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View Full Version : Tow Haul Mode Downshifting Hard



whiteelephant
09-04-2007, 04:18 PM
Has anyone noticed when in Tow Haul mode, if you slow down by applying the brake, it causes a hard downshift to occur? This causes the brake controller to apply the trailer brakes too much (suddenly) resulting in jolt or tug.:eek:

Do other trucks that have the tow haul mode feature (i.e. chevy) have this issue with hard downshifting?

Suggestions, recommendations would be appreciated.

I'm using the Tekonsha Prodigy V.2 brake controller.

RugRat
09-04-2007, 04:52 PM
I have the tow/haul mode on my ford and the prodigy brake controller and no problems with hard downshifts or trailer brakes being applied when the truck downshifts due to tow/haul mode.

jpmorgan37
09-04-2007, 06:04 PM
I had the tow/haul mode on my last GMC and Chevy before that. I never experienced any harsh downshift. I had several different brake controllers before I switched to the Brake Smart, but didn't have the condition that you are describing.

John

whiteelephant
09-04-2007, 08:36 PM
Thanks for the info. I guess I'll have to re-learn how to slow down without using the brakes. My truck has the factory jake brake. I never tried using it while in tow haul mode.

Uncle Rog
09-04-2007, 09:02 PM
When using the Allison going down hill the brakes are not engaged, and if I am trying to slow down a lot the tranny does grab pretty hard. If I am in a pretty controlled descent the shifting is very smooth. Last August coming down the grapevine above LA I locked her in at 55 and the tranny held her steady for 30 miles, never even touched the brakes......

trdeal
09-05-2007, 08:34 AM
Maybe you need to back off the brake control a little to keep the trailer brakes from grabbing.I have a 2007 Ford with the tourque shift and built in brake control and have not had any problems.

whiteelephant
09-05-2007, 12:21 PM
trdeal,
I'll try that and see if there is any improvement. This morning while going to work and with no trailer, I decided to run Tow Haul Mode. You can sure feel the downshifting when slowing down. Kind'a scary on wet pavement.

Pulltab
09-05-2007, 02:36 PM
The downshift without weight on the trailer is definetly strong. My dodge does the same thing, with weight it is much better. If your break control has an adjustment for when the brakes take hold you might try adjusting that. It is basically a sensitivity control that you can set from immediate application to a short delay before the electric brakes apply. Other than that do like the others said and back off the setting on the brakes so they don't grab so hard.

What happens is when the exhaust brake is on and the tow haul mode engaged as soon as you tap the brakes the computer takes over trying to keep the rpm's high enough to make the exhaust brake effective. And it works WELL! Never had a truck that it worked so well on. Going down 6% grades in West Virginia a couple of weeks ago I had to actually apply throttle to pick up speed going DOWN hill. :) I like that!

whiteelephant
09-05-2007, 02:49 PM
Thank everyone. I'll try the suggestions mentioned above.

trdeal
09-06-2007, 05:50 AM
trdeal,
I'll try that and see if there is any improvement. This morning while going to work and with no trailer, I decided to run Tow Haul Mode. You can sure feel the downshifting when slowing down. Kind'a scary on wet pavement.The Ford owners manual reccomends that you do not use the tow/haul mode on wet pavement because of possibly losing traction. Last weekend we were towing on wet pavement and did not use tow/haul. I like the tow/haul because of the engine braking. There has been a few times when I was cut off or had to get on the brakes while towing and glad we had the extra stopping power.

TrickyD
09-12-2007, 01:48 AM
TRdeal, I tow a 2008 3055RL with a 2008 F350 diesel. It also has the factory brake controller. What setting do you normally use? I've tried 2.5 to 3.5 range and don't really notice any difference, however I try to use the brakes as little as possible and prefer to let the engine slow me down. If the breakaway cable has been detached would this affect the braking? (Second time I unhooked I forgot the breakaway cable, Bighorn was in Manitoba, and cable was in Alberta lol)I reconnected it, but often wonder if the trailer brakes are working. I think the best way to check would be on a gravel road and keep adjusting until one feels and hears the trailer brakes grab, then back it off a notch. This worked well with my old pull behind trailer. Does the same strategy apply to fifth wheels?

