Ramcam

I had my truck in for a a droneing problem and while there they did an update on my towhaul mode.This update now lets me hold 3rd gear without going into od they said i would get more use of the tork of the motor and a 1 mile per gal increase it is supposed to be similar to the way tow haul worked on the older trucks not sure what that means.I'm going to drive it this way for awhile see what happens ,if i dont like it they will switch it back.To get overdrive i think you have to turn towhaul off when you want to cruise at high speeds.I could'nt really test it in rush hour today i'll post my experience.Anybody else have this done yet?

bob4x4

I prefer having the tow haul mode,I don't need to lock out my OD.

Bob

GSW

Sounds interesting. Keep us updated on your results.

anni2VADER

theres a thread over on TDR i think about this and the guys are concerned that the tranny wont lockup as agressively as it does in tow/haul mode. yes please keep us posted about your results. thx

grantx5

What is the TSB #?

Ramcam

i don't have the tsb number the service manager was not in when i picked up my truck.Well i got it out on the highway today and overdrive does not kick in at 50 miles per hour anymore.Travelling at 60 miles per hour i'm running at 2500 rpm which is a bit noisy but i can see if you were towing a heavy load it would really put you in the torgue curve when pulling long hills.If you can find the tsb on it it would provide alot more info.They also said the overhead consloe readings would be alot more accurate.An increase in fuel mileage aprox 1 mile per gal.

HorseHauler

SWEEEEEET!! I have been wanting this ever since I traded my 03 for this 05. Please let us know the TSB # if you can, or does anyone have a link to the thread over at TDR? I hate tow/haul mode when hauling... i miss the O/D lockout

Deaver

Here ya go

NUMBER: 21-006-07
GROUP: Transmission
DATE: March 20, 2007

SUBJECT:
Flash: New 48RE Feature That Allows Normal Shift Schedule With Full Disable Of 4th Gear Overdrive

OVERVIEW:
This bulletin involves selectively erasing and reprogramming the Cummins Engine Control Module (ECM) with new software.

MODELS:
2005 (DH) Ram Truck (2500/3500)

NOTE: This bulletin applies to vehicles equipped with a 5.9L Cummins turbo-diesel engine and a 48RE automatic transmission (sales codes ETH and DG8
respectively).

SYMPTOM/CONDITION:
1. The following enhancement is included with this software:
a. A new 48RE transmission feature that will allow normal shift schedule with full disable of 4th gear (overdrive gear), when the customer selects the Over-Drive (O/D) switch.
Prior to the implementation of this new transmission feature, the use of the O/D switch changed the automatic transmission shift schedule from a “normal” shift schedule to a tow/haul mode shift schedule, and allowed 4th gear (overdrive gear) engagement.
This new transmission feature will not change the transmission shift schedule, but will allow full 4th gear overdrive disable (lock out). With this new feature the customer will have the “normal” shift schedule with NO overdrive (4th gear).

NOTE: To enable the new 4th gear disable feature, the ECM must first be
reprogrammed (flashed) with the latest software level, and then the 4th gear
disable feature “O/D OFF ENABLE” must be selected (turned on) using the
DRBIII®. Tow/haul mode is not an available feature whenever the DRBIII® has enabled the “O/D OFF ENABLE” selection.

HorseHauler

Awesome, Thanks a lot. So im confused like normal, is it going to be a double hit on the button like the new trucks or what to get the O/D off feature?

also maybe I am hearing bells in the background for available exhaust brake with this mod...????

gerry

to bad they couldn't have made it like the 06.. push once for tow haul and a second time for od lock out...

Also It looks like if you want this you have to upgrade to the reverse honk software ... arrrrggggg.. is it worth a honking horn to get the od lockout???

Gerry

Ramcam

No it is not a double click on the tow button when i got to 60 i just hit the button once and od kicked in.Hit it again and your back into towhaul without od.The guy said it is setup like the older towhaul modes early 2000 years not sure of any pros or cons with this.He asked me to try it see if i like it if not he will set it back.

grantx5

Not sure I understand how it works. Does the reflash switch T/H to OD ONLY or can you still access T/H after the reflash is done????

My understanding is T/H will go away, replaced by the ability to lockout OD when the button is pushed.

To ever have T/H available again requires a reflash that does away with the OD LO and replaces it with T/H just like it came from the factory.

Correct? Incorrect?

GSW

My understanding is the same as yours. Either you get normal tranny + tow/haul or normal tranny + OD lockout.

They get soooo close to doing something right and then fall just short. I guess I'll chalk this one up as ExhaustBrake the Sequel.

grantx5

Well said...

HorseHauler

interesting. Sweet I am now confused a bit more