Novak Conversions Jeep Wrangler TJ radiator

42RLE shudder (torque converter?)

psrivats

runs loose!
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I have a 2005 TJR with 65k miles. Recently started hearing an intermittent "rattle" sound for a second or two when I am driving inside town. The noise occurs when the vehicle is well warmed up, as I am accelerating, and if I let off the throttle, and then get back on at very light throttle. The first time it happens is ~38-40mph, and happens atleast till 55-60mph (beyond which there is too much noise in the cabin to clearly hear it). The noise does not come if I give heavy throttle immediately after backing off. The noise is coming from the trans tunnel area, and sounds like a coin rattling in a can for a second or two. It is a very distinct sound and initially I thought it was something in my center console or toolbox, but I realized over time that it happens only under the specific conditions I described above. If I turn the overdrive off, this happens at a lower speed (starting from 25-30 mph) which was my first clue that this was transmission related.

I have checked that I have the right amount and right kind of ATF in the vehicle. Torque converter bolts are not loose. Haven't checked flex plate, but doubt if I have a cracked one.

For regular use inside the city, this noise is really annoying since it happens quite a bit as you are driving in just regular traffic. I was really going crazy and I did some reading and I found out that there are atleast couple other members that have reported the same issue. The standing theory that it is coming from partial lockup of the torque inverter. I still don't know if this is something that all 42RLEs do as they age - can folks with 42RLE chime in if your jeep has this kind of an issue?

If this is indeed lockup related, apparently there is a circuit fix to make the torque converter either fully locked up or fully unlocked. It seems crazy to me that you have to get to this level for a fix for this problem. I did find out that JKs with the 42RLEs have similar issue have a specific TSB to address this issue (that changes the programming in the TCM), but nothing similar exists for our TJs to my knowledge.

@mrblaine you have a lot of experience with TJs and these transmissions. Have you seen/experienced this issue in any of the jeeps you have worked on?
 
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  1. What is your tire size and gear ratio?
  2. What gear(s) are you in and what are your RPMs when the shudder occurs?
  3. What are your habits in regards to using the O/D switch?
The link to the A604 doesn't apply to our 42RLE and neither does the TSB for the JK. This is the 2003 Jeep Wrangler 42RLE Manual. The transmission is essentially the same but the 2003-2004 TJs still used a TCM that was separate from the PCM.

O/D Off = TCC lockup on 3rd gear
O/D On = TCC lockup in 4th gear

If overdrive is off before the transmission shifts into 3rd gear the TCC will go into full lockup as soon as the 2-3 shift occurs. If you continue to accelerate under moderate-wide open throttle, the TCC will unlock. If you cruise or slowly accelerate, the TCC shutter until you have enough speed for full lockup.
 
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I have a 2005 TJR with 65k miles. Recently started hearing an intermittent "rattle" sound for a second or two when I am driving inside town. The noise occurs when the vehicle is well warmed up, as I am accelerating, and if I let off the throttle, and then get back on at very light throttle. The first time it happens is ~38-40mph, and happens atleast till 55-60mph (beyond which there is too much noise in the cabin to clearly hear it). The noise does not come if I give heavy throttle immediately after backing off. The noise is coming from the trans tunnel area, and sounds like a coin rattling in a can for a second or two. It is a very distinct sound and initially I thought it was something in my center console or toolbox, but I realized over time that it happens only under the specific conditions I described above. If I turn the overdrive off, this happens at a lower speed (starting from 25-30 mph) which was my first clue that this was transmission related.

I have checked that I have the right amount and right kind of ATF in the vehicle. Torque converter bolts are not loose. Haven't checked flex plate, but doubt if I have a cracked one.

For regular use inside the city, this noise is really annoying since it happens quite a bit as you are driving in just regular traffic. I was really going crazy and I did some reading and I found out that there are atleast couple other members that have reported the same issue. The standing theory that it is coming from partial lockup of the torque inverter. I still don't know if this is something that all 42RLEs do as they age - can folks with 42RLE chime in if your jeep has this kind of an issue?

