Main IndexAuto Repair Home Search Posts SEARCH
POSTS
Who's Online WHO'S
ONLINE
Log in LOG
IN









Trans shuttering (slipping in & out of gear) when coming to a Stop


Search for (search options)
 



Sparkles
Novice

Oct 9, 2015, 6:48 PM

Post #1 of 19 (1987 views)
Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

I have a 2003 Jeep Liberty a when I applying the brakes with a the engine revving at 1000 rpm or a little lower (a slight torque stall). Can feel the clutches disengaging & re-engaging very rapidly until the vehicle comes to a complete stop; should say the disengaging & re-engaging slows down with the vehicle when it slows down. Any ideas??
And it's not the brakes doing it either!!!


(This post was edited by Sparkles on Oct 9, 2015, 7:22 PM)


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Oct 10, 2015, 1:41 AM

Post #2 of 19 (1947 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

Not sure what you mean by clutches engaging and re-engaging? Seems more like a torque converter lock up issue.


I'll just suggest a couple things and leave this to this sites transmission specialist. Check for vacuum leaks especially to brake booster in this case as low vacuum will signal higher load on engine confusing signals to the operation of engine and trans.


You could get codes read in full and post the #s to speed up suggestions,


T



Sparkles
Novice

Oct 10, 2015, 4:02 AM

Post #3 of 19 (1939 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

I didn't mention this in scenario my earlier post; when your backing up on a slight incline, like a driveway. For example: I was turning around on a field approach (driveway to a field) and there was a slight decline to it from off the highway; so, I was backing up very slowing, and it does then too. It's like the going in & out of Reverse (clutches disengaging & re-engaging). It's like it felt like one of the tires were spinning in a very small puddle of mud, but they weren't.
Doesn't the Trans Fault Codes not turn on the Check Engine light? As far as Codes; the only one there when I read it was a EVAP code.


(This post was edited by Sparkles on Oct 10, 2015, 4:07 AM)


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Oct 10, 2015, 4:34 AM

Post #4 of 19 (1932 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

OK, Quote your whole first post again ">>I have a 2003 Jeep Liberty a when I applying the brakes with a the engine revving at 1000 rpm or a little lower (a slight torque stall). Can feel the clutches disengaging & re-engaging very rapidly until the vehicle comes to a complete stop; should say the disengaging & re-engaging slows down with the vehicle when it slows down. Any ideas??
And it's not the brakes doing it either!!!<<"
This begs questions and descriptions do.
Back up here some: Is trans fluid filled to proper level? I ask that now but should be first thing checked. On a slope now you said it can act up. I don't care too much what surface unless you are slipping just that it's a slope. Any vehicle if driven thru high water or muck factor that.


* Trans codes and other codes don't always show up with the CEL light staying lit until it's been there long enough. Better code readings will expose codes pending. Try again with a better machine or any to begin with free at some parts outlets and other places but get #s as said not an interpretation or what to buy!


* Why is idle @ 1,000 RPM? Did you mean you are holding throttle there? If not a vacuum leak could do that or unmetered air entering intake that is interpreted by engine and transmission controls to adjust fuel delivery, spark timing, what gear to be in, when to up and down shift, when to engage torque converter lock or unlock up, and tons more also calculating in your requests driving it with a gas and brake pedal, which gear chosen and also how fast you are going. Whew - that and more in a nano second.
So, I thought of vacuum leak because of what looked like a high idle not said if you did that or that was just the speed of engine messing up all those other things. Low vacuum by leak or load on an engine can and will dictate what it should do like idle and when to lock up a converter. Low vacuum in manifold will be seen as a load as if you are requesting more power whether you are or not with a leak.


Other still real important is the trans guy isn't here yet. So far trans may not be the issue at all to me. Some will shudder if slipping for real like a rapid fire feel like brakes on and off but at trans for traction. Some GMs used a button to shut that off I think marked T/C for "traction control" as it was annoying to many folks especially in certain slippery situation they otherwise understood like snow and ice common to many area in that time of year.


Other again: Off dry common paved level roads you can slip and not realize it. I drive vehicles too. Plain wet grassy anything it's easy without wild slopes or force. Certain vehicles especially with applying brakes will take ONE spinning or locked wheel as a problem and activate ABS or traction controls to help or so it thinks and could be normal.


Still question why the RPMs so high - it matters,


T



gsferraro
Veteran

Oct 10, 2015, 6:41 AM

Post #5 of 19 (1924 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

Hello,
First thing is check fluid level, engine running in neutral. It almost sounds like the converter is not releasing but im not sure thats what it is. How does this car drive foward? Does this problem only happen when hot? Trans codes will turn on the check engine light. Was anything done to this jeep before this problem started


kev2
Veteran
kev2 profile image

Oct 10, 2015, 9:04 AM

Post #6 of 19 (1919 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

always scan....do not rely on bulb.
recent work- anything could be a clue.


