Normal Operating Temperatures

[taquilatab]

I traded in my 2008 F250 with the 6.4 for a 2012 F350 with the 6.7. I noticed on this truck the transmission is running around 190-195 degrees with an engine temp of around 200-205. On the F250 I usually ran an engine temp of around 200 but the tranny was rarely over 170 degrees.

What is considered the normal operating temperature for this new transmission? Thanks.

[richc22a]

From FORD;
Warmer operating temperature: Tied in with spin losses, the 6R140 cooling system has been optimized to allow for the proper amount of cooling when towing heavy loads in high ambient temperatures, while running at an overall higher stabilized temperature. This higher stabilized temperature lowers the viscosity and helps the fluid flow more easily, which reduces parasitic losses and saves fuel. The fluid also warms up faster because it does not flow to the cooling circuit until properly warmed up. Faster warm-up also reduces overall parasitic losses.
– Customer fuel economy benefit: Fewer parasitic losses due to reduced fluid viscosity translates to less internal drag on the system and increases fuel economy.