What is wrong with this trans? Auto is stalling engine!
 

Truck is a 98' Cummins with a 47RE. Every so often, only when it has been shifted from Park into Drive, or in Drive at a Stop, The Engine Stalls out. Everything seems fine, and my only guess can be the transmission since when it has been shifted into Drive (twice now) it stalls out instantly, and while at a stop in Drive, it has stalled (twice as well).

Does anyone know what could be causing this?

Also, many times when the truck has been at a stop in Drive, when I let go of the brakes and give it some fuel, the transmission seems as if it went into Neutral, then it finally his a gear and goes, but the grab of the gear is very noticeable.

I occasionally have the same issue from a stop, only when it's cold. Still looking into it, I'm going to try changing my trans fluid to a synthetic with a lower pour point. I have a feeling it might have something to do with the fluid thickening in the cold, but I could be wrong.

When all those times the engine stalled, things still were not warmed up yet. The times it stalled out from putting it from Park to Drive, when in the mornings it was about 30*, and the other two times it stalled from a stop, it was high 40*'s.. I don't think that would be cold enough for the liquid, but I don't know what the pour point is on the oil, but I recently changed it about 1k miles ago. But you could be onto something!

What is your idle set at? That could be part of the issue as far as stalling while shifting out of park.

My idle is right where Cummins suggests. It sits about 800 in Drive with the A/C on. So I do not think that is the problem, on a normal day, the engine doesn't even get close to stalling out.

what stall converter are you running? my 1750 rpm stall will kill the engine every time to about 40 degrees if it isnt warm.

It would seem like you may be experiencing what I had happen to me with a car...... the Torque converter would occasionally lock up and stall the engine ..... sometimes it would seem to own shift into like 2nd gear and when you would attempt to take off it would stall the torque converter and hence staling or lugging the engine .... might wanna check your filter and do a complete fluid FLUSH not just a filter change.....

Could also be stuck plunger in trans valve body ... try the filter and fluid flush ... keep us posted ... will dig deeper for ya :humm:

I am not sure what my stall is on my torque converter, I am thinking the trans is still factory, I bought the truck in October with 133k on it. I've only put about 2k on it since. I've kept my engine at factory output for this truck and don't plan on doing anything til I build a trans, either this auto, or swapping in a standard (Can't seem to make up my mind). So I don't think the trans has been overly abused, but with 135k on the factory stuff, I'm sure it's feeling week.

@4x4manonbroke would the car sometimes seem to shift itself into neutral at all at a stop? That's what mine seems to do a lot at an extended stop light. Then after a second, it would get into gear and go. When I got the truck, I changed all fluids, including the transmission fluid, it looked and smelled fresh, but I added new stuff and changed the filter. I would change it soon to test, but being that I'm usually at work when the sun is out, and at night it's dark and cold, I have a hard time doing that sometime soon lol .

[QUOTE=Sudia247;986469] would the car sometimes seem to shift itself into neutral at all at a stop?


that sounds like a fluid level issue? not a lock-up issue. no metal grimlens running around the trans pan?

[quote=turbo2332;986513]None, When I recently changed fluid, the fluid and pan were very clean. The Fluid level is also spot on..

i read your post and it reminded me of a ram i worked on a couple years ago
it was a 47 that the tcc lockup circuit was intermittantly grounding due to a flubbed up
wiring mod, it would shift through 3rd and then basically stall or lug
I talked to star today and my tech assistance advisor said that could possibility a
source of the problem either electrically or hyd circuit

although, i did have a 4L80 about two weeks ago that would rev then grab a gear hard due to the filter falling out of the pickup port, i dont think this is possible for your trans but worth checking out the pan just to see the state of things, fuzzy magnet is prob normal depending on milage but spikey is pretty much bad

this might actually be 2 different problems

good luck
scott:hellox:

yup sonds like electrical to me also .... check the valve body real close ... or have a trans tech look it over to see if there is any galling on any of the shift pictons or internal valve parts , betting u need valve body parts or electrical fix..... :tu:

It just might be electrical.. Today on my way to work I noticed while driving that the speedometer would turn up the gauge (ex: driving around 25 mpg and the gauge bumps up to 90 mpg then goes back down in about a second time frame). It did that twice in a 15 minutes time frame. and thinking back on it, I have seen it do that multiple times before, but didn't think anything of it..

speedo is controlled by VSS in tail end of transfer case. It is also a input for OD shift control solonoid wich might just be the source of your entire problem,

another thing that might be causing the delayed gear eng then slamming into gear would be the convertor drainback check valve but normally that only becaomes a issue after extended KO time

My speedo connection is in the housing of the rear axle, I'm guessing the first year of it like in the 24v. The T-case spot for it is blocked off where it would sit in the earlier years, I'm not sure if that would change anything about my problem..

The truck never has a problem shifting into OD.. and always does reliably..

I forgot to mention I do have a lock up switch wired through a relay, do you think maybe that the relay is giving out making the connection to ground the wire even though I am not flipping the switch? I'll have to keep it unplugged and see if it continues?