Normal Transmision Temp for 07 Z51 automatic

[Keith Pladsen]

Can anyone advise the "normal" tranny operating temp for the '07 Z51 automatic ? I saw several posts on this topic about having tranny coolers installed and my understanding is that is a built in feature on the Z51. Nothing in the owners handbook gives the "range" of normal. Thanks

[Tony B.96LT4]

Highway cruising the temps hang around 180-185 degrees. If you're doing any kind of racing they can get up to 215 and higher. Lower temps means longer life for the trans.

[C5pilot]

Keith, think of it this way... the stock cooler is located inside the coolant radiator. Coolant temps will average between 180-215. If you're not working the trans hard, it's temp should normally be in that range.

That said, before I put in my external cooler, my trans temps were hitting over 220 on a regular basis, even last winter while it was 17 outside! Nobody had any explanation for it, so I had Slapshot install a B&M cooler. (He did a real nice job too)

Now my trans temps average between 175-195 in the dead of summer no matter how hard I push it. The good part is the coolant will still heat up the trans fluid in the winter and the B&M is designed to allow colder thicker fluid to bypass most of the cooler. As the fluid thins it passes through more of the cooler. It's pretty ingenious and it doesn't rely on a bypass valve that can fail. I'll post winter temps soon enough.

[Keith Pladsen]

Thanks, that makes a lot of sense and I like the idea of a little extra protection with a secondary cooling system.

[Mike Campbell]

By the way Keith, the Z51 doesn't have a "special" tranny cooler. All A6 vettes have the same set up. It does have a power steering cooler. ;yn And, Tony's right that lower tranny temps are good!

[Keith Pladsen]

Thanks to all....very helpful.