Jeep Garage  - Jeep Forum

Jeep Garage - Jeep Forum (
-   Grand Cherokee - WJ (
-   -   2wd wj (

Cherokeep 05-13-2012 09:05 AM

2wd wj
My question to the JeepGarage brains trust, Can you disconnect the front tailshaft and essentially drive the jeep as a RWD?

The reason that i am asking is that i am fairly sure through extensive forum trawling that my front yoke bearing is buggered.
My jeep makes a nasty whine under acceleration, the noise comes from the front, increases in pitch as road speed increases, temporarily quietens when going over a rise or dip in the road.
Also, there was a small amount of diff oil leaking out of the right hand side of the front axle, before the CV boot, fairly sure it was diff oil from "the ol' stick ur finger in it and smell it" trick.

I also think it could be a wheel bearing, i jacked the front up and rocked the wheels 12-6, 9-3 oclock and one had a tiny bit of play.

However, when i think about disconnecting the tailshaft, i start to wonder if the quadra drive system will try to send power to the front under normal driving conditions and just spin up, causing wear and affecting drivability.

This thought is ONLY to attempt to reduce damage to the vehicle, get rid of the noise for the time being, while i source some parts and attempt to rectify the issue properly.

I will probably try and take the tailshaft out anyway and see what happens when i drive it up and down the street. If it acts funny in any way i would not try and drive it for any length of time.


Frango100 05-13-2012 09:43 AM

Re: 2wd wj
You have the 247 T-case under your jeep, the same as i have on my Quadra Trac II. There is no problem in removing the front propeller shaft and drive around as a 4x2. Due to the fact that the shaft is removed, the progressive coupling inside the T-case will be activated, trying to transfer power to the front shaft, but the output will just freely rotate. The rear propeller shaft is always directly connected to the T-case, so all power will still go to the aft wheels. I drove around like this for some weeks, waiting for a new propeller shaft aft CV joint to come in.
Regarding the fluid coming out of the diff tube, thats probably the seal, which is placed from inside the diff casing. Quite some work and special tools needed to remove the diff case out of the diff. With the front joke bearing you mean the pinion bearing, which is coming out of the aft side of the diff? Also check the diff fluid level, since it seems to be leaking, it can be low on fluid and cause noises. Take care to not continue driving around with a low level, it will damage the bearings and/or pinion/ring gear.

Cherokeep 05-13-2012 09:59 AM

Re: 2wd wj
Wow mate thanks a lot for your reply, very informative :)

I will happily go ahead and remove the tailshaft, however some follow up questions.

If the noise remains as normal after removal, does that discount the yoke/pinion bearing of being at fault and therefore a wheel bearing is more likely the culprit?

I have some diff oil to put in, i will also do this asap as a deterrent of further damage.

With the seals inside the diff housing, could you clarify what special tools are needed, i have a very adept mechanic offering to "tutor" me as i do the work myself at his workshop, however he does run his own business and will be preoccupied most of the time. So i have access to general workshop tools.

thx again

Frango100 05-13-2012 12:58 PM

Re: 2wd wj
You have a good change that if the noise stays the same, that the problem is a wheel bearing or a drive shaft CV joint. Are the rubber boots from the CV joints ok? Don't know which setup you have on your WJ regarding the front propeller shaft. There are or 2 CV joints or 2 U-joints in it. When you have the propeller shaft out, check those joints for play as well, you never know.
Regarding the special tools needed for removing the diff case, there is a special spreader needed, which will spread the diff casing a bit, which is necessary to remove the case. Never done this myself, so can't tell you if you would be able to remove the case without using the spreader. There is some other special tool for the removal/install of the seals, but i think that you could use some alternate ways to do that.

Cherokeep 05-15-2012 05:17 AM

Re: 2wd wj
Ok front prop shaft removed (easier than i expected, 12 bolts), Noise has completely gone, and i can now hear the mud tyres flapping around on the road at speed :D:D

Does this narrow the issue down to the diff itself or a bearing inside?

On a side note, i am gettin 30l per 100k (or 7 mpg), i have cleaned the throttle body, changed engine oil, spark plugs. What am i looking at next? O2 sensors? I am just trying to tick things off the list of possible causes.

Frango100 05-15-2012 05:47 AM

Re: 2wd wj
If you have a scanner which shows live data, you could monitor the O2 sensor ouput voltages. They should vary a lot. When they stay fixed or only vary a little, they should be replaced. Also good to check the fuel pressure at the rail.
How is the acceleration of the jeep, firm or sluggish? A (partly) plugged silencer could also be your problem.
Also when not checked yet, have a look at the air filter.
You know now that the wheel bearings are ok, there still is a change that the drive shaft CV joint is the problem. Did you check the CV or U-joints on the propeller shaft? They should be completely without play.
You have a big change that the problem is inside the diff however. I would drain the fluid and check for metal glinsters in it.

Cherokeep 05-17-2012 06:42 AM

Re: 2wd wj
Is there any other way to drain the diff fluid than to take the diff cover off?

The front prop shaft did not seem to have any play in it. To check the wheel bearings is that the method of "shaking" the front wheels when theyre off the ground and feeling for play?

For the fuel economy, my air filter is clean, the car does not feel sluggish (atleast i dont think it does, its my first jeep and first v8, i am very happy with the power atm so if its running sluggish i will be SO HAPPY to get it running better) but it does feel like its driving normally, just bad fuel economy and black smoke under acceleration.

I got these codes when i did the key dance; 1281 0171 0137 1685

Googling these points to an O2 sensor, is it possible to take them out and clean them up before deciding that they require replacement?

Scanners are really expensive arent they?, also, how would i check the fuel pressure at the rail?

All times are GMT -5. The time now is 12:31 AM.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community