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02 Jeep Liberty.... EXPERIENCED WRENCHES only need respond

Ok Ladies n gents… Im working on a friends 02’ Jeep Liberty. Here is the problem as I interpret it. As I drive this vehicle I believe I am hearing intermittent Clunks coming from the Xfer case…

As you drive this vehicle down the road you will hear intermittent clunking coming from the xfer case…its fairly pronounced. Im trying to wrap my head around the source of the issue. This owner does NOT use 4WD very often. However they do from time to time… The way the Liberty’s 4WD system works is as follows. The front differential is constantly spinning its driveshaft, there are NO WHEEL HUBS to lock…they are permanently locked and turning the driveshaft…the primary drive of this vehicle goes to or thru the rear diff so it is RWD until you lock the xfer case to power the front driveshaft. When you engage 4WD you are locking the xfer case into gear and thus now driving the front driveshaft as well as the rear.

My THEORY is as follows. Going INTO 4WD works fine…my idea is that it is not ENTIRELY DISENGAGING in the XFER CASE…This is where I believe the THUNKS are coming from…From the Xfer case partially engaging the front driveshaft intermittently. I can INDUCE MORE THUNKING sounds if I turn the front wheels HARD LEFT OR RIGHT.

What I need to know or rather RENFORCE in my head is this… DOES my front driveshaft increase speed when I turn the front wheels Hard left or right? WOULDNT IT THO? If the outer wheel in the turn must speed up…and the inner slow down…WOULD THIS NOT cause a difference in rotational speed of my driveshafts? I believe IT DOES…CORRECT me if I am wrong please.

If during a turn…my front driveshaft must speed up partially this would explain why I can hear MORE THUNKING during turns…because the driveshaft speeds are no longer equal as they would be driving straight down the road.

I BELIEVE that the Xfer case in this vehicle…which entirely controls the 4WD action in this vehicle is NOT FULLY DISENGAGING…For whatever reasons…These reasons, as I am learning are that sometimes Jeep Liberty owners say that they find that during a xfer case fluid change or check…THEY FIND THE XFER CASE DRY…EMPTY OF LUBE… If this is the case I can understand why I am hearing this CLUNK sound intermittently

Do ANY OF YOU GUYS have any experience with the Jeep Liberty? Have you ever heard of this before? I am a VERY experienced wrench myself so if you have detailed technical information…let it rip… I can handle it.

I think what I am looking for from experienced mechanics is as follows:

  1. Do you have any experience with Jeep Liberty 4WD?
    2, Do the front and rear driveshafts rotate at different RPMS during a turn (As I believe that they must temporarily)
  2. Have you heard of this “Clunking” issue from other Jeep owners or personal exp.? (the internet seems rather full of this issue) (Still looking for a solution)

Just need some info and tech advice and hoping some of you are familiar with the Jeep Liberty.

Blackbird

My '86 Cherokee had part time 4wd, with locked hubs and vacuum engagement for each wheel in the front axle. If it’s clunking going around corners after disengaging, it may have the same vacuum actuators that aren’t working.

Personally, I believe the answer to #2 might be no

I believe the driveshafts turn the same speed during a turn

It’s the differential’s job to make sure the outer and inner tires turn different speeds

The thing about the driveshafts is my opinion

Understood Texases…howev this system does not use front locking hubs… The front diff is permanently engaged… the x-over from 2WD-4WD occurs when you move the Xfer case lever into 4WD.

When in 2WD the front axles and driveshaft are constantly being turned by the wheels…when you engag 4WD the xfer case then transfers driven power to the front driveshaft…when in 2WD the xfer case lets the front driveshaft spin freely. I believe…if I was able to disconnect the front driveshaft from the xfer case…my clunking sound would Stop dead. I believe something in the xfer case is not fully letting go of the front driveshaft output…and when OR IF there is a difference in rotational speed of the driveshafts…we get more clunking naturally.

I still need people to second my theory that there actually IS a difference in rotational speed of the driveshafts…I believe that there must be a difference in speed of the shafts when in a hard turn…i could be incorrect however…So i need that question answered as well.

I am in process of changing the xfer case fluid…which turns out to be ATF+4 9602 type Auto Trans Fluid in there. What I drained out…did NOT SEEM TO BE ADEQUATE AMOUNT…SO the issue may be resolved right there… FINGERS CROSSED…UPDATE PENDING

Blackbird

Hi Honda
I cannot solve Your problem, but its the other way around unless it has difflocks:.

