I've been eyeing the Thermal Control system and looking at my 09,,,
Unlike my prior GM's, the tranny cooler is not 'inside' the radiator, but a seperate item outside/in front of the Rad,,,
The GM's had/have a tranny cooler inside the rad to cool and warm
up the oil. Later units had a small 'external' cooler added in line with the 'internal' system.
RAM goes about it a bit differently (at least in the 4th Gens), as there is (up until now) no control over the Trans temp other than 'wide open / max cooling' by the large, independent cooler in front of the Rad. Folks up north would never see their tranny's reach 'warm' temp in winter,,, ever.
I experimented with covering the trans cooler in my 09 on a Xmas trip to Iowa. Just below freezing, with 80-85% of the tranny cooler covered, and I still didn't reach 170 on the freeway. (Ram claims optimum efficiency at 190 degrees) Even with ~1/2~ of it covered with temps in the low 50's, it wouldn't reach 170,,,
On that trip, I was able to easily monitor the trans temp for a couple days. Now that I am back home, with occaisional 80 degree days and 'short daily drives' into work each day, I run 100% uncovered cooler, but i can't honestly say I've monitered the temps much since then. (Generally gets up past 140ish,,, eventually,,,,)
Would / WILL
be NICE to have a system that does all the temp control for you!!!!!
More about the 8 spd:
The ZF eight-speed automatic is made in several different forms, including an AWD version and a version with a built in DynaStart electric motor, with 20 horsepower (15 kW) of power, making it into a parallel-hybrid transmission. The key advantages of the transmission are not so much the eight speeds (which help to keep the engine in its optimal range, and reduces the number of tradeoffs required in tuning), but the high efficiency — a claimed 98% efficiency in any gear,
with an extremely rapid locking torque converter — and high speed, with shifting taking place faster than a person can perceive it.
Original is at 845RE / 8R70: ZF 8-Speed Automatic Transmission for Chrysler cars http://www.allpar.com/mopar/transmis...#ixzz2KppYrmiD
Follow us: @allparcom on Twitter | allparcom on Facebook