Is there ANY way to keep an '05 48RE out of Overdrive?

[Dixie Dawg]

I have a grand total of 430 miles on my truck, and the shifting into OD at 45 miles an hour is driving me crazy. I find myself wishing I was back in my '01. Anything I can do short of getting an aftermarket transmission to solve this problem?

 

[JFaughn]

I've got a 94 so its problly not the same , but I've got a factory button on the dash that is there to keep the T. Q. from looking up, but being that yours is newer my next guess would be like every other car & truck I've worked on , adjusting the throdle cable to trans. very little at a time to find a shift point you like, but first things first you've got a new truck go to the dealer and have them make you happy , thats why you pay the big bucks.

 

[tschwab]

I have a grand total of 430 miles on my truck, and the shifting into OD at 45 miles an hour is driving me crazy. I find myself wishing I was back in my '01. Anything I can do short of getting an aftermarket transmission to solve this problem?

In '05 DC changed the 48RE, there is NO OD lockout, you have tow/haul which actually works well when towing. I was used to the old way of locking out OD, now I just drop it in D and not worry about it. When I tow, I always drop it into T/H, seems to work very well. I have read several posts on this and I believe when in T/H the TC is locked in 3rd and stays locked? I'm sure someone will chime in on this.



I was concerned with this change at first, but after towing with my '05 and reading posts from others that have towed with an '05 48RE, I am convinced this is an improvement over previous 48RE's.

 

[TFucili]

I'm with you Dawg. I spend quite a bit of time on windy two lanes where you might see short stretches of 45-50 MPH and would prefer to keep it out of OD, as it lugs like mad when it upshifts that soon. I'm hoping that at some point there may be a reflash that lets the tow/haul button do double duty. It's not the end of the world, but it is annoying.

 

[MikeBeggy]

The trucks were changed in 04. 5 when the ECM was combined with the PCM. I installed a 1600 converter and the trans buddy kit from Dunrite. It changes the flow of oil and pressures. Also, upgrades seals and clutches for the increased pressures. At the same time. I bought a trans monitor from Bill Kederly which has indicator lights to let you know what gear your in and when the TC is locked. The T/H button will take the trans out of OD only when your foot is off the accel pedal... ie for engine braking down hills. As soon as you touch the accellerator, the trans shifts back into OD. Kind of a strange setup. BTW, with Bill's system, I have a button on the floor that will keep the TC locked until I touch the brake pedal. It changes the way you use auto for towing.

 

[MikeBeggy]

BTW Dixie, the shift that you are feeling at 45 to 50 is the TC locking. At light throttle, your OD shift occurs at 35 or so. If you want to disable the lockup, its controlled by a grounding circuit which you may be able to interrupt with a toggle switch. The computer shouldn't know but I couldn't say for sure.

 

[tschwab]

Mike - The '05's "IS" a different set-up from the 04. 5. You cannot lockout OD by pushing the T/H button.

 

[robertyoke]

The trucks were changed in 04. 5 when the ECM was combined with the PCM.





I started looking in to it and some trucks do not have the pcm as early as 09/03 prod. date ( 04 model year) they use the ecm to control the trans. and they had just O. D. lock out not the T. H. button.

so the diffrence is the program in the ecm but, I dont know if you could put the old program in the new truck. If you know a good DC mechanic I would ask him if it could be reprogramed.

-robert

 

[BHolm]

Your driving conditions must be different than mine. I love the fact that the trans upshifts and locks at such a low speed. The truck has plenty of power and I like how it pulls. The trans wont let you lug the engine. Lugging would be full throttle below the torque peak. If you get on it it will downshift. You might try running in T/H as it holds third locked longer than without it engaged.



If you want an auto that keeps the rpms up, try the Allison. That transmission hates to be in OD. It will gladly rev like crazy and burn fuel the same way. :-laf

 

[Tim]

I agree. I don't have an automatic but I'm usually in 6th gear at about 30 mph. There is no reason to rev your engine like a gasser, it has plenty of power at 1200 RPM to pull the truck.



Some of you guys have forgotten what it's like to drive a gasser. My truck has more power at 1200 RPM than my old gasser truck had at any RPM. Downshift and let the turbo spool and you've really got more... . but under 1,500 it still has more power than any gasser.

 

[MikeBeggy]

Hey Tschwab... . can you describe what your 05 does when you use the T/H button? I have only had one other TDR member to compare notes with. Since I installed my trans monitor, I can see which gear I'm in and it is very interesting to see how the ECM chooses what gear. The TC lockup comes in at very differnt driving conditions than I used to think by seat of the pants feel. My OD is locked out for engine braking i. e. down hills but only while my foot is not touching the accelerator. As soon as I touch the accel, it shifts back into OD and TC lockup. Also, I have to reset the T/H after each hill if I want the trans to hold the rig back in a braking mode. The feature of my trans control setup is that I can override the ECM and keep the trans locked until I want to "undo" the override. Real nice for long downhill grades.

 

[jcarey]

Mike Beggy, what trans monitor do you have?

 

[MikeBeggy]

Jcarey, my monitor came from a small place in Arkansas that was recommended by Dunrite Convertors. Bill Kederly builds the units to incorporate a trans temp guage, the lights to indicate what gear and TC lockup, and his main feature is a foot switch which allows you to lock the convertor at any time. It's an intersting feature that is very helpful when decending grades while towing. I'll have to check my desk to find Bill's number but Tony at Dunrite (a TDR advertiser) has the number.

 

[jcarey]

Thanks, Mike.

 

[pecandude1]

is there a fix for this yet?

 

[tschwab]

The '05 48RE does not have a problem, it works great! So to answer your question:No, there is no fix, because there is no problem.

 

[Lathe Guy]

tschwab, how can you say there is no problem. Everybodys towing situation is different. When I tow on certian grades the 48RE hunts all over the place. With or without cruise control. IT IS A PROBLEM for some of us.

 

[jwilliamson]

guess you shoulda gotta a six

 

[tschwab]

tschwab, how can you say there is no problem. Everybodys towing situation is different. When I tow on certian grades the 48RE hunts all over the place. With or without cruise control. IT IS A PROBLEM for some of us.

While I agree that everyones towing situations are different, I have to say, for me anyway, the new '05 48RE works flawlessly and shifts only when needed. I do not encounter any of the "hunting" you mention. I just returned yesterday from an RV vacation that included six mountain passes roundtrip, averaged 12. 2 mpg again (same trip as before) and the trucks performance was outstanding. Yes - I love the way the new '05 48RE works.

 

[jwduke]

Mine when towing (Between 60 & 70mph) sometimes downshifts, and takes forever to upshift. If I crack the throttle, it will upshift. Is this a problem? When it does this, I'm not using the tow/haul switch.