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First time towing over steep grades (Saluda NC). Just want to make sure I do it correctly. Obviously I will be using T/H function. Just wandering if I need to manually drop down to 3 or stay in D when approaching the "steepness"?? Or can I stay in D, and let the AT do it's thing? Total weight is no more than 8k lbs. Thanks in advance!!


Yeah 8k is nothing for your truck. Stick it in drive with T/H on and let itrip. I live in NC and tow 10-16k tag along through mountains with no issues. Since you don’t have exhaust breaking just make sure you have good functioning dual braking trailer axles and your all set no problem.


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Ignore the bullshit. I've pulled my relatively small trailer (about 10k) back and forth across the continent and there are plenty of little "ant hills" here in NJ/NY (try route 23 up by High Point, NJ or 23A east of Tannersville, NY) that are just as challenging to descend safely as the big mountains out west.

And if I recall correctly, you're in NC...I doubt anyone would call Mount Mitchell an ant hill. ;)
Have you camped in Acra, NY? Off of Rte. 23 heading towards Windham, Hunter, Tannersville. That's near my old stomping ground. Used to motorcycle ride all through there. I'll be up there in two weeks.
 

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Discussion Starter #24
And if I recall correctly, you're in NC...I doubt anyone would call Mount Mitchell an ant hill. <img src="http://www.duramaxforum.com/forum/images/smilies/wink.gif" border="0" alt="" title="Wink" class="inlineimg" />
Yea man plenty steep for me! Google Saluda Grade if you get a chance. Pretty cool piece of history we have here in NC.
 

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Have you camped in Acra, NY? Off of Rte. 23 heading towards Windham, Hunter, Tannersville. That's near my old stomping ground. Used to motorcycle ride all through there. I'll be up there in two weeks.
I haven't camped there but I've stayed up that way at a few different BnBs. Great area. If you're going to be there on Sunday 11 August shoot me a PM. I'll be heading back to the NYC area from Geneva (by Seneca Lake) and Acra is not far out of the way. I've been known to carry beer in my truck...
 

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No worries mon! My LLY has spent a LOT of time pulling in Colorado, many passes over 12K and 7%+. Million Dollar Highway, the Ike, Hoosier pass, lots of others plus our own here in the PNW. I prefer to drop down to 4 manually by locking out od before I start pulling a grade. Yes the Ally will downshift, but I don't like to let it hunt back and forth between 4 & 5, it's hard on clutches. Just watch EGTs, use T/H and keep RPM in the sweet range as others have advised. And don't try to beat everyone else up the hill....
 
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1800-2000 is a better rpm range on flat ground all your temps will be happier.
I prefer around 2100 on flat ground 5th gear never 6th gear, lock out 6th by selecting manual and 5th
Manual down when needed manual up when needed.
If you had a EGT gauge then you’d see exactly why you really never want to have lower rpms than what I mentioned above.

Even with towhaul selected the trans will not shift into 6th at 65 mph.
Take it up to 70+ mph then you’ll see it’ll shift into 6th with towhaul engaged, this is just not all that wise towing in 6th gear, your lugging the engine below 1800 towing on flat ground.

Pulling grades rpms 2200-2500 pulling grades
good, for short time 2600- 2700 if needed not consistently, 2800 - 3000 only for short burst if needed, keep the speed down a little you won’t need to utilize the short burst.

Listen closely to your engine and rpms with the different rpms, watch your temps, if you don’t have a EGT gauge pre-turbo consider installing one.
Post turbo I’ve found there will be 300-500 degree difference pulling a grade being pre-turbo is much hotter.
I use to monitor EGT’s pre and post turbo at the same time, same truck, same engine.
 
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I wish I could remember the rd but it’s like hwy 23 or one connecting to it that comes out of western North Carolina into GA toward Blairsville I think. Near the Chattahoochee national forest. Not sure the grade but both my 08 Powerstroke and trailer brakes were very hot after a steep grade. Actually had to totally rebuild both front sets on truck as they got destroyed on way down. Was a white knuckle experience for sure. When I got back to Black Mountain which is a 6% grade it seemed pretty easy compared to the previous mentioned mountain. Except for knowing my front brakes were in bad shape. Lol

Now that I have my new truck though black Mountain is a piece of cake. Total trailer weight with tractor was just over 15k and hardly ever touched the brakes coming down this 6% grade. The Allison plus exhaust breaking were awesome. The last picture is the truck using tranny and engine braking to hold back the load coming down Black Mountain. I seriously only tapped the brake pedal maybe 4-5 times and a couple times applied some fuel as I was slowed to much.


