Some years ago, there was a forum thread discussing what transmission gear did folks drive. My forum search skills are quite substandard and finds nothing. If someone who is more familiar with how the search tool works and can provide a link, I'd appreciate it.
Larry
The trick to searching with the Forum Search Tool is selecting the proper "key words". This takes practice, and much "trial & error".
I searched for "manual gear selection". Got a whole page of hits.
See if any of these threads look like what you want:
Downhill Speed Control - Proper Gear Selection vs Retarder (https://www.foreforums.com/index.php?topic=34029)
Manual Shifting Allison (https://www.foreforums.com/index.php?topic=30897)
Got my Allison "Mode On" (https://www.foreforums.com/index.php?topic=37027)
ISM450 Fuel Mileage (https://www.foreforums.com/index.php?topic=29320)
OZARK MOUNTAINS, MEDIUM RAIN, NO RETARDER -- FIRST TIMER (https://www.foreforums.com/index.php?topic=8203)
Thank you U295 for RTFM!
But, that never stopped my from adding my own 2¢ worth based on my experience over some time spent driving everything from antique automobiles to several decades of motorhomes.
I have the Cummins 5.9, Allison 4-speed and drum brakes. All up weight is 22,500 pounds.
1) "D" and I drive it like my 1950 Chrysler with the Prestomatic Tip Toe Shift and Gyrol Fluid Drive. I grab about 2/3s throttle, sit back and wait as I "Soar Away in a Smooth Crescendo of Power."
2) Uphill on a long grade, 3, 2, and even 1. Whatever it takes to keep my foot off the firewall. Running flat out for long periods of time the water gets hot and so does the oil, lowering the oil pressure. A remote camera on your turbocharger might give you that little push to drive slower up hill once you see the glow.
3) Downhill? Everything from both feet flat on the floor shouting Wheeeee ! to starting at the top in 1st gear from a dead stop. A 30,000 pound motorhome carries a lot of potential energy to be dissipated on the way down a long steep grade. Once the brakes get too hot to work effectively, you're out of options.
Just my 2¢ worth on a quiet Saturday morning.
Thanks, guys, for being so helpful. I appreciate it.
Larry
As I get older it's sometimes requires reading things more than one time for my "light to go on". In rereading Brett Wolfe's article on transmission mode I finally saw and understood:
"Every time you start the motorhome, the transmission is in Performance Mode. This is the default setting. If you push the mode button, it goes to Economy Mode and the light illuminates."
I had been thinking the opposite.
My understanding is that it varies with different models. For example, on our 1995 U320 with Cummins M11 and the Allison 4000 series transmission the default is as you describe above, but I've read that on others it's just the opposite.
Customer selectable at a Allison shop