OBDII code - P0894.....

Zoediak · Mar 5, 2012

Ok.. so, my CEL came on for the first time in my Chev Truck...

Put on the scan tool and get the code and i get the following code:

P0894 - Generic - Transmission Component Slipping
pic:

so.. I have done a bunch of internet searching, to find out that no one really knows what it is that is 'slipping'...

so, when this happens, it shifts really hard, actually reminds me of my chevelle shifting with my stage2 shift kit...
it also raises my tranny temp about 40 or so degrees...

when this happens i am not hauling or towing anything, just normal driving.

after I park the truck for a while, it seems to work normally for a while, then all of a sudden it starts to freak out again.

and this freakout does not happen all the time, it has happened like 3 seperate times in the last 2 weeks, this weekend was the first time it threw a code...

my probalem is, I don't want to be throwing a bunch of parts at it to find out that it didn't solve the problem (like i have read so many others have done).

so, is this the torque converter failing or what??

the fluid is in good condition and not burnt or anything...

any advice or direction forward would be great...

edit for truck info...

2007 Chevy 2500HD 4x4 Crew Cab Standard Box
6.0L engine
126k miles

regular oil and fluid changes...

ChopTop84 · Mar 5, 2012

Are you able to monitor things like input shaft speed, or line pressure with your scanner?

Elevated temps usually means something is slipping, and the one thing that slips the most is the torque converter.

If you could monitor your input shaft speed, and compare it to your engine RPMs and if your TC has locked up or not, you might be able to tell if your just burning right thru the TC or your lockup clutches, or maybe the line pressure to hold the clutches is down.

It could be something as simple as some little electric solenoid not working right (would fit the intermittant occurance better), or as bad as your TC starting to fail.

Have you actually towed lately to see if it will fail while towing, or fail WORSE while towing? Might want to keep it close to home on that test.

Zoediak · Mar 5, 2012

I have not tried towing anything with it since any of this has happened.

My scanner has the ability to show a bunch of live data, but just not sure if it will show all that..

(it is new to me)

I will plug it in before I leave work this afternoon and browse through the advanced menu and see if it will show any of that data...

thanks for the advice..

ChopTop84 · Mar 5, 2012

Depending on the scanner, they may call it "turbine speed" for the torque converter, but once the TC locks, your engine RPM and input shaft RPM should be the same. Output shaft speed obviously will depend on the gear you are in.

On the ford 4r100s, the computer watches the input and output shaft speeds, calculates what gear your in, and if the two speeds dont match a fixed set of numbers, it throws a slippage code and usually means the internal clutch plates arent holding (possibly due to the wrong fluid, too much power, or not enough line pressure).

Im just guessing your tranny has a similar form of reporting. But since its not pinpointing the location, that leads me towards either the TC or line pressure, but to be honest, Im not really familiar with your model trans other than I know they have a LOT of electronics in them.

crash2 · Mar 5, 2012

The ECM/PCM/TCM monitors input/output speeds within the trans and that code is a reflection of a clutch pack either slipping or slow engagement.

Drop the pan and inspect whats sitting in the bottom of it and go from there.

But that code is usually an indicator of something internal.

Zoediak · Mar 5, 2012

crash said:
The ECM/PCM/TCM monitors input/output speeds within the trans and that code is a reflection of a clutch pack either slipping or slow engagement.

Drop the pan and inspect whats sitting in the bottom of it and go from there.

But that code is usually an indicator of something internal.

ok... looks like i will aquire a new pan gasket and fluid and check it out as well...

lets hope it is all nice and neat inside that pan.. :redneck:

JOOP · Mar 5, 2012

Time to trade it in, is what it means.

zukkev · Mar 5, 2012

Should have a reuseable gasket Dusty :awesomework:...just drop that bitch!!!:haha:

Zoediak · Mar 5, 2012

zukkev said:
Should have a reuseable gasket Dusty :awesomework:...just drop that bitch!!!:haha:

Will do when i get home this afternoon (after I go buy some fluid)

and as long as it isn't pouring rain!!!

Hip · Mar 5, 2012

my suburban has had that code for over ten years now and i cant make it go away. my tranny does not slip.

i have towed a LOT and my trans does not slip.

i can clear it long enough to pass smog each two years then after about two weeks it comes back.

i think in my case it just shifts slow maybe but it shifts nice and smooth and dont slip so i have left it be.....:redneck:

Byke · Mar 5, 2012

Assuming you have the 4L80E.....the most likely cause is the torque converter. If your scanner will data stream then you should be able to check T.C slip by driving it with scanner hooked up. You want to check % or rpm T.C. data when the T.C. is engaged (freeway is the best place). You need to drive at a steady speed and move the throttle a little up and down. If you let all the way off or feed it too much throttle too fast the T.C. is commanded to turn off. The RPM should stay AROUND 0 and change a little to the plus and minus side. If the RPM difference is too great (don't remember the exact # that is "safe" off the top of my head) then the computer puts the trans into failsafe and that is why the shifts get hard. And yes, it has a reusable gasket, I would suggest you reuse it and NOT replace it with an aftermarket cork or paper gasket.

Hope this helps

zukkev · Mar 6, 2012

With yours happening suddenly like this Dusty...check to see whether there's any Bulletins regarding this code (seems to me there is regarding a cracked solenoid body for the TCC...)...Just did a quick search, and there does seem to be some reference to a Bulletin out there.
Now finish yer Jeep!!! :fawkdancesmiley:

Zoediak · Mar 6, 2012

Byke said:
Assuming you have the 4L80E.....the most likely cause is the torque converter. If your scanner will data stream then you should be able to check T.C slip by driving it with scanner hooked up. You want to check % or rpm T.C. data when the T.C. is engaged (freeway is the best place). You need to drive at a steady speed and move the throttle a little up and down. If you let all the way off or feed it too much throttle too fast the T.C. is commanded to turn off. The RPM should stay AROUND 0 and change a little to the plus and minus side. If the RPM difference is too great (don't remember the exact # that is "safe" off the top of my head) then the computer puts the trans into failsafe and that is why the shifts get hard. And yes, it has a reusable gasket, I would suggest you reuse it and NOT replace it with an aftermarket cork or paper gasket.

Hope this helps

thank you for the advice.. I will check this out on my next run down the highway...

:awesomework:

Zoediak · Mar 6, 2012

zukkev said:
With yours happening suddenly like this Dusty...check to see whether there's any Bulletins regarding this code (seems to me there is regarding a cracked solenoid body for the TCC...)...Just did a quick search, and there does seem to be some reference to a Bulletin out there.
Now finish yer Jeep!!! :fawkdancesmiley:

Thx Kev... I also read about a few instances with a cracked solenoid. Then i also read that a lot had replaced and the problem was still there.

I didn't get a chance to drop the pan last night as I had to run to the dealership to get the 'special fluid' for the transfercase. Figured while I am under there, I may as well change that fluid as well...

haha

and yes.... i need to get my jeep done!!! :fawkdancesmiley:

:redneck: