Second Chance Posted April 16, 2017 Report Share Posted April 16, 2017 We are planning our route back east from southern California and want to see as much of Route 66 as possible. Checking things out on flattestroute.com, it shows a 16% grade on I-40 on the southwest side of Kingman, AZ. I thought 7 - 9% was max on interstate highways... is this short stretch really 16% and, if so, should I be concerned about it with the rig in the signature? If we stick to this route, we'll probably get to Kingman this coming Friday or Saturday. Thanks, Rob 2012 F350 CC LB DRW 6.7 2020 Solitude 310GK-R, MORryde IS, disc brakes, solar, DP windows Full-time since 8/2015 Link to comment Share on other sites More sharing options...
mptjelgin Posted April 17, 2017 Report Share Posted April 17, 2017 I believe you are correct that the steepest grade on an Interstate is about 7%. That is the steepest that we have encountered and we've been through most of the mountain states and over many of the "notable" passes. Even on a US Hwy I doubt you'd find anything approaching even 10%, let alone 16%. Mark & Teri 2021 Grand Designs Imagine 2500RL, 2019 Ford F-350 Mark & Teri's Travels Link to comment Share on other sites More sharing options...
Jim Seward Posted April 17, 2017 Report Share Posted April 17, 2017 Went to this site:https://www.mountaindirectory.com/sample/arizona.html and found the following information: I-40 (near Ash Fork, AZ) About 10 miles east of Ash Fork there is a brake check area for westbound traffic (near milepost 155½ and some warning signs—"Trucks—vehicles pulling trailers check brakes and equipment—use lower gear" and "6% grade next 6 miles." The first two miles are 6% followed by about 1½ miles of 4-5%, then 1½ miles of 6% grade. We've traveled I-40 in the past and never encountered any 16% grades. Good luck and have a safe trip... Jim & Sherry Seward 2000 Residency Mod. 3790 2003 Suzuki XL/7 4WD Link to comment Share on other sites More sharing options...
Tahoe Shark Posted April 17, 2017 Report Share Posted April 17, 2017 I have driven that route from Kingman to Williams and then up to flagstaff several times with my trailer and while it is a climb 6-7% I really don't remember any thing even near that kind of grade. Tim & Cheryl 2015 Mobile Suites 39 TKSB3 2009 Volvo 670 D13 I-Shift “Walter” Happily Living Somewhere In Nevada Link to comment Share on other sites More sharing options...
Second Chance Posted April 17, 2017 Author Report Share Posted April 17, 2017 Thanks, folks. Flattestroutes.com has mislead me before and you have confirmed my suspicions. I think we'll even take the surviving stretch of the original Route 66 between Kingman and Seligman via Hackberry, etc... Rob 2012 F350 CC LB DRW 6.7 2020 Solitude 310GK-R, MORryde IS, disc brakes, solar, DP windows Full-time since 8/2015 Link to comment Share on other sites More sharing options...
WILDEBILL308 Posted April 17, 2017 Report Share Posted April 17, 2017 Drove it last summer, no problem. I have driven I-40 several times. Yes there are some hills and you might need to down shift but no big problems. We were at Williams and the Grand Canyon last mounth. We came up I-17 from Phoix. There is a good climb out of ABQ but still no big problem. If you want to stay at a place right on the old rout 66 look at this place it isn't fancy. The new owners are trying to get it fixed up and turned around. We used it when we went to The Petrified Forest National Park, nps.gov Sun Valley RV Resort, 86029, 7625 Quartzsite St, Holbrook, AZ 86025, sunvalleyrvresort.com, (928) 524-2972 Have a fun trip. Bill 2008 Newmar Mountain Aire model 4521 450 hp Cummins ISM Allison 4000MH tran. Towing a 2014 Honda CRV with a blue Ox tow bar Home base Fort Worth Texas A man who carries a cat by the tail learns something he can learn in no other way. -Mark Twain- Link to comment Share on other sites More sharing options...
2gypsies Posted April 17, 2017 Report Share Posted April 17, 2017 flattestroute.com is an very inaccurate way of looking at grades. No, I-40 or any interstate does not have a 16% grade. Full-timed for 16 YearsTraveled 8 yr in a 2004 Newmar Dutch Star 40' Motorhome and 8 yr in a 33' Travel Supreme 5th Wheel Link to comment Share on other sites More sharing options...
