM.
I contacted GM through the forum, they said the A-6 should run +/- 20 degress of Coolant temps and be okay. The DeWitts radiator does a great job keeping engine coolant temps down but not so great with EOC/TOC.
Don't get me wrong, I love the DeWitts radiator, very high quality build.
My next plan is to add external EOC/TOC cooling via heat exchangers. I want to add an EOC before the oil hits the radiator EOC. This will serve to modulate EOC temps such that the oil will warm up to good operating temps for DD use and still have capacity for added heat input during track days plus remove some of the heat load seen by the radiator during track days (not that its really needed so far). For the TOC, since the transmission seems to be a heat sink for the differential, I want to add an external TOC after the radiator TOC supplying cooler oil to the transmission. Ideally, a DOC should be installed too, just haven't figured out an economical way to do it yet. What I would like to use is a Z-06 diff cooler setup with the A-6 ratio's. There is a kit for adding a mechanical external pump to the diff but it costs somewhere in the neighborhood of 1200 to have someone do the install bringing the total package to 3k - the approximate cost of a replacement differential.
Would love to hear any additional thoughts...
I tried a DeWitts radiator with EOC/TOC (engine oil cooler/transmission oil cooler) and found the EOC/TOC barely adequate at my skill level so now I'm looking at external EOC/TOC options. I would like to get a Differential oil cooler too but the packages I see in the aftermarket are either too expensive or not palatable (don't want to add an electrical pump) or very difficult to find parts for (European version of the C-6's come with a differential cooler).
Gearhead is correct about oil temps being too low with the Z-06 oil cooler for daily driving.
With Mobile 1 synthetic oils, 260 is about max you want to see.
I've heard comments the A-6 can run pretty hot without self destructing, though it probably shortens the life of the transmission. The issue is the differential temperatures. Comments heard third (or fourth party) was the A-6 for track duty will fail before the un-cooled differential will -from GM.
I contacted GM through the forum, they said the A-6 should run +/- 20 degress of Coolant temps and be okay. The DeWitts radiator does a great job keeping engine coolant temps down but not so great with EOC/TOC.
Don't get me wrong, I love the DeWitts radiator, very high quality build.
My next plan is to add external EOC/TOC cooling via heat exchangers. I want to add an EOC before the oil hits the radiator EOC. This will serve to modulate EOC temps such that the oil will warm up to good operating temps for DD use and still have capacity for added heat input during track days plus remove some of the heat load seen by the radiator during track days (not that its really needed so far). For the TOC, since the transmission seems to be a heat sink for the differential, I want to add an external TOC after the radiator TOC supplying cooler oil to the transmission. Ideally, a DOC should be installed too, just haven't figured out an economical way to do it yet. What I would like to use is a Z-06 diff cooler setup with the A-6 ratio's. There is a kit for adding a mechanical external pump to the diff but it costs somewhere in the neighborhood of 1200 to have someone do the install bringing the total package to 3k - the approximate cost of a replacement differential.
Would love to hear any additional thoughts...
Thread Starter
Instructor
Joined: Apr 2013
Posts: 123
Likes: 1
From: Kinderhook NY
a diff cooler would probalby be a good idea as well for track days. I know the moser 12 bolt in my IROC gets too hot to touch within about 20 mins on the track. I installed a gauge and it routinely pegs it at 250. So the ZO6 comes stock with a diff cooler?
Race Director
Joined: Aug 2005
Posts: 13,592
Likes: 187
From: Hudson WI
NCM Sinkhole Donor
Race Director
Joined: Sep 2007
Posts: 16,557
Likes: 2,108
From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
True. The pump is in the rear cover and the lines tie into the cooler as shown. I'm not sure why the side cover would be different, but maybe it's to mount the cooler.
Race Director
Joined: Aug 2005
Posts: 13,592
Likes: 187
From: Hudson WI
NCM Sinkhole Donor
Ring gear needs to be cut to drive the pump.
New side cover to accept cooler
Lines to the trans cooler lines
Line fabrication because the Z06/ZR1 lines don't line up.
That being said, I now have a diff with the cooler, Quaife Center, 3:73 gears, hardened shafts, HD pinion bearing and the stock one on the shelf so when I break it, I have a spare!
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Race Director
Joined: Aug 2005
Posts: 13,592
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From: Hudson WI
NCM Sinkhole Donor
http://quaife.co.uk/differentials
Race Director
Joined: Mar 2005
Posts: 10,399
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From: Austin Texas
Quaife differential also has the benefit of being able to use lubricants that can't be used in a clutch type diff. That's one reason many FWD cars use a Torsen style differentials in their transaxles. One fluid for trans and diff. A requirement since the tranny and diff are in the same case and have to share lubrication.