Sparkles
Novice

Oct 10, 2015, 5:45 PM

Post #7 of 19 (1905 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

Don't want sound like an #$%^&%$; I am a JM/RS HD Mechanic; oil level was First thing I checked; secondly in previous post it shuttered "like it was in a small mud puddle", and the approach was gravelled.

This vehicle doesn't have TRC, just ABS and it's not that.

Heavy gear do have automatic transmissions too, but they're engineered a little different then the Automotive industry.

My first thought was the Torque Lock Up; but it has lots power torque off the start, so it kind of ruled that thought out of mind; second was a Speed Sensor, but I'm a I little unfimilair with Automotive engineering of transmission.

And asking why the engine revving at a 1000rpm; and why am I resting my foot on the accelerator pedal. The first it did it I didn't realize that I had my foot resting on the pedal, and when it shuttered I noticed it right way and said to my wife something very wrong with this vehicle, I tryed to duplicate the seneraio, and I couldn't till one day we were liking at somebody's RV that they were selling on the side of their driveway (these people lived off a major highway and turning around on their yard the thought was just to back up onto the shoulder instead and this is when I noticed it again for the second time. But now I've been able to figure out to make it act up by holding accelerator pedal just below or at a 1000rpm. And what I also found is when the vehicle is at Operating Temperature is when I make it happen, when every thing is Cold, it don't do it.
I did have it read for codes at local garage and nothing showed up. I also have a Scanner as well and it don't show anything relating to Transmission codes; just the EVAP code, which I think it's my fuel cap (oh by the way if this makes a difference to you guys, this vehicle is a gas job). In my 25+ years of wrenching, there are times where Sensors and other fault don't register in the ECM as a fault.
K, I realize I may have forgotten to mention more stuff, but the mind is a little tapped out at the moment. But any other questions, keeping on asking them and try my best to answer them.

Oh forgot answer buddy question; this vehicle is stock. And we bought it a little over a year ago, and we bought with a Lubrico Warranty program and had it in the shop several times (about 5 times) relating to this issue and nobody seems to know why it does this. So I'm taking it on myself to figure it out (with your guys help too).


(This post was edited by Sparkles on Oct 10, 2015, 5:58 PM)


gsferraro
Veteran

Oct 10, 2015, 6:54 PM

Post #8 of 19 (1898 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

Hello,
Ok, so since it happens hot and not cold, you may have a pressure loss when the trans heats up, or maybe an issue with the valvebody. This unit is called 42RLE, You mentioned that you had this at a shop a few times, do you know if they happen to look at C.V.I (clutch volume index) values, these numbers show internal wear.


Discretesignals
Ultimate Carjunky / Moderator
Discretesignals profile image

Oct 10, 2015, 7:08 PM

Post #9 of 19 (1898 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In


Quote
My first thought was the Torque Lock Up; but it has lots power torque off the start, so it kind of ruled that thought out of mind


Just to add: The torque converter on modern vehicles have a clutch that mechanically engages the engine to the transmission. They engineered it that way to reduce transmission fluid temperature and to increase fuel mileage. A converter without a clutch is going to have slippage between the impeller and the turbine that creates heat. By locking the turbine to the impeller mechanically you eliminate that.

The torque converter clutch should only be applied at steady cruising speed, usually in 3rd or OD gears. If the torque converter clutch stays engaged, for some reason, while your coming to a stop, it can cause shuddering or even stall the engine out. A torque converter clutch that doesn't disengage when coming to a stop would act the same as a manual transmission coming to a stop without disengaging the clutch disc.





Since we volunteer our time and knowledge, we ask for you to please follow up when a problem is resolved.

(This post was edited by Discretesignals on Oct 10, 2015, 7:14 PM)


Sparkles
Novice

Oct 10, 2015, 7:58 PM

Post #10 of 19 (1888 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In


Quote
: The torque converter on modern vehicles have a clutch that mechanically engages the engine to the transmission. They engineered it that way to reduce transmission fluid temperature and to increase fuel mileage. A converter without a clutch is going to have slippage between the impeller and the turbine that creates heat. By locking the turbine to the impeller mechanically you eliminate that.


K, in the Heavy world they called it a "Torque Lock Up" they use it for the same reasons, it's like a calling it an Overdrive.
So if the clutch doesn't disengage properly, you lose all your Torque (push power from a dead stop). And also if stays engaged (locked up) the transmission & torque temperature increases very quickly from it trying to push itself ahead. In the Automotive world you'd smell hot oil, and possibly pushing oil out the transmission vent, correct; in the Heavy world you got gauges in the cab and sensors throwing High Temp codes.
K, back to your post I understand what you mean by the shuddering from the torque; but would this do it even if your on even ground start driving forward or reverse very slowly then?