Second Chance Posted April 17, 2017 Author Report Share Posted April 17, 2017 18 minutes ago, 2gypsies said: flattestroute.com is an very inaccurate way of looking at grades. No, I-40 or any interstate does not have a 16% grade. So what do you suggest - ordering both the east and west Mountain Directories? Rob 2012 F350 CC LB DRW 6.7 2020 Solitude 310GK-R, MORryde IS, disc brakes, solar, DP windows Full-time since 8/2015 Link to comment Share on other sites More sharing options...
Ronbo Posted April 17, 2017 Report Share Posted April 17, 2017 I doubt if you could keep traction on 16% Ron C. 2013 Dynamax Trilogy 3850 D3 2000 Kenworth T2000 Optimus Prime Link to comment Share on other sites More sharing options...
Darryl&Rita Posted April 17, 2017 Report Share Posted April 17, 2017 58 minutes ago, Ronbo said: I doubt if you could keep traction on 16% 16% is only 16 feet of elevation change in 100 feet of horizontal travel. Assuming proper road maintenance, even gravel roads have plenty of reaction. I think I have pics of 24-26% grades on private haul roads. I have been wrong before, I'll probably be wrong again. 2000 Kenworth T 2000 w/N-14 and 10 speed Gen1 Autoshift, deck built by Star Fabrication 2006 smart fourtwo cdi cabriolet 2007 32.5' Fleetwood QuantumPlease e-mail us here. Link to comment Share on other sites More sharing options...
theeyres Posted April 17, 2017 Report Share Posted April 17, 2017 The program must have put a 1 in front of the 6 to change 6% to 16%! No problem on I-40 anywhere. 2007 Arctic Fox 32.5 rls for full-timing, now sold. 2014 Sunnybrook Sunset Creek 267rl for the local campgrounds now that we are off the road2007 Silverado 2500 diesel Loving Green Valley, AZ (just South of Tucson) Link to comment Share on other sites More sharing options...
2gypsies Posted April 17, 2017 Report Share Posted April 17, 2017 We definitely recommend the Mountain Directories and yes, if you travel in both areas they would be very helpful for you. Even though we have done the same roads over and over we always refer to the directory as a refresher course on what to expect. Full-timed for 16 YearsTraveled 8 yr in a 2004 Newmar Dutch Star 40' Motorhome and 8 yr in a 33' Travel Supreme 5th Wheel Link to comment Share on other sites More sharing options...
Second Chance Posted April 17, 2017 Author Report Share Posted April 17, 2017 Thanks, everyone. Downloading the Mountain Directory right now... Rob 2012 F350 CC LB DRW 6.7 2020 Solitude 310GK-R, MORryde IS, disc brakes, solar, DP windows Full-time since 8/2015 Link to comment Share on other sites More sharing options...
dartmouth01 Posted April 17, 2017 Report Share Posted April 17, 2017 This thread had got me thinking, what are the worst highways (interstate and state) that RVers regret going on? So I did a search and came up with a thread where everyone seemed in agreement about one particular road, 108 (Sonora Pass). 26% grades in places! I've done Kingsbury Grade into and out of Tahoe several times towing 30ft, and Tioga Pass as well, and never really felt uncomfortable with either. But I've never had the opportunity to take 108 with an RV, and it sounds like I won't be doing that anytime soon! http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/27023607/srt/pa/pging/1/page/1.cfm I found this comment to be particularly enlightening: I would never take any type of RV over Sonora Pass except a slide in camper. I have driven hwy. 550 in Colorado between Durango and Ouray and compared to Sonora Pass it's like driving on an eight lane highway.Don't do it. Link to comment Share on other sites More sharing options...
chirakawa Posted April 17, 2017 Report Share Posted April 17, 2017 9 hours ago, Ronbo said: I doubt if you could keep traction on 16% I towed across Sonora Pass which is 26% in places. It wasn't the grade which made it tough, but the narrow winding hairpin turns. Everybody wanna hear the truth, but everybody tell a lie. Everybody wanna go to Heaven, but nobody want to die. Albert King Link to comment Share on other sites More sharing options...
Tex Bigfoot Posted April 17, 2017 Report Share Posted April 17, 2017 The steepest grade on the Interstate system is on I-24/US-64 Westbound over Monteagle Mountain, TN. It's an 8% grade. Cant say for sure but I think this stretch of road has now been rebuilt and is now closer to 6% grade than 8% . I can say for sure that it was a white knuckle drive in an 1983 Freightliner and no Jake brake. Some years ago Johnny cash had a song about Monteagle . Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.