What I need to know or rather RENFORCE in my head is this..... DOES my front driveshaft increase speed when I turn the front wheels Hard left or right? WOULDNT IT THO? If the outer wheel in the turn must speed up.....and the inner slow down....WOULD THIS NOT cause a difference in rotational speed of my driveshafts? I believe IT DOES....CORRECT me if I am wrong please.
The car follows the front wheels. In a turn the rear wheels will turn in a tighter circle than the front wheels - short wheelbase, not so much, longer = more difference. The spidergears in the diff. for each axle will make the different rotations inner/outer wheel per axle into an "average". Then You'll have different speeds on the propshaft front to rear and, yes, they end up in the Xfer case so You are probably on the right track. Just remember that a clank or bang can easily travel through all that metal and give a wrong indication as to where the problem really is. I assume that You have checked the U-joints and the pinion bearings. Best of luck.

I must not have been clear - there were no locking hubs on the Cherokee, locking/unlocking was handled by vacuum actuators halfway between the front diff. and each front wheel.

Does it have the part time 4wd system?

edit - looks like Jeep got rid of the vacuum disconnect for the Liberty. If you have part time 4wd then the transfer box. may not be disengaging when you go to 2wd.

Im not actually sure about that Texas. It goes from 2WD…to 4WD Hi…and 4WD Lo. I know of those vacume actuators which you speak of…I do NOT see them on this vehicle.

Here is an interesting update however. I changed the Xfer case fluid…went for a ride…Clunking was there…and actually seemed even more present. SO…I sat with engine running and in Neutral…and moved into and thru all settings on the Xfer case…went for a drive…More Clunking. Did that over again with engine running and in Neutral…Same thing.

SO…I pulled over…put trans in Neutral…and shut the engine OFF… THEN…I Moved the Xfer case lever from Stop to Stop…Quickly and with Positive force. Did this about 3X from Stop to Stop…

Went for a drive…ZERO CLUNKING… Methinks my first theory was correct…the xfer case was sort of partially still engaged… It was only until i shut it down and cycled thru the xfer case lever settings HARD…From Engaged…to HARD DISENGAGED… Now it seems to be clunk free.

I am going to look for some sort of adjustment or setting attached to that xfer case lever…Maybe I can Adjust its Throw? Hmmm… For now…she seems positively Disengaged…Which is where I want to be.

From what I can tell…A LOT of other Jeep Liberty people would like to read this as I see complaints of clunking ALL OVER THE PLACE…

Blackbird.

There should be two manual actuators, one at the transfer case and one at the front differential. Full lubrication is essential for both to be operating properly otherwise, one will bind and you will not get complete engagement.

I’d see about lubricating the whole mechanism, and check for worn bushings/connections.

Dag, what actuator at the front diff? I found none on the exploded diagram.

In a turn the front wheels turn faster than the rear.

Jack up the front end and hold the front output shaft at the transfer case while rotating the left front wheel front to rear. Feel for play at the driveshat yoke at the transfer case. Driving on firm surfaces in 4 wheel drive severely stresses the system and the transfer case front output has appeared to be the weakest link in the system and first to fail for me.

I’m an old wornout wrench with some Jeep experience.

I’m by no means a Jeep guy but any chance this noise is related to a halfshaft binding? The Jeep is 13 years old.

The transfer case was not unlocking. The stress between front and rear driveshafts was causing the problem. You are right that the difference between front and rear wheel rotation causes the stress. On snow the tire slippage would not cause the noise. I ran my 4WD in a wet parking lot and the binding was really bad. I apologized to my truck for that.

The “ackerman principle” dictates that wheels follow different arcs through a curve-different arcs= different distances,on a fixed platform =different speeds(which is what the oldtimers called windup) without a center differential this is very pronounced,so everything is running in a bind when at 3 least of these wheels are trying to equalize in speed.especially pronounced on a 4wd with a LSD on drive pavement(which is one reason you dont want to run in 4wd on dry pavement with some 4 wds.My Dodge Dakota is almost impossibe to drive on curvey dry pavement in 4wd,especially when you are going above say 25 mph.The AWD systems on certain well thought out AWDs pretty much avoid these problems.
I would add that if this vehicle has a limited slip rear differential,make sure it has the proper additives in it-Kevin

As Kevin described, all four wheels will actually travel a different speeds in a corner depending on the arc they follow. The differentials, one on each end of the drivetrain, enable the inner and outer wheels to travel at different speeds while still transmitting torque to the wheels, and the transfer case allows the front driveshaft and the rear driveshaft to turn at different speeds while still transmitting torque (when in 4wd). The front driveshaft and the rear driveshaft will each be turning at the average speed of their respective inner and outer wheels.

However, there’s another compensating device: the front end has CV joints in the axles, three actually, INCLUDING one of the type that allows the track to change, allows the axle to change length (can’t think of the correct name for these). These do cluck when bad and under load and might also be making the clunking noise. They’re very easy to check and I’d make sure they’re good before tearing into the transfer case.

Just a thought. A quick check of the CV joints might, if they’re bad, save you a lot of expense and work.

