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Yesterday I was towing my 24' livestock trailer with 8 horses, and my truck was wanting to stay around 1,750-1,800 RPMs even while ascending a fairly steep grade. It felt to me like the truck should downshift to 5th or 4th gear. The truck sort of sounded like it was bogging down, and I ended up downshifting manually so I had more power on hand.

Am I overthinking it and should just let the tranny do it's thing?

I have a 2018 dually with the Aisin, 4.10 gears and 12k miles.

Thanks
 

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I routinely downshift manually. I pull a 14K lb 5er with the 68rfe and 3.73 gears. 6th gear is always locked out when towing heavy and I will shift down to 4th before starting up a long grade.


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I usually tow( 18,000 lbs) on secondary roads and often manually shift to keep my engine in it’s sweet spot. My Aisin’s programming also leaves a little to be desired.
 

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Nope. Just put it in tow mode and set the cruise control. Grossing 18k no issues on some of the worst grades in the us. I40 over the nc and tn border is ranked in the top ten grades in the us.
 

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Yes! I downshift manually with my 2016 3500 drw aisin and 4.10 gears. Anything over 20k trailer weight I feel the transmission doesn’t downshift fast enough. If I don’t downshift it kills my speed at the beginning and I never can get it back. Plus it runs cooler.
 

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For the most part, I let my Aisin do its thing, but...

If the sound tells me that the engine would like to rev a bit more, or it feels like it, or the temps suggest that I should, I downshift manually.

I've actually wondered why more people don't drive an automatic more like a stick. Just because there's no clutch pedal it doesn't mean that we can't shift them as we please. Or shouldn't we?
 

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I drive my 68 like it's a manual!! Loaded or not I down shift coming down grades or coming to a stoplight. I have installed the Center Console shifter in my last 3 trucks for manually shifting easier!!
 

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Yes! I downshift manually with my 2016 3500 drw aisin and 4.10 gears. Anything over 20k trailer weight I feel the transmission doesn’t downshift fast enough. If I don’t downshift it kills my speed at the beginning and I never can get it back. Plus it runs cooler.
What he said
 

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Run it in tow mode, down shifts when it needs to on most of the calif, nev, & az desert grades. On an extremely twisty, steep, 2 laner in the eastern sierras I manually shift it to use the exhaust brake downhill to keep all the brakes cool. It’s a 2nd & 3rd gear climb and no need to push it. It works best @ 1800 rpm range with what we tow.
 

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I routinely downshift manually. 6th gear is always locked out when towing heavy and I will shift down to 4th before starting up a long grade.


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Same
 

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The programming in the Aisin is good, but similar to the GPS, it will get you there but not always the best way. You can feel when the Cummins is in the sweet spot and the transmission programming isn’t set to keep it there. When coming to a grade (of any magnitude) I will manually downshift to keep the RPMs in the 1900 - 2200 range. The truck runs smoother and cooler. When towing I only use cruise control when traffic is light and on long fairly level stretches of road, like portions of the 80 East of Reno, but never if there are grades.
 

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You can feel when the Cummins is in the sweet spot... I will manually downshift to keep the RPMs in the 1900 - 2200 range. The truck runs smoother and cooler.
I suspect that many Ram owners are so used to having the engine chugging and vibrating along at 1,200 rpm, due to 3.42 gears and tall tires, that they see that nice 1,900 to 2,200 rpm range as excessive.

Unfortunately, they don't know what they're missing. I do; they're missing a downshift or two.
Okay, it's hard to miss a shift with an automatic, but you know what I mean.
 

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^^Thanks Jimmy its the only thing that annoys me with the truck is the transmission programming - I honestly would rather just leave the emissions intact and get the transmission behavior programmed better, yes I know I can leave tow/haul on but it would be nice to not have to manually downshift it, or run tow/haul when tooling around in the 50-60mph range on suburban roads as I can definitely feel it lugging when its in 6th at 50mph

Alternatively I have been thinking of investing in regearing pre-emptively for 35's, that would take care of it without reprogramming the transmission -

I know a bunch of guys are gonna say *oMg YoU aRe OvRkiLL yU DuN NeD tA rEgEaR fUr 35'zz* but I cant imagine going up in tire size for this truck without changing the gear ratios because it lugs a ton for me on the stock 33.5" tires and transmission programming-
 

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I happen to think that you should re gear for stock tires, having driven a '17 2500 a couple of times, once with about an 8,000-lb. tow. It felt like I should be doing at least 90 mph for the engine to begin to be happy.

As it is, I'm usually doing about 80 with my 3.73 geared DRW and its smaller tires. That puts it at about 2,000 rpm, which the engine really seems to like.

Oh, and I use tow/haul at least 95% of the time.
 

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I came from a 2500 with 3.42's and had a true 35" tire on it. It has taken a bit to get used to turning 2k rpm at 70 with my Aisin and 4.10's. But the truck seems happy doing it.

I suspect that many Ram owners are so used to having the engine chugging and vibrating along at 1,200 rpm, due to 3.42 gears and tall tires, that they see that nice 1,900 to 2,200 rpm range as excessive.

Unfortunately, they don't know what they're missing. I do; they're missing a downshift or two.
Okay, it's hard to miss a shift with an automatic, but you know what I mean.
 

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I happen to think that you should re gear for stock tires, having driven a '17 2500 a couple of times, once with about an 8,000-lb. tow. It felt like I should be doing at least 90 mph for the engine to begin to be happy.
I agree completely - even stock tires should get a regear, but if I ever go up in size I absolutely will do so - I'll make it a point to turn on Tow/Haul with the EB everytime I start the truck -
 

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I agree completely - even stock tires should get a regear
I hear ya. My parents (now retired and full time RV’ers) just picked up a 2019 3500. It’s setup exactly like my 2015 3500 (Aisin, air bags, etc.) EXCEPT for the fact the 2019’s come with 3.73 gears (well, it does have 1000lb/ft of torque now). It drives and tows so much nicer than mine. Still can’t believe Ram didn’t allow us to order 3.73 gears for the 4th gen trucks. :spank:
 
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