Rumble Strip Noise

[FMfm]

My 07 Liberty Sport makes a sporadic noise typically between 40-50 mph. When it happens it's only for a few seconds and it just like driving on a rumble strip although not as loud or severe. I thought it might be u-joints on the rear drive shaft. The rear joint felt a little stiff so I replaced it but it still makes the noise. The problem is that it is sporadic. I drove it 60 mile the other day and it didn't do it at all. Then I went on another trip 20 miles one way and it did it twice in the first 10 minutes and then not at all the rest of the way there and back. My wife is the primary driver and I don't want her getting stranded somewhere. What else could be causing this? I don't feel any play in the flange on the pinion shaft at the rear differential. I did have to have the pinion seal replaced last summer because I noticed oil dripping on the garage floor. Could it be one of the cv joints on the front drive shaft? Sporadic malfunctions can be difficult to diagnose and I would like to avoid expensive trips to a mechanic if possible. I can do most R&R type repairs that can be done with basic hand tools. Any advice would be appreciated. PS it has 52K miles on it.

 

[Cardhu]

http://project-jk.com/images/tsb/TSB_21-002-07-REVB.pdf

Project-JK.com - Jeep JK Wrangler Resource » TSB - Flash: Torque Converter Shudder / Shift Quality Improvements / DTC P0732 - REV. B

Check your build date on your door sticker and see if TSB applies.

 

[FMfm]

Thank you. It sounds like torque converter shudder just might be what it is. I have to call home and ask my wife to get the date off the door sticker for me. Do you know if this is something that might be covered under warranty? I'm not sure if 07 liberty has 7yr/70K mile powertrain warranty or not.

 

[FMfm]

http://project-jk.com/images/tsb/TSB_21-002-07-REVB.pdf

Project-JK.com - Jeep JK Wrangler Resource » TSB - Flash: Torque Converter Shudder / Shift Quality Improvements / DTC P0732 - REV. B

Check your build date on your door sticker and see if TSB applies.

I checked the build date and it does apply, that's the good news. The bad news is that it looks like the torque converter has to be replaced which won't be cheap.

 

[FMfm]

One more question. Should I just run it with the OD disabled until I can get the torque converter replaced? Is there any danger in driving it like it is?

 

[Cardhu]

describe when it does it. shift from 1 -2, bottom of 3rd gear, only in reverse, with 4wd part time on, etc?

are you lifted, do you have bigger tires, does this tsb even apply to your vehicle?

If tsb is outside your build dates....

Have you or the previous owner ever service the trans, does it have the right fluid and no additives or magic fix-all fluids that are not ATF+4?

Lots of things to check before you start ripping transmission out to replace TC. Replacement gets pricey especially if it isn't your problem.

 

[FMfm]

describe when it does it. shift from 1 -2, bottom of 3rd gear, only in reverse, with 4wd part time on, etc?

are you lifted, do you have bigger tires, does this tsb even apply to your vehicle?

If tsb is outside your build dates....

Have you or the previous owner ever service the trans, does it have the right fluid and no additives or magic fix-all fluids that are not ATF+4?

Lots of things to check before you start ripping transmission out to replace TC. Replacement gets pricey especially if it isn't your problem.

The vehicle is completely stock including tires. I had a complete 4x4 service done in July with all fluids changed in ******, xfer case and both differentials at the same time when I had the pinion seal replaced. I had that work done by a qualified mechanic so I hope he put in ATF+4. I will check with him when I see him Monday. We have owned this vwhicle since new and there are no additives. The shudder typically occurs early in the trip at the speed when it shifts into overdrive. It seems not to occur after it has been driven more than 15 minutes. When it does occur it is sporadic. It has occured twice in one trip for me and as many as 3 x in a trip when my wife was driving it.

 

[Cardhu]

I had that work done by a qualified mechanic so I hope he put in ATF+4. I will check with him when I see him Monday.

Start there with the ATF. If it is anything but ATF+4, you need a full flush to get whatever might have been put in out.

Mine is outside those recall dates but still get some shudder intermittently.

Some of us get the shudder even when stock at the bottom end of 4th when the engine revs are low and it lugs along when coming up a hill.

I sometimes get it at the bottom of 3rd now that i'm stock geared with 245 75 16 decreasing my engine rpms at that speed when it wants to shift.

I keep OD off period when running below 90km/h as i think it its a dog with the bigger tires. slight increase in speed and it all goes away.

If it isn't related to your engine rpm and gear choice then there are other things to consider.

 

[JeepJeepster]

I was driving an 06 work kj the other day and it did something odd like that. Speed was around 45-50 and the rpms dropped to around 1k. The entire jeep shook then it downshifted and all was well. Think it has around 100k on it and no fluids besides the engine have ever been changed.

Does your rpms drop when that happens? Like its upshifting to soon?

 

[Cardhu]

mostly when your lugging along and pretty easy on the gas. I haven't noticed anything other then it bogging down when trying to accel out of too high a gear together with a small stumble. I believe my issue is related to needing to regear (numerically higher) which would in tern move my rpms up to where the engine makes enough power to not be a dog at the bottom of a gear range in terms of speed required to enter 4th or 3rd as noted in my case. Prior to new larger tires, it only existed on the 3 to 4 upshift at around 80 km/h; its just not happy at sub 1500 rpms.

