rjweiss

I'm planning a cross country trip this fall and I would like to know how to best use the 48RE auto for braking on those long downhill stretches we will be encountering.

Do I just press the overdrive button to knock it out of overdrive or do I actually shift down one gear using the selector lever or do both?

I'll be towing a 25' 5th wheel and don't have an exhaust brake, it's a 2003 2500 5.9L.

Any ideas?

Thanks

Ron W.

Rrloren1

When I had my '98 12valve and towed a 34ft TT out West I used both methods, that is I kicked off the OD and if needed I would downshift manually. On severe mountain grades I crested at about 50 mph and kept it there all the way downhill downshifting as needed and tapping the brakes .
I don't remember ever having any real problems, just take the severe slopes slowly and don't worry about anyone behind you. Drive safe.

KATOOM

I dont have an auto but I have read that when towing, if the torque convertor isn't locked while going downhill.....and you're using engine for braking, that the tranny temps will get hot. I have no idea how much truth there is to this nor if all circumstances would cause an issue or not. No matter, if you dont have an exhaust brake then take your time on the downgrades.

scottsjeeprolet

You'll need a transmission controller to keep the TC locked. Otherwise the TC unlocks and will not help much at all.
I just installed an ATS Co-Pilot and so far like it.

BarryG

What I have found works the best for me and my trailer is just what you described. I take it out of overdrive first. Then if that is still not enough I downshift into second. I dont usually do that unless it is fairly steep and or curvey. For example if I am going down the west side of Wolf Creek pass it is approx ten miles of downhill with some decent curves on it. When I crest the top I will drop out of overdrive and coast down the hill for the first part with an occassional bit of braking too keep the speed in check. Then it starts to get steeper and some sharper curves are coming so I brake enough to drop it into second and then coast down through that section. I dont usually need to use my brakes since I am in second. Then after the steeper curvey section is passed I put it back in drive and cost down some more then towards the bottom I will need to brake a bit as there is a decent curve at the bottom. Once past the curve I put the od back on and continue on my way. I have even used 4 low at times to control my speed and braking needs obviously on steep dirt/gravel roads to control speed as sometimes using first is even too much without a lot of braking.

Right or wrong I personally dont ride my brakes down the hill, If I need to brake I tend to brake harder to get me below the speed I want then coast back up to speed then a bit over then brake harder to get back below my wanted speed etc. I have found for me that seems to reduce brake fade in those types of circumstances and if that is happening too much or should say too quickly then I downshift into second.
I have never noticed my trans temp getting warmer on the contrary I see it drop. Same with my egts after coasting down that hill for a bit they drop to under 300 and in the winter time have seen them drop below 200 on that stretch.

shep1

Don't ride your brakes! It will cause them to overheat and fadeout on you when you need them. Like the man said, get on them good to lower you're speed then get off them and let them cool down. Not sure about tranny temps in lower gears, but speed control on long steep down hills is a must. I love my exhaust brake towing in the mountains.