(This post was edited by Sparkles on Oct 10, 2015, 8:00 PM)


Sparkles
Novice

Oct 10, 2015, 8:02 PM

Post #11 of 19 (1884 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In


Quote
Ok, so since it happens hot and not cold, you may have a pressure loss when the trans heats up, or maybe an issue with the valvebody. This unit is called 42RLE, You mentioned that you had this at a shop a few times, do you know if they happen to look at C.V.I (clutch volume index) values, these numbers show internal wear.


42RLE is the model of the transmission I have in this Jeep?
No I never saw the C.V.I. values, they did give me a print out of what was there for codes though.


Sparkles
Novice

Oct 10, 2015, 8:05 PM

Post #12 of 19 (1882 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

Oh ya, did forget to mention that the local garage mechanic did change out the TPS; when I went to pick the Jeep and they told me what they had done, I thought, Ok, I could see this might have been the issue. But, NOPE it still continues to do the samething, problem still exists.

Does anyone know where I could get my hands on a Parts Break Down (or a Parts Manual) on this transmission/torque, free one I prefer?


(This post was edited by Sparkles on Oct 10, 2015, 8:10 PM)


Discretesignals
Ultimate Carjunky / Moderator
Discretesignals profile image

Oct 10, 2015, 8:15 PM

Post #13 of 19 (1877 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

Not sure if a torque converter clutch is used the same way in the heavy equipment industry, but the torque converter clutch in automobile doesn't multiply torque or cause the transmission fluid temperature to increase if it stays engaged. By mechanically coupling the turbine to the engine, with a clutch device, you eliminate that loss of energy(heat).

All the clutch does is lock the engine to the transmission just like when you lock the engine to the transmission on a manual transmission equipped vehicle when you release the clutch pedal. The turbine in the torque converter doesn't spin at the same speed as the impeller and because of this the energy that is lost comes in the form of heat.

The clutch can't be engaged when you come to a stop because the turbine slows down and stops and the clutch is mechanically connected to the turbine. If the clutch is engaged to the housing which is driven by the engine, the engine will stall out when the turbine speed gets too low.

Here is an illustrated parts break down of the 42rle, but it really won't help you much because you need to have it diagnosed to figure out if you have some sort of electrical or mechanical issue. Gary is the guru on that.Cool

http://worldwidepartsoutlet.com/.../42RLE%20Diagram.jpg

Eric does a great job of explaining the operation of a torque converter and it components...check it out:
https://www.youtube.com/watch?v=pTfipsejqS0





Since we volunteer our time and knowledge, we ask for you to please follow up when a problem is resolved.

(This post was edited by Discretesignals on Oct 10, 2015, 8:39 PM)


kev2
Veteran
kev2 profile image

Oct 11, 2015, 7:25 AM

Post #14 of 19 (1850 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

Sparkles let us know if you are still following this thread-
I am seeing different descriptions - terms and verbs I guess


Sparkles
Novice

Oct 11, 2015, 5:27 PM

Post #15 of 19 (1833 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In


In Reply To
Sparkles let us know if you are still following this thread-
I am seeing different descriptions - terms and verbs I guess

Yep still following this thread


kev2
Veteran
kev2 profile image

Oct 12, 2015, 7:07 AM

Post #16 of 19 (1810 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

I can not describe the issue SO when I see9ng things close to your description...


always talking about speed 30-40 mph....not rpm- yes no?
a feeling like driving over 'rumble strips'....
described as the TCC on off a surging as vehicle slows...


hoping it is simple I would ask - have you serviced trans ? only ATF4 I think?
tried lube guard for this TCC issue?


GTG LATER


gsferraro
Veteran

Oct 12, 2015, 3:02 PM

Post #17 of 19 (1808 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

I would like to know what the cvi value is for the low/reverse clutch, to eliminate it or to see if that could be your problem. Anytime i scanning or diagnosing a problem with the jeep or chrysler transmissions i always look at and record the cvi values. Gary

Sorry for the delayed response, shop is crazy busy so my day starts at 330am


Sparkles
Novice

Oct 12, 2015, 6:30 PM

Post #18 of 19 (1798 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

K Gary, at the moment I'm at work for another 10 days (I work away from home), but as soon as I get home I'll get the CVI value on the Low/Reverse Clutch & others too. Post the results as soon as I can.


gsferraro
Veteran

Oct 13, 2015, 12:10 PM

Post #19 of 19 (1776 views)
Re: Trans shuttering (slipping in & out of gear) when coming to a Stop Sign In

ok sounds good






 
 
 






Search for (options) Privacy Sitemap