Are you using the tow/haul mode too?

 

Are you trying to go down these hills with out using any brakes? When I drive 10 wheel fuel oil trucks, we used the engine to assist the braking, still needed to brake. I would use the brakes for a few seconds, let off the brakes, then the engine to keep the speed from increasing too much while I gave the brakes a chance to cool, then pressed the brakes to slow it down again and then let off…… Never had an issue doing that. I do the same with my Tundra. Worked with my 2006 DC towing a 28 ft TT. Works even better with my new Gen 3

 

Herbicidal, yes I have used tow/haul.

dtfm33, that is exactly what happens. I have been worried that the brakes might not hold on some of the longer, steeper grades. Maybe I am making a mountain out of a molehill. I expected that once in first gear, the truck would hold the speed/rpm rather than allowing both to increase. i suppose I will just resign myself to using brakes. Still, it just does not seem right.

Thank you both for responding.

 

Would putting the truck in 4x drive while going down very steep hills for say 20 miles, with a lot of switchback, be advisable? That is would the truck rpms remain constant while in first gear rather than continue to increase as it does while in 2x?

 

I have never heard of redlining in first gear as an alternative to using the brakes. You should have NO problem using your brakes to slow a 3,500 lb trailer.

 

Would putting the truck in 4x drive while going down very steep hills for say 20 miles, with a lot of switchback, be advisable? That is would the truck rpms remain constant while in first gear rather than continue to increase as it does while in 2x?

Sounds like one hell of a hill! I wouldn't advise going in 4x4 mode as on a dry road that will put a tremendous amount of stress on the front driveline.

Back to the Prodigy brake controller for a moment...is that all "dialed in" per the manufacturer's instructions? Or perhaps increase the 'boost' for this particular hill? It has a manual override, can you give the trailer additional braking while descending? Just throwing some ideas out there...

 

I have encountered a number of hills that take me to redline while in first gear. I do use the brakes on both the trailer and the truck and have not reached the point where they smoke or fade, but they do get hot.

On normal 6% or even 8% grade the truck does ok and I can usually hold my speed using third or second gear. But I like to get back into the mountains a bit. Sometimes the roads are paved, sometimes not. Grades steeper that 11% is where I am having problems.

I am just trying to find a way to not use my brakes as much.

 

I would say that accounting for the grades before you get to them and already be slowing down and in a lower gear will help. But a manual trans helps with gear selections a bit more but it can still be done.

My uncle drives a day cab 15L diesel tanker rig across the mountains and that's what he tells me is the best thing to do keep from burning the brakes. But he's got a lot of help from a 15L motor with almost 20-1 compression ratios per cylinder helping to brake but he still needs his brakes.

 

We pull a 7,500 lb TT with our 2013 DC tow package also using a prodigy 3.


In the first place, I can't believe you pulled a trailer down the back side of Deal's Gap. I thought trailers were not allowed on that stretch. We camp in that area every summer, but I would never try that.


Now back to the point. We have pulled our unit to Utah in 2014 and back to Colorado in 2015. Went down a 12% grade just north of Monument Valley and pulled up and down Monument pass which is 10 miles of 7-8% up.....and then down. And we pull to WNC at least 2x/year.


I have been in the situation you describe where the grade is so steep that 1st gear in tow mode will make the RPM's approach red line. I have been able to use the brakes cautiously and avoid any problems but like you say, I am mindful that I have only so many seconds on the brakes before they are gone. I tend to take it VERY easy down hills like that, because it is easier to maintain a steady slower speed than to try to brake down to a slower speed several times. We are 7.5 tons total and that's just too much weight to go barreling down a mountain side and expect to slow it all down at the last minute. Slow and easy.


Stay safe.