If this is indeed lockup related, apparently there is a circuit fix to make the torque converter either fully locked up or fully unlocked. It seems crazy to me that you have to get to this level for a fix for this problem. I did find out that JKs with the 42RLEs have similar issue have a specific TSB to address this issue (that changes the programming in the TCM), but nothing similar exists for our TJs to my knowledge.

@mrblaine you have a lot of experience with TJs and these transmissions. Have you seen/experienced this issue in any of the jeeps you have worked on?
Yes, and we solve it with a new torque converter.
 
  1. What is your tire size and gear ratio?
  2. What gear(s) are you in and what are your RPMs when the shudder occurs?
  3. What are your habits in regards to using the O/D switch?
The link to the A604 doesn't apply to our 42RLE and neither does the TSB for the JK. This is the 2003 Jeep Wrangler 42RLE Manual. The transmission is essentially the same but the 2003-2004 TJs still used a TCM that was separate from the PCM.

O/D Off = TCC lockup on 3rd gear
O/D On = TCC lockup in 4th gear

If overdrive is off before the transmission shifts into 3rd gear the TCC will go into full lockup as soon as the 2-3 shift occurs. If you continue to accelerate under moderate-wide open throttle, the TCC will unlock. If you cruise or slowly accelerate, the TCC shutter until you have enough speed for full lockup.

33/4.88 (thinking about 5.38s)
OD - I don't bother turning it off for the most part

I think the 1st shudder I see in my normal driving is when the vehicle goes into 4th gear - but only when I give it light throttle right around the shift point. With heavy throttle there is no shudder. What is surprising to me is that this is a more recent occurrence and I have been driving as I always have. Note that I have only 65k on my jeep and I have put close to 13k miles since I got the jeep and this was not there before.

Yes, and we solve it with a new torque converter.

Thanks Blaine and very interesting. I was thinking it might the TC clutch that needs replacement. Am I wrong in my thought process? What is physically happening in the TC that it needs replacing? Just wanting to learn. I can get mine changed if it will fix the problem. If you have a preferred part/brand, could you please share the details?
 
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Thanks Blaine and very interesting. I was thinking it might the TC clutch that needs replacement. Am I wrong in my thought process? What is physically happening in the TC that it needs replacing? Just wanting to learn. I can get mine changed if it will fix the problem. If you have a preferred part/brand, could you please share the details?
I neither know or care about the why or what. We had one with a very annoying shudder. Called my trans guy he said replace the torque converter and we did. Problem went away. I don't know the part # or the brand, he said you need a new one, I said send it. He did.
 
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I neither know or care about the why or what. We had one with a very annoying shudder. Called my trans guy he said replace the torque converter and we did. Problem went away. I don't know the part # or the brand, he said you need a new one, I said send it. He did.

Thanks. I will replace mine and report back.
 
Catalytic converter is fine. I had it checked. Also would not explain the very specific situation under which this happens.
Man bless you, you have worked hard on that Rubi and I’m under the impression it has been treated well. Keep your chin up.
 
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Kittens obviously. They become cats later.
Catalytic converters generally fail due to the matrix melting and breaking down into pieces which starts at the two small primary cats. The pieces clog up the secondary cat until the engine is unable to exhaust the combustion gases and RPM gets limited. I've never heard of or known anyone with the complaint of failing cat(s) causing a shudder in the trans.

Little known fact is the matricx is not ceramic based. It is a metal matrix of some sort that does not like to be removed from the shell. You see the comment, "just punch out the cat so it looks like it is still there". They don't punch out at all. You have to drill them into small enough pieces to pull out.
 
Catalytic converters generally fail due to the matrix melting and breaking down into pieces which starts at the two small primary cats. The pieces clog up the secondary cat until the engine is unable to exhaust the combustion gases and RPM gets limited. I've never heard of or known anyone with the complaint of failing cat(s) causing a shudder in the trans.

Little known fact is the matricx is not ceramic based. It is a metal matrix of some sort that does not like to be removed from the shell. You see the comment, "just punch out the cat so it looks like it is still there". They don't punch out at all. You have to drill them into small enough pieces to pull out.
We have a family here that has made millions extracting platinum from them...One problem here in the south east is getting a catalytic converter cut off your vehicle when you’re inside your home or a business. They pay pretty good money for them.
 
