New E450 with tow/haul question
My old Winnebago E350 4R100 had overdrive and I would turn it off when climbing a steep grade or go down a long grade for braking. What's the difference with the Tow/Haul on the 5 speed. Same usage?...
Forum Discussion
pnichols wrote:
As I understand it, the 5-speed TorqShift transmission shifts are - as controlled automaticaly - 1-2-3-5-6 in non-cold air temperatures ... and are 1-2-3-4-6 in low air temperatures.
I really don't understand the "engineering reasons" behind this duel gears ratios approach. It probably has something to do with keeping exhaust nasties below certain levels in various weather conditions. I wish all six ratios were always used - just like in the later year Ford E350/E450 transmissions.
The current six-speed transmissions use an entirely different transmission design from the older five-speed ones.
On the five speed transmission, while technically having six speeds, the two different fourth gears (4 and 5 in your list) are very close in overall ratio (1.10 and 1.00); it would be pointless to shift between them. You would go from, say, 3300 rpm to 3000 rpm on an upshift, or vice-versa on a downshift.
I think the alternate ratio is chosen when cold to improve oil circulation in the transmission or to warm the transmission fluid up more quickly or something along those lines; it has little specifically to do with engine emissions so far as I know. I also may well be mistaken in my understanding.