EDIT: I still cannot think of the name, but it is this type of CV joint that I’m alluding to (see illustration).
http://www.bing.com/images/search?q=diagrams+of+types+of+cv+joint&qpvt=diagrams+of+types+of+CV+joint&FORM=IGRE#view=detail&id=45892835FE1492210336E126B66EC77A4C989C64&selectedIndex=1
In this diagram (attached) you can see it as the cylindrical assembly just inside of the rzeppa CV joint.

Hey Fellas…I am STILL trying to diagnose this. I found one important clue or at least I thought it was important. The Xfer case shift cable had a missing Grommet on the cables End…and Thusly was not moving the xfer case engagement lever as far as it should have been due to the cable end being very large and the shift lever end being narrow… The grommet filled in the space to make sure of positive engagement. I thought it would be problem solved…but I was incorrect.

I am definitely missing something here fellas. When I drive it down the road. In 2WD…I keep hearing the front driveshaft being partially engaged… It rings the front drive shaft like a bell. Ching-Ching…Ching…ching-ching-ching. I need to look into the front diff…what if there is a chipped tooth up there?

I tell ya…its an intermittent clunking, sortc of feels like the xfer case it not allowing the front shaft to spin freely all the time…and every so often it is hitting or trying to engage another gear as tho its not fully disengaged …its as tho it can spin but every so often its either trying to engage…or there is something broken flying round either in the Pumpkin or the X-fer case.

This is beginning to drive me nuts. I need some diagrams to see an exploded view of this system. Time to start looking for that.

Keep the thoughts flowing fellas…they are appreciated and I do try to suss each of your suggestions out. So the more the merrier, cause Im out of ideas…I thought that Grommet would have solved the problem, bec I thought I wasnt getting enough travel of the xfer case shift lever…which would explain my theory of not being fully disengaged. More ideas please fellas…Thank you

I’m going to have the front end up in the air and the wheels off today… Methinks I will be able to “see” or find out quite a bit while I do this…Its been CccOLD and wet here since I started this post. Not wet today…so Here goes. Will look into the Halfshafts…and prob disconnect the front driveshaft as well to see if that Fancy Pantsy Joint at the xfer case has not self destructed…I HAVE seen that before…As I just recalled seeing that previously. This is the expensive joint instead of the old tried n true U-Joint type.

Hmmm…I just may find something there now that you guys are jogging my memory. WHY wouldnt Jeep fully disengage the front driveshaft when not needed or in use… It is being spun/driven by the wheels CONSTANTLY while the vehicle is in motion…it NEVER stops turning. Its either being driven by the wheels…or powered by the xfer case…it never gets to STOP Rotating… SO YES…This could be an issue with one of the Shafts… Whether it be Half-Shaft…Drive Shaft…or SHAFT the TV show from the 70’s. I will let you know what I find.

Blackbird

Now that I am thinking about that Fancy CV type Joint at the front driveshaft…I am thinking that MAY BE the culprit…It might not be smoothly rotating and binding every now and again…thus ringing the front driveshaft literally like a BELL. If you tap the front shaft with anything…it Really does RING like a Bell. So I keep hearing this Ring-Ching ching ching…every now and again. It doesnt have a set or repeating pattern either…its random. YES…THAT JOINT IS NOW SUSPECT NUMBER ONE. Thank you guys…for giving me ideas.

Blackbird

These joints can wear a path (groove, if you will) in the area of the outer part where the planetary bearings on the yoke normally orbit, and when you turn the wheels and move the yoke out of its normal position, it can knock as the bearings fight to go back into the groove.

Hmmm I think I read you on this Mountain… Yes…this is possible. I’m sure I will discover all sorts of nifty things when I get the front end off the ground. Weather has turned NASTY with the Quickness As of Late…SO I havent even had the wheels off yet if you can believe that. LOL…That will happen today if time allows. I’m off to a job site to replace a Radiator in a Ford Explorer so my friend can actually drive his truck To n Fro work instead of getting a Ride and leaving the Explorer parked…LOL. After that mission I will work on the Jeep. But I promise I will look into each of the suggestions just to see what we get. Thank you again…

Blackbird.

I SOLVED THE PROBLEM!! I ALSO REALIZED THAT I AM GETTING OLD. I have solved the same issue on a Jeep Cherokee about 2 yrs ago…but I forgot all the details…I DID RECALL however what I did to fix it.

The CV style joint on the Xfer case for the front Axle is bad. It is binding intermittently…I should have remembered this from yrs ago…but I forgot.

I feel it is silly to have that front driveshaft turning constantly when you are not in 4WD…Its more wear n tear and its also more Rolling Resistance. Stupid actually…all so people dont have to get out of their TRUCK…and lock the Front Hubs.

I need to replace the front driveshaft CV joint at the xfer case. This is a common problem out there…because… on this vehicle the front driveshaft is turning CONSTANTLY. Thank you all for jogging my mind or memory with your suggestions

Blackbird.

Sincere congratulations, and thanks sincerely for posting back.
Many of us can sympathize with the “getting old” part, that’s for sure. Chalk up “one” for us old guys.