If your speedo is not reading correctly you can also experience this as your shift points for you AT will be off dropping engine rpms to the lower power range for the indicated speed effectively short shifting aka falling on its face and letting you know its not happy.

The summary from all those that have regeared is that even though their rpms are higher it does not translate into increased fuel consumption and makes the engine work in the happy range with increased power and ability to deliver it to the ground. Higher rpms at highway speeds are also beneficial when pushing something with the aerodynamics of a toolshed at highway speeds. I probably don't need to dwell on added rotational weight of heavier / larger tires and what those implications are.

Stories of those running stock gearing and 32s 33s and abysmal fuel millage becoming the norm reinforce this. Similar for those that run 32s on the manual (3.55 rear) and can't use 6th anymore as the revs are too low unless downhill with wind in back.

Somewhere there is a HP torque curve that shows how little power is created near 1000 - 1300 rpm vs 2K vs 2300.

I find 245 75 16 bearable with stock gearing but far from optimal even in absurdly flat Manitoba. I would have prefered 255 70 16 instead if you find a tire choice you like with stock gearing.

nb: I think i drifted in my thought when writing this but its a summary and felt compelled to finish it. It also assumes your transmission hasn't been cooking fluid for 6 months consecutively/ using the right fluid. The verge of reagearing as noted in the tire section is pretty much bang on by experience.

to the OP.
your stock geared and stock diameter tires, this isn't your issue.

TLDNR: Yes i think it upshifts too soon.

 

[Luke]

...when pushing something with the aerodynamics of a toolshed ...

:happy175:

Ahhh I needed that .. thx

 

[TwoBobsKJ]

I find 245 75 16 bearable with stock gearing but far from optimal even in absurdly flat Manitoba. I would have prefered 255 70 16 instead if you find a tire choice you like with stock gearing.

Cardhu, I have 255/70-16's and I will be regearing to 4.10's soon. I have the front diff from a 4 cylinder KJ under my workbench. Still trying to find a shop I trust to regear the rear end.

The engine just lugs too much for me - and my highway mileage has gone to crap with the bigger tires and lift. And towing would be better with lower gears - the ****** just wants to upshift too soon with the 3.73's and bigger tires. All of which puts too much stress on the ******.

Bob

 

[FMfm]

The vehicle is completely stock including tires. I had a complete 4x4 service done in July with all fluids changed in ******, xfer case and both differentials at the same time when I had the pinion seal replaced. I had that work done by a qualified mechanic so I hope he put in ATF+4. I will check with him when I see him Monday. We have owned this vwhicle since new and there are no additives. The shudder typically occurs early in the trip at the speed when it shifts into overdrive. It seems not to occur after it has been driven more than 15 minutes. When it does occur it is sporadic. It has occured twice in one trip for me and as many as 3 x in a trip when my wife was driving it.

Here is an update. Back in November I had the torque converter replaced and the computer reflashed as per the Chrysler service bulletin. It ended up costing me $900. It ran fine until this past June when with no warning the ****** failed. That time it cost me $3500 for a Jasper reman. That was at 56K miles. I am sorry I purchased this vehicle. There is no reason for such catastrophic failures on a vehicle that was never abused, never was off road or in mud and had all proper maintenance done. This is the fourth Jeep we have owned and unfortunately will be our last. With Chrysler now being owned by Fiat I see no future for this brand. Too bad.

 

[dude1116]

Here is an update. Back in November I had the torque converter replaced and the computer reflashed as per the Chrysler service bulletin. It ended up costing me $900. It ran fine until this past June when with no warning the ****** failed. That time it cost me $3500 for a Jasper reman. That was at 56K miles. I am sorry I purchased this vehicle. There is no reason for such catastrophic failures on a vehicle that was never abused, never was off road or in mud and had all proper maintenance done. This is the fourth Jeep we have owned and unfortunately will be our last. With Chrysler now being owned by Fiat I see no future for this brand. Too bad.

Sorry to hear. Did you ever have the ****** serviced? If so, where? If it wasn't the dealer...that could have been the very issue.

Honestly I never understand why everyone bashes Fiat. They're one of the most successful motor vehicle companies in the world. Clearly they're doing something right...

 

[Hedsic]

Mine does this every once in a while. It's usually when I am slowly accelerating to speed not doing a quick acceleration. nothing changed on RPM's and it doesn't bog down. Does it very randomly so I haven't been able to replicate it when actually needed. It's been that way since before I got tires/lift etc.

I just assumed it was one of those things Jeeps do that you get used to over time so I never gave it much thought.

 

[ionizer]

mine too..... used to it. lots of kms. started at about 200 000 k. I just dont drive it gentle anymore, and it happens less.

 

[tommudd]

These things like to be ran, engines and trannys
Like I have said countless times mines at the limit at least once a day and its still holding together at 192,000