TrickyD

trdeal
09-12-2007, 04:53 AM
TRdeal, I tow a 2008 3055RL with a 2008 F350 diesel. It also has the factory brake controller. What setting do you normally use? I've tried 2.5 to 3.5 range and don't really notice any difference, however I try to use the brakes as little as possible and prefer to let the engine slow me down. If the breakaway cable has been detached would this affect the braking? (Second time I unhooked I forgot the breakaway cable, Bighorn was in Manitoba, and cable was in Alberta lol)I reconnected it, but often wonder if the trailer brakes are working. I think the best way to check would be on a gravel road and keep adjusting until one feels and hears the trailer brakes grab, then back it off a notch. This worked well with my old pull behind trailer. Does the same strategy apply to fifth wheels?

TrickyDI use the 7.0 setting on my control and I adjusted it just like I did when I owned a travel trailer.Not on a gravel road, but on pavement. You don't want the brakes to lock up and I think you will get a better adjustment on pavement. I like you let the engine do the braking. The camper stops smoothly behind me without any brake grabbing. I really enjoy the way the engine slows you. I have been in situations(you know how you are treated on the road if you are towing)when I was glad I had the extra braking power. As far as the breakaway cable goes it only affects your brakes when the cable is pulled. This is supposed to apply the brakes on your unit if the truck and camper become disconnected on the road. I assume that once the camper is at a standstill the switch resets, but you know what they say when you assume something. I am sure that others will weigh in on this question as well. Hope this helps.

v92c
09-12-2007, 01:10 PM
I am sure this will raise some contraversy, but I dont like the Tow/Haul mode. And dont use it under normal conditions, like everyday towing. I will use it on dry road, when descending from the mountains. But my Dodge pulls like a bull and doesnt need the extra torque from "over reving the engine"

Tony

Forrest Fetherolf
09-12-2007, 02:45 PM
[quote=v92c]I am sure this will raise some contraversy, but I dont like the Tow/Haul mode. And dont use it under normal conditions, like everyday towing. I will use it on dry road, when descending from the mountains. But my Dodge pulls like a bull and doesnt need the extra torque from "over reving the engine"

Wow!!!!!!!!!!
If you haven't, you might want to read up on the tow/haul mode. The tow/haul mode only changes the shift pattern when towing to eliminate constant upshift/down shift, and locks up the torque converter to eliminate slippage. Slippage causes excessive heat, which cause the transmission to become unhappy and fail, leaving you stranded. The tow/haul does not cause the engine to over-rev, if anything, the engine will turn a higher rpms without it due to torque converter slippage, All diesel's have plenty of power, the fragile component is the transmission.

Forrest

trdeal
09-12-2007, 03:30 PM
I think this has already been stated before but the owners manual states that you should not use tow/haul on wet pavement because of the danger of losing traction when the truck down shifts. I did tow labor day wekend on wet pavement in the normal mode and the only difference I could see was the difference in shift pattern and no engine braking when I applied the brakes. My Ford towed my Landmark just fine in the standard mode, but I want to do all I can to save my transmission so when I can I will use tow/haul.

TrickyD
09-13-2007, 12:42 PM
Thanks Terry. Nest time I hook up to the BH I'll try the higher # settings. I've also been pulling a 16' enclosed cargo trailer, with controller set at 3 and it works perfectly on that setting for that trailer. Guess I'll just have to experiment a little more with the BH. I just wish it were closer, but we are in process of moving and better to leave it where it is for the time being.
TD

trdeal
09-13-2007, 06:57 PM
Thanks Terry. Nest time I hook up to the BH I'll try the higher # settings. I've also been pulling a 16' enclosed cargo trailer, with controller set at 3 and it works perfectly on that setting for that trailer. Guess I'll just have to experiment a little more with the BH. I just wish it were closer, but we are in process of moving and better to leave it where it is for the time being.
TDGlad to help TrickyD. Be careful out there.