Road Trip-40' Discovery 7% Grades

[brian-nicola]

Morning,

All serviced for the season and heading to the Interior. 200 miles of 7% grades in 85-90 F heat. Other than the usual up the grade gear=down the grade gear, engine brake on, keep the rpm's up 1800-2000, slow and steady wins the race any other tips?

Lots of experience pulling 5th wheels and gasser's, but this will be first trip long run in our DP. She has the ISC 380HP Cummins and Allison 6spd
Rgds/Brian

[BFlinn181]

Pay more attention to the RPMs and Temp gauge than the MPH. Keep it in the power band for your engine. Only use brakes for stopping, not slowing, the engine brake should be for slowing. If you do need the brakes, apply firmly for a 10 mph speed drop, then foot off the pedal until next need. Sounds like you know what's up, enjoy your trip.

Curious, what route are you taking that has 200 miles of 7% grades?

[DegoRed]

Don't freak out at the engine temps, they will run high, or at least they do for me. The engines in our coaches seem to like to run hot. Mine typically runs in the 215 deg range when pulling grades, then immediately cools down to 175 once over the hill. At first I was worried, but after running a lot of grades now, have learned what the norm is for my coach.

[brian-nicola]

Morning Bob,

Thanks! It is Hwy 3, the "Crows Nest Pass", grades up to 7% The worst part is from Manning Park to Princeton, then down into Keremeos.

The Crowsnest Highway's total length in British Columbia is 837 km (520 mi),[citation needed] and its total length within Alberta is 324 km (201 mi).[2] The Crowsnest Highway's western terminus is at Hope, where it branches off from Highway 1. The highway goes east for 7 km (4.3 mi) to its junction with Highway 5, then through Allison Pass and Manning Provincial Park for 127 km (79 mi) towards the Town of Princeton. There are several significant ascents in this stretch between Hope and Princeton. The first is the steep climb to the Hope Slide, followed later by the remainder of the climb up to Allison Pass at an elevation of 1,342m (4,473 ft). After the summit of Allison Pass, where the Crowsnest crosses from the Fraser Valley Regional District into the Regional District of Okanagan-Similkameen, the road descends for 40 km (25 mi) before beginning another long climb up Sunday Summit (1,284m, 4,280 ft). Soon after Sunday Summit is the descent into Princeton, where Highway 5A begins.


Through the Similkameen Valley westwards into the mountains
After Princeton, the Crowsnest goes southeast for 67 km (42 mi), through Hedley, to the Village of Keremeos, where a junction with a length of highway designated as 3A is located, leading towards Penticton and Highway 97. Another 46 km (29 mi) southeast, and the Crowsnest reaches the Town of Osoyoos and a junction with Highway 97. The highway then proceeds to hug the Canada-U.S. border east through a stretch of switchbacks known as Anarchist Mountain, which is also the name of the upland rural community beyond the summit. A few kilometres east of Anarchist Mountain, the Crowsnest enters the Regional District of Kootenay Boundary.

52 km (32 mi) east of Osoyoos, the Crowsnest reaches its junction with Highway 33 at Rock Creek, then the highway heads east for 70 km (43 mi) to its junction with Highway 41 at a location called Carson, just west of Grand Forks. Another 26 km (16 mi) east, passing through Grand Forks en route, the Crowsnest meets Highway 395 at the southern end of Christina Lake.

[Coma]

Originally Posted by BFlinn181

Pay more attention to the RPMs and Temp gauge than the MPH. Keep it in the power band for your engine. Only use brakes for stopping, not slowing, the engine brake should be for slowing. If you do need the brakes, apply firmly for a 10 mph speed drop, then foot off the pedal until next need. Sounds like you know what's up, enjoy your trip.

Curious, what route are you taking that has 200 miles of 7% grades?

Exactly.

Since you are staying under 5k ft in altitude you should have few issues. I also suggest you don't run at full boost, give yourself 3-4 lbs off of max when on the long pulls. Enjoy!

[dennis45]

Just came up the Creston Salmo pass heading East yesterday. This is a Long 8% grade. I was down to 2nd gear at about 50km/hr to maintain 210-215 temps. It was around 85-90 deg F ambient. I have read it is the longest, steepest pass in NA, not sure if that's true but it is long and steep for sure.

[96 Wideglide]

I believe it!
Did it once in my previous gas coach and when I reached the pullout at the top, my tranny was at 244* according to the scanguage!
This was in mild temps, and towing nothing!

[96 Wideglide]

That was the hill that convinced me to buy an aux electric fan for the trans cooler, but I traded the gasser for a DP before I got around to installing it.

[ShapeShifter]

Originally Posted by BFlinn181

Only use brakes for stopping, not slowing, the engine brake should be for slowing. If you do need the brakes, apply firmly for a 10 mph speed drop, then foot off the pedal until next need.

And if you need to do the next one of these "stabs" soon after the last one, you're going too fast and are in too high of a gear. You need to slow down and let the transmission downshift to get better exhaust braking effort, but that will be difficult to do at that point.

Better to start out the descent too slow and in too low of a gear and speed up if needed, because it's real hard to slow down if you're going too fast and are in too high of a gear.

Originally Posted by brian-nicola

slow and steady wins the race

Perfect attitude!