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Discussion Starter · #1 ·
New owner of a used 2007.5 3500 (10 days now) 6spd auto 2wd. Not like my old 95 but it will get the "Works" once I get the "Stock" issues sorted out.

So the truck has done this 3 times so far (what's really weird it has happened in the exact same spot about a mile from the house, weird...). No codes either.

So after pulling out on our road to the main hiway there's a little place to stop/accelerate into traffic. I come to a stop and when I'm clear I give a little pedal and nothing! I mean nothing. I get it to idle over to the shoulder and after a bit it now moves normally in gear. Pedal had no affect on rpm that I remember (kind of freaking out stalled in traffic).

The 2nd time (same exact spot) I manually switched the gear (+/- on the shifter) and it took off like normal.

The 3rd time (yes, exactly in the same spot) and did the manual down shift and away I go.

I figure the trans is hung in a high gear and the PCM (?) says no way you get any go pedal until I'm in the right gear.

Not sure what level the trans flash is at but will go to the dealer if I don't hear anything to the contrary here. I know my ole 95 wouldn't upshift when too cold but I don't think the temp is an issue in this case.

TIA:thumbsup:
 

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Wow! If opening the throttle gives you no increase in RPM, then I'd suspect an engine / electronic throttle control (ETC) issue. Even if the trans were in high gear, the engine RPM would still go up when you opened the throttle. Also, when you tap the (-) button on the shifter, it puts you into whatever gear you were in already. So if tapping the (-) button gives you "1", then the trans was already in 1st gear. I would concentrate on the ETC if I were you. Do you have a "lightning bolt" warning lamp on the dash? That's the ETC light.
 

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Discussion Starter · #3 ·
Wow! If opening the throttle gives you no increase in RPM, then I'd suspect an engine / electronic throttle control (ETC) issue. Even if the trans were in high gear, the engine RPM would still go up when you opened the throttle. Also, when you tap the (-) button on the shifter, it puts you into whatever gear you were in already. So if tapping the (-) button gives you "1", then the trans was already in 1st gear. I would concentrate on the ETC if I were you. Do you have a "lightning bolt" warning lamp on the dash? That's the ETC light.
Nothing on the dash lit up (I was looking for that symbol in particular). Did it again this morning (only 4 blks from the house and worse than before) but was a little different in that when I came to a stop the engine started to lug down and almost died. Gave it a little pedal while in gear and it came up on rpm's but wasn't happy. I popped into neutral and gave it a little pedal and saw the tach jump up. Put into gear and still lugging. I then hit the (-) button and it dropped into 1st and pulled away.

This morning was pretty cold (25deg) compared to the other times (maybe 35-40deg?). This has only happened when 1st starting out (cold) and so far not after driving it awhile or when air temp is up.


Thanks again
 

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Problems on cold startups only always make me suspect a bad filter, although your symptoms sound different than most. But the "lugged down" engine sounds like the Torque Converter Clutch (TCC) is dragging, which is possibly indicative of a bad spin-on (cooler return) filter. The 68RFE has two filters: flat main sump filter, and round spin-on filter. Both are inside the pan.

Try this next time: Start the truck and let it idle in Park (or Neutral) for ~30 seconds before you take off. See if you get the same issue. If not, then I would drop the pan, replace the cooler return filter (with a Mopar filter), and check the main sump filter and its seal (check for filter split open along side seam, or top cracked at the base of the snout, check that seal flange is pressed flush against the pump casting all the way around [not tilted], and that the filter snout is fully engaged into the seal).
 

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Discussion Starter · #5 ·
Try this next time: Start the truck and let it idle in Park (or Neutral) for ~30 seconds before you take off. See if you get the same issue.
Thanks for the quick reply!!! This morning I let it idle for about 5 minutes before moving (I didn't have an ice scraper). And this morning was different in that it seemed the torque convertor didn't release (only drove a few blocks and not over 20mph so not sure what gear or lockup condition the TC was in).

Just a side note on this. I've noticed that in forward gear (stopped so 1st I assume) the idle is at 700 rpm but when I put it in reverse (stopped) the idle is about 500 rpm and engine is almost dying.
 

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Thanks for the quick reply!!! This morning I let it idle for about 5 minutes before moving (I didn't have an ice scraper). And this morning was different in that it seemed the torque convertor didn't release (only drove a few blocks and not over 20mph so not sure what gear or lockup condition the TC was in).

Just a side note on this. I've noticed that in forward gear (stopped so 1st I assume) the idle is at 700 rpm but when I put it in reverse (stopped) the idle is about 500 rpm and engine is almost dying.
What do you mean by "torque converter didn't release"? If the TCC was applied, it would stall at a stop. The lower idle speed in reverse (I think the target is 550 RPM) is normal for 2007-2008 trucks.
 

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Discussion Starter · #7 ·
What do you mean by "torque converter didn't release"? If the TCC was applied, it would stall at a stop. The lower idle speed in reverse (I think the target is 550 RPM) is normal for 2007-2008 trucks.
TC lockup didn't fully release or was dragging.

If it was a manual trans I'd say it acted like the clutch disk was coming apart (clutch disks seperating) and dragging even with the clutch pedal pushed in (only way I can describe it).
 

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I wouldn't expect TCC drag (if filter is the problem) after a 5-minute idle. Problem with cooler return filter is a bad anti-drainback diaphragm, which allows oil in the converter to drain back into the trans sump while the truck sits overnight. Then when you start it cold, the slug of air from the converter gets pushed out through the cooler circuit, and eventually back to the pump. When this air reaches the pump inlet, you can get a momentary dip in line pressure (that allows the TCC to drag).

But after your 5-minute idle, that air should have been long gone. Also, the TCC drag is just momentary, not an extended event. So yours sounds more like maybe a bad TCC (bad converter).

Of course, you have to pull the trans to replace the converter, so I think I'd still start with checking the filters. If they are OK (or replacing the spin-on filter doesn't fix it), then it's time to pull the trans, then pull and inspect the pump. Failed converters usually leave telltale debris inside the pump. You'd also want to check the valves in the pump to make sure none are stuck or sticky. If you do this yourself, let me know since I need to give you some warnings about how to pull the pump without screwing up the thrust bearings in the input clutch assy (otherwise you will have a complete trans failure in 300-600 miles).
 
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