Drdgsanta Report post Posted July 18, 2018 I have a 2011 Winnebago Tour and flat tow a Jeep Wrangler. I do not know the automatic shifting protocols when climbing steep grades. Looking for some advice before my next trip. Thanks in advance! Share this post Link to post Share on other sites
wildebill308 Report post Posted July 19, 2018 Welcome to the forum. I would find out what your 2 most important RPMs are peak torque and max governed RPM. When climbing you want to stay at or above peak torque and under your Max governed speed. When you are climbing you want to be in a gear you can accelerate in. Said anouther way if you can't accelerate or hold speed you need to downshift till you can. You may not be the first to the top but you will make it just fine. I have often had more problems with slower traffic on hills where you can't get around them safely. Then you just have to slow down and enjoy the view. I doubt you will be able to tell you are towing so that shouldn't be a factor. Bill Share this post Link to post Share on other sites
Drdgsanta Report post Posted July 19, 2018 Bill, Thanks for the information. What is the best way to down shift. I have a push button panel and I’m not sure when and how to downshift. Share this post Link to post Share on other sites
manholt Report post Posted July 19, 2018 If your in 6 gear, and your speed/rpm start drooping then touch the down arrow on your Allison pad. you go to 5 first, then touch again for 4. etc. the opposite for a low gear to a higher gear! Works both in Cruise Control and no CC. Share this post Link to post Share on other sites
wildebill308 Report post Posted July 19, 2018 Like Carl said, just remember to shift up once you get to the top of the hill or the grade improves where you can pull/accelerate in a higher gear. You want to go back to 6th gear(selected) at the top. Next timeout try experimenting a little, you will get the hang of it easy enough. Bill Share this post Link to post Share on other sites
Drdgsanta Report post Posted July 19, 2018 Thanks! I appreciate the responses and look forward to joining the RV community. Safe travels! Share this post Link to post Share on other sites
fagnaml Report post Posted July 19, 2018 Carl, Bill -- I'll give a different perspective and then have you share your thoughts for the group. My 2007 motorhome has a 300 HP Cummins ISB with the Allison MH-2500 five speed transmission. When climbing hills in the Texas Hill Country. For example the climb to La Hacienda RV Resort on Lake Travis northwest of Austin is rather substantial especially by the dam and the climb out of Marble Falls is quite step and has a stop light in the middle of the climb! From my perspective my transmission downshifts about the time I think it should thus I have not had the need to manually downshift. I've also had no problems climbing the steep bridges over rivers along I-10 in Louisiana. I typically average 50 mph going up those steep inclines be then a big I-10 bridge or a longer steep hill in the Hill Country. Steep climbs in the Rockies or other mountainous roads may be a different story. Share this post Link to post Share on other sites
elkhartjim Report post Posted July 19, 2018 Those are all relatively short climbs albeit they are a little steep. Carl and I are very familiar with the hill in Marble Falls. You just need to stop at the Bluebonnet Cafe during pie happy hour to make the climb easier. Share this post Link to post Share on other sites
wayne77590 Report post Posted July 20, 2018 I have a different approach. I watch the engine temperature gauge, When it starts to get higher than 207˚RR I'll down shift until I can get the RPMs to 2000-2500 RPM. I may have to reduce speed also. I'll notice a drop in temperature almost immediately. You have a 450Hp Diesel pushing you along so you should not have a problem, just keep your engine happy. Share this post Link to post Share on other sites
manholt Report post Posted July 20, 2018 Mike.The equation is. Weight, drag, available HP and transmission. Then you have to add in Ambient temperature....I have no problem in 4th or 5th gear, my torque is 1250 at 2300 rpm (4th) and 2150 (5th)! Long 6% grades from 6000 feet to 11,000 feet is another problem, like I-70 in Colorado! Share this post Link to post Share on other sites
wildebill308 Report post Posted July 20, 2018 While it is important to monitor engine temps. I keep a close eye on EGT temps as they can rise much quicker than engine temps. You hear about the super hills the super steep ones but I have seen over temp on long gradual climbs. My first experience was going from the Grand Canyon toward Vagus. I was running on cruise and all of a sudden had warnings for high engine temp. While I was able to maintain speed in 6th gear on cruise the computer was all in trying to maintain that speed. It was like you were driving with your foot flat on the floor to maintain speed. I slowed a little manually shifted down to 4th and the temps started to drop. When they were acceptable I tried 5th and drove the rest of that section in 5th. This is to show not all over temp problems happen on super steep hills. Bill Share this post Link to post Share on other sites
wolfe10 Report post Posted July 20, 2018 If the engine is still to OE spec (not been hot-rodded) AND you select a gear where you can still (barely) accelerate, EGT's should not be a problem. Yes, WOT, particularly in hot summer temps can push the envelope. Share this post Link to post Share on other sites
