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5th yes, 6th does this include pulling grades and just towing all day in 6th.
Do you have gauges especially to monitor EGT’s ?
If not, then invest in a set then boast about towing in 6th after you see higher unsafe EGT’s.
Keeping the RPM’s up towing is a major factor for cooler temps, just chugging along in 6th, you ain’t keeping the RPM’s up above 1800-2000 on flat ground.

Yes, the Allison is smart, but when it comes to towing its slow to downshift which temps will rise until it thinks about downshifting.
Then it’s only as smart as the person behind the steering wheel.

My guess is the guy that claims he’s towing 20k all day in 6th and his trans temps are 175 he probably gets 20 mpg towing.
 
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Opinions on towing in OD? Is it a temp issue, or a torque reduction issue, and is the Allison in these trucks rated for it? Thanks.
What year are we working with? Some years there’s simple trans upgrades that could help.

The Allison is a smart transmission. No matter the weight or grade towing “D” is recommended. It will shift accordingly.

But the Driver shift control with tap up/tap down range selection for greater driver control in certain driving conditions, such as towing on a steep grade.
 

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5th yes, 6th does this include pulling grades and just towing all day in 6th.
Do you have gauges especially to monitor EGT’s ?
If not, then invest in a set then boast about towing in 6th after you see higher unsafe EGT’s.
Keeping the RPM’s up towing is a major factor for cooler temps, just chugging along in 6th, you ain’t keeping the RPM’s up above 1800-2000 on flat ground.

Yes, the Allison is smart, but when it comes to towing its slow to downshift which temps will rise until it thinks about downshifting.
Then it’s only as smart as the person behind the steering wheel.

My guess is the guy that claims he’s towing 20k all day in 6th and his trans temps are 175 he probably gets 20 mpg towing.
ill take a step back being your smarter than me. :whistle:
 

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Never found my Allison slow to shift when it is in drive with tow haul engaged.

Also never have had problems with it lugging the engine with tow haul engaged.
 

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Hi Everybody.

I hope Tom is still responding to this thread, but I have a question that I've always wondered, and there's always the internet rumors back and forth, but hearing it from the source would be nice.

Opinions on towing in OD? Is it a temp issue, or a torque reduction issue, and is the Allison in these trucks rated for it? Thanks.
From my experience it depends upon weight being towed and terrain. As long as you have tow-haul engaged you can. If you notice a lot of hunting between 5-6 then downshift manually to 5th.

Sent from my XT1097 using Tapatalk
 

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I checked Toms his activity and he was online this morning. Whether he responds or not?
 

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No hot trans here towed in 5th gear at 70 @ 2100 rpm w/4.56 gears outside temps upper 90's to 100* headed down south this pass summer trans didn't get pass 190*





 

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5th gear towing, Tats what I’m talking about :thumb:
Now let’s talk about 6th gear @ 70 mph towing, let say towing 20k the rpms would be around 1600 if your real lucky, lugging and hotter temps. :thumbsdow
Even if you picked up the speed to hit 2100, which would be around 80 mph :Insane: it’ll still get hot. :idea:
 
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Maybe it's because I do a lot of towing in mountains, but my Allison only goes into 6th gear when I am going downhill, or if I switch it out of TH on the flats.

The duramax LBZ, LMM, and LML develop max torque at 1600 rpm, so even if you tried, you won't lug it at 1600. The Allison TCM will not allow you to "lug it" or over-rev it, even in manual mode, thanks to the TCM.

Manual mode only sets the highest gear the trans will shift into. If you are in a lower gear and manually "shift" to a higher gear, it will not go into that gear until the TCM is good and ready. Conversely, if you are in a higher gear, and shift to a lower gear, it will only shift to that gear if doing so won't put you over the redline.

But why over-think it; put it in TH, and let Allison do the thinking.
 

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What year are we working with? Some years there’s simple trans upgrades that could help.
Thanks for letting us know you have a 2003 & 8.1

“kendogg”
Hate to bump an old thread, but there's NOT a lot of first-hand cam info on these motors.

Is the OP still around? Did you end up swapping in the 270 cam?

Has anybody done first-hand A:B comparisons between the Comp cams and any of the Raylars? I just picked up an '03 with the Allison that needs a motor and figured while the motor is out I'll cam it. With my old '97 C2500 with the Vortec 350, I was rarely if ever above 3k rpm's towing unless I was in the mountains of TN. I consider that extreme circumstances, and this 8.1l should have all the power in the world to haul <10k lbs under 3k rpm on nearly any grade. I'm most likely going to re-gear my truck to 3.73's (4.10's currently). I'd rather have the fuel mileage, I'd rather make a little more low-end torque in the motor and gain the fuel mileage.
 
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