Whats the Deal with the Shift into Overdrive - 2005

[Giachino]

New to the forum... and diesels... . this is the big 3rd post...



Truck has 2200 miles on it... 05 4x4, Auto, 3. 73, Short Bed... .



Notice when I'm driving at a low to moderate pace (low to medium throttle)... . that the shift into 4th (Overdrive?)... . is different than the shifts between 1-2-3... . it's like it's short shifting (in dirtbike speak)... . and trying to lug..... rpm's drop to 1500... . not a very smooth process, seems kind of clunky or loose... . not sure what the hell a torque converter feels like so I'm not sure if it's locked or not at this point... . any thoughts?



Also at 2200 miles, I've been pretty kind to it, not flooring it or trying to haul ***... . real gentle on the warmup routine... . when is it safe to haul ***, I'm dying to floor it..... just to understand what she can do... .



Anyone from SoCal and into dirtbikes? I'm a fanatic, 9 bikes and counting... go to Cahuilla, Lake Elsinore, Soboba,... fat and out of shape, but I can twist a throttle with the best of em...



Love the truck... . 2nd dodge (previous 5. 9 gasser)... .

Great Forum, you guys seem pretty level headed, very few Haters!

 

[JTeague]

I think it is the converer locking that you are feeling. It usually locks around 45 MPH. It will make the the RPMs drop and you will feel the engine grunt so to speak. You can tell when the converter is locked by slowlyn easing into the throttle almost to the point of donshifting and the truck will accelerate as if it were a stick shift. the tach and the speedo will move in almost the same amounts. Hope this helps.



Jason

 

[juicedcummins]

Yes I would agree that is quite a shift but it is just the t/c locking up. I like seeing it trying trying to access some torque for a change. Mine seems to work and act better with the tow/haul on.

 

[macdaddy]

GIA chino

So Cal here. The O/D characteristics you are decribing are normal I had a 47RE in my 99 and I drove it that way for over five years before upgrading to a ATS w/ valve body,triplelock and Commander. The Commander allows you to have total control over the torque converter operation. As far as putting the 325/610 under load you should have at least 1K miles more so for the axels to losen up a little then go ahead and put her to work.

We also ride pretty much year round just about all off road Jawbone,Trona road,Cal city during the winter months, and then off to the pacific north west for some sick riding in Wa St and Canada we have a pretty big group pretty much evenly matched as far as truck loyalty goes Dodges. Fords and Chevey's but all diesels (makes for some good bench racing).

 

[Giachino]

"you should have at least 1K miles more so for the axels to losen up a little then go ahead and put her to work. "



Is that 1k more miles on top of the 2200 I already have for a total of 3 k, or did you mean have at least 1k miles total?



Thanks for the quick reply's guys.

 

[SSage]

You have enough break in miles. I waited 600 miles on mine, my truck was purchased for towing. So, even 600 miles empty was a hard task.



I recommend you change your diff lube after a few thousand miles. My axle oil was full of trash at something around 15K. Its a good idea to do an early axle oil change to get the metal out from break in.

 

[BHolm]

The convertor locking up at low speeds is actually my FAVORITE part of the way the trans works I let it lock up then give it some fuel, listen to the turbo spool, and off we go! This is how a TD truck should work IMO. In a Duramax Allison you get a bunch of rpms, a bunch of noise and never get to feel the grunt of the engine doing its work.



Using Tow/Haul will give you the same behavior but starting with third gear and often the shift to 4th is pretty harsh as the TC doesn't unlock, I love it. A little crude maybe but very effective, and you get to experience the power the way the six speed guys do :-laf if only for a couple of gears.