We have a family here that has made millions extracting platinum from them...One problem here in the south east is getting a catalytic converter cut off your vehicle when you’re inside your home or a business. They pay pretty good money for them.
Ya'll ain't special. Converter theft is up nationwide since the PGM shot up sky high. They do them in parking lots while folks are shopping around here.
 
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Ya'll ain't special. Converter theft is up nationwide since the PGM shot up sky high. They do them in parking lots while folks are shopping around here.
Well, what is different about us is when somebody cuts a converter off someone’s car they are glad about it.
 
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Ya'll ain't special. Converter theft is up nationwide since the PGM shot up sky high. They do them in parking lots while folks are shopping around here.

That same nonsense is happening all around downtown Portland as well. I used to love going there for coffee and people watching but now with the homeless situation, the crime, ugly graffiti and just how dirty it is everywhere it's just worth it. The last time I went 2-3mo ago to meet a friend for like an hour or two in the afternoon, and some tweaker broke a rear window glass in my XJ and stole a wool headcapa and a pair of gloves that were there on the rear seat. There was a nearby shop camera that caught who it was, but cops would not do anything about it. The guy just brazenly broke in on the middle of the day. People walking nearby didn't even miss a step. Had to pay out of pocket to get it fixed, ended up using glass from a junkyard vehicle.

IMG-20210118-WA0003.jpg
 
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We have a family here that has made millions extracting platinum from them...One problem here in the south east is getting a catalytic converter cut off your vehicle when you’re inside your home or a business. They pay pretty good money for them.
There’s been several arrests around my area for that in the last couple weeks.
 
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That same nonsense is happening all around downtown Portland as well. I used to love going there for coffee and people watching but now with the homeless situation, the crime, ugly graffiti and just how dirty it is everywhere it's just worth it. The last time I went 2-3mo ago to meet a friend for like an hour or two in the afternoon, and some tweaker broke a rear window glass in my XJ and stole a wool headcapa and a pair of gloves that were there on the rear seat. There was a nearby shop camera that caught who it was, but cops would not do anything about it. The guy just brazenly broke in on the middle of the day. People walking nearby didn't even miss a step. Had to pay out of pocket to get it fixed, ended up using glass from a junkyard vehicle.

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Wow. That's nuts. Takes balls to do that... Or knowing that no-one gives a rat's ass about catching them
 
That same nonsense is happening all around downtown Portland as well. I used to love going there for coffee and people watching but now with the homeless situation, the crime, ugly graffiti and just how dirty it is everywhere it's just worth it. The last time I went 2-3mo ago to meet a friend for like an hour or two in the afternoon, and some tweaker broke a rear window glass in my XJ and stole a wool headcapa and a pair of gloves that were there on the rear seat. There was a nearby shop camera that caught who it was, but cops would not do anything about it. The guy just brazenly broke in on the middle of the day. People walking nearby didn't even miss a step. Had to pay out of pocket to get it fixed, ended up using glass from a junkyard vehicle.

View attachment 242534
Portland sounds like ALL of CA. Our fearless leaders managed to get the felony threshold level raised up high enough that they police no longer respond to vehicle break ins, burglary, shoplifting and similar crimes. Folks on the local pages bitch about it all the time. We had some serious package theft well above the old felony level and they would not even send a cop out to take a report.
 
Portland sounds like ALL of CA. Our fearless leaders managed to get the felony threshold level raised up high enough that they police no longer respond to vehicle break ins, burglary, shoplifting and similar crimes. Folks on the local pages bitch about it all the time. We had some serious package theft well above the old felony level and they would not even send a cop out to take a report.

You absolutely hit it on the head. The police bureau here has other complicated problems going on as well. It makes me quite sad to see the slow ongoing deterioration.

Part of the reason I moved to this area was the "small big city" vibe. It's still kind of there but the past year had not been good in many ways.
 
Novak Conversions Jeep Wrangler TJ radiator