Houndog, towing about 4000 or so. Again the problem is, no matter what mode its in, it keeps shifting back and forth, back and forth, no matter how fast or slow, It shifts in and out, constantly. In 5th it turns 2000 at about 60-65, that would be fine if it would stay there. It CANNOT maintain 65 in 6th, period. Sent for build sheet, it PROBABLY has 3.56 gear. Thats hi, but that would be even better if I could lock it in 5th for towing, and let it go in 6th highway empty. 2000 RPMS are 2000 RPMS, thats fine, 1500 RPMS are 1500, and thats not enough towing 4000+ lbs. It will not lock in any gear no matter tow mode or not. Maybe its a computer glitch, hopefully they can re-program it. Thanks!

 

I have towed 7000lbs and ran in O/D no problem. ofcourse I have the Superchips with Advance trans tuning which isn't out yet for your 2012.
I can steadily maintain 11mpg on the highway @70mph towing that weight with last gear locked out running 2400rpms.

Stock trans tuning....You not suppose to be running O/D while towing. The gearing and programming is not meant for it. the reason it kicks in/out is because there is a specific pedal pressure that needs to be applied to kick it in/out and you must be right at that threshold where it lacks the power to maintain it's speed.
O/D while towing heats up the trans and is no good for it!

Tow/haul mode does extend shift point and locks out last gear
O/D off locks out last 2 gears. The 545rfe essentially has 2 overdrive gears if you look at the trans ratio's.

here's how the TCM works. You have partial upshifts and partial downshift schedules. these are dictated by throttle position(ultimately pedal position) The stock tuning could be that when going 65mph and with less than 7% TP the truck will stay in gear. If the truck falls below 65mph with <7% TP, the truck will downshift. ALSO, at the same time, if you are maintaining 65mph and increase the TP above 7%, the truck will also downshift. When the truck downshifts and you are at say 64mph and you keep the same Pedal pressure, the truck wants to upshift. it's a conflict of interest between the 2 up/down shift schedules and Factory tuning has them close like that for smooth shifting and so it's not over delayed like the older models. In my 2008, I'd have to mash the throttle about 1/2way before it would shift on the highway. about 3/4 in city before it would downshift. Now, it take 1/4" of pedal movement to do what I want!
This is far more advanced than other manufacturers that rely on inline pressure and rpms to shift the gears. Chrysler TCM is very involved and very awesome if you know how to manipulate it using a tuner. Hopefully Superchips can crack the newer codes and release the transmission control for the newer rams. i think they just did the 2011's so 2012 is next in line.

The Superchips link in my sig goes into further detail on how the shifting works. it's for the tuner, but still expalians further into detail on how it works. Stock tuning is the same except it's not able to be altered. just gives you an idea whats going on.

 

They have not cracked the 2011s yet, so 2012 is a little ways away yet im sure. Unless dodge used the same encryption on them HAHA. (Ya right!)

 

I have a 2012 2500 hemi for work and a 2011 2500 Cummins for my personal stuff and in both when I manually select 5th gear, it will not shift any higher than 5th (which seems to be where it needs to be, especially with the hemi)

Something is either wrong with the programming or its different in a half ton because it works in both of my 2500s

 

We-the-onforginin!! You said it buddy! I believed its not programed right. I dont care what you do, it will NOT lock in 5th, 6th. or whatever gear no matter how fast you're going or what mode you're in. Found out today from build sheet it has 3.56 gears. Maybe not the best for towing, but dealer should of known that. Regardless, it would be great if I could lock it in 5th. Will find ou thurs what the deal is. Thanks again everyone

 

Dirtydog, how do you suggest I not use O.D. (or 6th) towing if theres no way to lock it out? Thats exactly my problem!! Dodge engineering is going to look at it. They agree tranny is not right.

 

If my memory serves me right..... (so dont shoot me if i`m wrong)
5th or 6th, dosent matter, you`ll still have to overcome partial TC lock-up during towing.
Partial lock-up is usually there regardless, UNLESS, you reprogram it with a trans tuner.
In tow/haul mode, its not supposed to go into "full TC lock-up", just partial TC lock-up.
You might even have a bad torque convertor (no surprise, not uncommon for dodges)

 

Don't know if yours does but my OWNERS manual fully explains the features and operation of the automatic trans. Mine in tow/haul covert high gear 5th to a 1 to 1 ratio. Its not a OD anymore. It also does such using the select shift. In tow/haul it changes how the valving in the trans operates as well as the final gear being 1 to 1. In select shift the valving is not altered. There are other features of the transmission my owners manual addresses and explains.

 

Not right, here is the info from the manual. TOW/HAUL only locks out the second OD.

On vehicles equipped with 4.7L or 5.7L engines, use of
ERS (or TOW/HAUL mode) also enables an additional
underdrive gear which is not normally used during
through-gear accelerations. This additional gear improves
vehicle performance and cooling capability when
towing a trailer on certain grades. In ERS mode, first
through third gear are underdrive gears, and fourth gear
is direct drive. ERS fifth gear (Overdrive) is the same as
the normal fourth gear.

 

You are correct. I think I was trying to say the same thing sorta as 5th gear is now 4th gear. I just worded it wrong. High gear is no longer HIGH gear overdrive in tow/haul or ERS. Does not the 2012s operate in the same manor?