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I haven't camped there but I've stayed up that way at a few different BnBs. Great area. If you're going to be there on Sunday 11 August shoot me a PM. I'll be heading back to the NYC area from Geneva (by Seneca Lake) and Acra is not far out of the way. I've been known to carry beer in my truck...
Flying out of Florida Aug. 13th and returning Aug. 21st. Got a decent deal on Southwest. PBI to ALB $250 round trip. I can't get there one way with fuel/tolls for that. Maybe next time. Thanks!
 
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Flying out of Florida Aug. 13th and returning Aug. 21st. Got a decent deal on Southwest. PBI to ALB $250 round trip. I can't get there one way with fuel/tolls for that. Maybe next time. Thanks!
Impressive. Is that a direct flight?
 

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Discussion Starter #31
No worries mon! My LLY has spent a LOT of time pulling in Colorado, many passes over 12K and 7%+. Million Dollar Highway, the Ike, Hoosier pass, lots of others plus our own here in the PNW. I prefer to drop down to 4 manually by locking out od before I start pulling a grade. Yes the Ally will downshift, but I don't like to let it hunt back and forth between 4 & 5, it's hard on clutches. Just watch EGTs, use T/H and keep RPM in the sweet range as others have advised. And don't try to beat everyone else up the hill....
Right on man. What’s the egt danger zone? I was hanging around 1200-1230 a couple times. Thanks!
 

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Discussion Starter #32
1800-2000 is a better rpm range on flat ground all your temps will be happier.
I prefer around 2100 on flat ground 5th gear never 6th gear, lock out 6th by selecting manual and 5th
Manual down when needed manual up when needed.
If you had a EGT gauge then you’d see exactly why you really never want to have lower rpms than what I mentioned above.

Even with towhaul selected the trans will not shift into 6th at 65 mph.
Take it up to 70+ mph then you’ll see it’ll shift into 6th with towhaul engaged, this is just not all that wise towing in 6th gear, your lugging the engine below 1800 towing on flat ground.

Pulling grades rpms 2200-2500 pulling grades
good, for short time 2600- 2700 if needed not consistently, 2800 - 3000 only for short burst if needed, keep the speed down a little you won’t need to utilize the short burst.

Listen closely to your engine and rpms with the different rpms, watch your temps, if you don’t have a EGT gauge pre-turbo consider installing one.
Post turbo I’ve found there will be 300-500 degree difference pulling a grade being pre-turbo is much hotter.
I use to monitor EGT’s pre and post turbo at the same time, same truck, same engine.
My 05 is a 5 speed but I get what ur saying. I do have EGT gauge post turbo. Thanks for the rpm ranges
 

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I wish I could remember the rd but it’s like hwy 23 or one connecting to it that comes out of western North Carolina into GA toward Blairsville I think. Near the Chattahoochee national forest. Not sure the grade but both my 08 Powerstroke and trailer brakes were very hot after a steep grade. Actually had to totally rebuild both front sets on truck as they got destroyed on way down. Was a white knuckle experience for sure. When I got back to Black Mountain which is a 6% grade it seemed pretty easy compared to the previous mentioned mountain. Except for knowing my front brakes were in bad shape. Lol

Now that I have my new truck though black Mountain is a piece of cake. Total trailer weight with tractor was just over 15k and hardly ever touched the brakes coming down this 6% grade. The Allison plus exhaust breaking were awesome. The last picture is the truck using tranny and engine braking to hold back the load coming down Black Mountain. I seriously only tapped the brake pedal maybe 4-5 times and a couple times applied some fuel as I was slowed to much.


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Good lookin setup man.
 

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My 05 is a 5 speed but I get what ur saying. I do have EGT gauge post turbo. Thanks for the rpm ranges
Have to be careful with post turbo, if your not tuned you might be ok.

This was mentioned on another post.
On using towhaul it’s hard on the trans clutches if you engage and dis-engage under load.
Allison will tell you this.
Dis-engaging is not as hard but engaging TH under load with the rpm changes is hard on them.

EGT’s
Right on man. What’s the egt danger zone? I was hanging around 1200-1230 a couple times. Thanks!
1200-1230 is safe.
I have my CTS2 EGT alert set at 1350, but I try to stay around 1150-1200.

Some will say you can sustain 1300-1400, I wouldn’t ever suggest this.
 
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My 05 is a 5 speed but I get what ur saying. I do have EGT gauge post turbo. Thanks for the rpm ranges
Have to be careful with post turbo, if your not tuned you might be ok.

This was mentioned on another post.
On using towhaul it’s hard on the trans clutches if you engage and dis-engage under load.
Allison will tell you this.
Dis-engaging is not as hard but engaging TH under load with the rpm changes is hard on them.

