Running Rough
 

I have an 06 6.0 and when its the engine is cold the tranny runs like crap, or at least I think its the tranny. This started last summer and its gotten worse through the winter, but until the engine warms up, it doesn't like to shift. It'll hold the gear until 3000+ RPMs then it'll sit in the higher RPMs then when it finally does shift it slams real hard like the converter isn't engaging. But once the truck is warmed up, it shifts just fine. What could be my problem? Im not throwing any codes and the dealer has had it 3 times now and each time it comes back to me with the same shifting problem.

When was the last time the trans oil was changed. I just had this and it is supposedly that the oil is running to thick unil it gets flowing as stated by my mech. also need to change the filter under your front bumber for trans. mine is fixed now after doing that

Thanks! Ill have to give that a shot over the weekend and see if that fixes my problem

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its probably the tranns my buddys truck didi that and he got bigger gears and had it rebulit

Update: I changed the fluid and both filters on the tranny and it help a little, but last week when cold, it wouldn't shift out of 1st and when it finally did it started slamming through all of the gears until the tranny is warm, and after the fluid change, it feels like the top end is missing. When I get on the freeway it hits 65 then it takes its sweet time getting up to 80

Have you tried plugging in to the OBDII and checking if the TCM (Transmission Control Module) or TPS (throttle positioning sensor) are AFU? I fixed a Jeep once that had a malfunctioning TPS that was giving bad info to the TCM causing erratic shifting.

If these two are not the issue, your transmission may have deep rooted emotional issues. :td:

Mine's doing this as well, but I dont think as severe as you. Mine will only do this if its colder than 20 degrees F out. I usually let it warm up a little before driving in that cold anyways. I have a reman tranny with less than 10k miles on it too.

I haven't checked any of that or so I don't think... I have the Edge Juice Platinum and it isn't pulling any codes, but I should probably take it to Auto Zone and have them check...

I don't know if a diesel even has a TPS, but if it does, an Ohms meter will tell if it is working properly. If you hook up and simulate useage there should be an even/linear increase in Ohms, not a jerky/spiking read out.

However, with all of the electronic, there has to be a TCM and it has to get its input from somewhere.:humm:

There are TCM's on these, but the Edge can't do anything for programming it, so I don't think it's going to do anything for reading it. An SCT would let you data log what is going on since it can actually access the TCM.

Are you positive it's actually the transmission. It could also be injector related as well, which is far more common.

the hard shifting and holding out on gears sounds like solenoid packs.... but still that sounds very wierd. did you have the tranny flushed or just changed the filter with new fluid?

Well, I figured I'd update this in case some one else is having this problem... I don't understand it all just yet, but I had 5 injectors go out and somehow it effected the transmission... I don't know how or why but I got it back this afternoon from the dealer and it feels like it did when it was brand new

im having the same problem but i think its a diffrent issue cause when i was at the dealership last (2 months ago) they replaced 6 injectors. and for me this happens when its 70 outside and the trucks set for more that 4 hrs or so.

as a side note to everyone that has this problem if you go easy into the throttle and when it hits 2500 rpm come off the gas a little the truck will down shift

Mine had all of those symptoms last fall when it was still mid 70s. Thats when it really got bad and we had a fairly cool winter here and the truck hated it. I drove it all last night and its so nice, but I think I'm goig to start looking into taking care some of the weak areas before I go out of warranty next spring and hopefully it'll save me some heartbreak

ok i think i know what the deal is.

you have a number of injectors that are going sour, so the ecm isnt getting a correct reading that the injectors are doing their job correctly, so the ecm is telling the tcm (trans control module) to hold out until the proper engine speed/torque requirments are reached. :jump:

Thats sounds about right.... After thinking bout it, not having all the injectors working properly until it warmed up, would cause the tranny to act that way... I'm glad I bit the bullet and took it to the dealer, I was ready to replace the tranny with a built one. That would have sucked to have dropped that cash and not have fixed my problem...

yea but a built tranny would be nice..... :c: hahaha