EGT’s
Right on man. What’s the egt danger zone? I was hanging around 1200-1230 a couple times. Thanks!
1200-1230 is safe.
I have my CTS2 EGT alert set at 1350, but I try to stay around 1150-1200.

Some will say you can sustain 1300-1400, I wouldn’t ever suggest this.
Good stuff. Thanks!
 

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I wish I could remember the rd but it’s like hwy 23 or one connecting to it that comes out of western North Carolina into GA toward Blairsville I think. Near the Chattahoochee national forest. Not sure the grade but both my 08 Powerstroke and trailer brakes were very hot after a steep grade. Actually had to totally rebuild both front sets on truck as they got destroyed on way down. Was a white knuckle experience for sure. When I got back to Black Mountain which is a 6% grade it seemed pretty easy compared to the previous mentioned mountain. Except for knowing my front brakes were in bad shape. Lol

Now that I have my new truck though black Mountain is a piece of cake. Total trailer weight with tractor was just over 15k and hardly ever touched the brakes coming down this 6% grade. The Allison plus exhaust breaking were awesome. The last picture is the truck using tranny and engine braking to hold back the load coming down Black Mountain. I seriously only tapped the brake pedal maybe 4-5 times and a couple times applied some fuel as I was slowed to much.


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For a tractor that size you really ought to think about chains and binders instead of straps.
 

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Allison will tell you this.
You've mentioned this in the past...you recall reading it somewhere, but can't recall where.

I have to disagree.
Allison made the 1000 idiot proof. You can make a request via the shifter, but if the TCM doesn't like your suggestion, it ain't going to happen.

Just like trying to 'request' R while going forward (DIC states 'Idiot!' or something like that), there is logic in the tuning to handle T/H switch while doing, whatever.

It won't let it be a slamming move, it'll calm things down and change things at the pace it wants. Now I'm sure there are limits....like sitting there continually tapping the button, etc.

Remember, the natural state of how it's built to operate is to always be in T/H mode.
The HD just has a button to disengage/calm and please the mall crawlin' crowd.

It'd be perfectly happy if you'd just leave it be, with the trailer icon light on, whether you're towing or not.
That's it's natural state of design. :thumb
 
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Stop by any actual Allison service department they’ll tell you exactly what I’ve been saying.
Allison suggests when you tow engage towhaul and leave it engaged until your done towing, you’ve even said this, so what’s your problem.
Better yet maybe one of the members that has a local Williams Allison near by to prove your just spouting off as usual.
This was a Allison FAQ that I posted several years ago, some new breed youngster computer master for Allison decided to remove this FAQ,
Any Allison tech will tell you that he’d wish they would put that FAQ back up, it was very helpful for customers.

I haven t forgotten anything, it’s you that won’t give up on you bs.
I don’t think you need anymore post but you sure like to stir something up to be noticed once again.
Sure the Allison is suppose to be idiot proof but not dum ass proof.
I remember somewhere along the way over the years you mentioning it is hard on the trans engaging towhaul under heavy load towing.
Apparently you’ve forgotten mentioning this.

I don’t understand your reasoning to continue with crap when someone is just offering advice, that would be easier on the trans.
 

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Well these here ant hills are steep enough for me and my 2500 so that’s why I reached out for advice. No matter one’s terrain or situation, it’s great to be part of a forum that’s willing to jump in and help a dude out. So, even though you live close to the “real hills”, I appreciate your advice on how to navigate our little bumps in the road.
Alright, alright. I apologize.
 

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I wish I could remember the rd but it’s like hwy 23 or one connecting to it that comes out of western North Carolina into GA toward Blairsville I think. Near the Chattahoochee national forest. Not sure the grade but both my 08 Powerstroke and trailer brakes were very hot after a steep grade. Actually had to totally rebuild both front sets on truck as they got destroyed on way down. Was a white knuckle experience for sure. When I got back to Black Mountain which is a 6% grade it seemed pretty easy compared to the previous mentioned mountain. Except for knowing my front brakes were in bad shape. Lol

Now that I have my new truck though black Mountain is a piece of cake. Total trailer weight with tractor was just over 15k and hardly ever touched the brakes coming down this 6% grade. The Allison plus exhaust breaking were awesome. The last picture is the truck using tranny and engine braking to hold back the load coming down Black Mountain. I seriously only tapped the brake pedal maybe 4-5 times and a couple times applied some fuel as I was slowed to much.


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Not sure but you are most likely talking about 64. Comes out of Franklin nc towards hiawassee ga. It's about an 8% grade for the first few miles.

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