93 grandcherokee differential problem?

[donnabush]

Hi all,

I hope ya'll can help me out. I have a 93 jeep grand cherokee limited with 114K miles. It has a horrendous roaring noise under load. When car is in park and running it sounds fine. But, when in drive at around 25 mph and up there is a terrible roaring noise. I think it is coming from the front. It has progressively gotten worse and I am afraid the whole differential is gonna' disintegrate at any moment. One mechanic took out the drive shaft and says it is the front differential causing the problem and it could cost anywhere from $400 - $1000.
I have put so much money into this jeep over the last 2 years that I am reluctant to put anymore money into it. From reading some of the posts, it sound as though it could be the front differential, but it could be the transfer case or the VC. I hate to put a $1000 into the jeep only to find out there is another problem.
Can anyone shed any light on this problem? I would so appreciate it. And please forgive my ignorance about 4wd vehicles.
Thanks again,
Donna

[JDPascal]

Sorry for your vehicle troubles.

You might ask around for another reputable shop or mechanic and get a second opinion. No offense meant, but take a (male) friend with you who has some knowledge about vehicles. Even some reputable shops can weaken and prey on someone with less knowledge.

What is the vehicle worth on the market in your area?? Balance the cost of repairs against that value and decide where your point of diminishing returns is. Fix what you have to and move onto another vehicle if you can.

That also brings another set of unknowns with it though. Do you want to keep the devil you know or try a new one that will take a while getting sorted out too?????

Now, as to the problem you describe, yes it could be either of the two causes you mention.

Are there any unusual things happening when you turn a corner to enter a parking lot especially after a longer drive? If so there may well be problems in the transfer case/viscous coupler.

The 93-95 jgc's seem to have a reputation for transfer case and viscous coupler probems so if yours hasn't been replaced yet..................

Are there any leaks from the differential or transfer case? The first thing I think of in the differential that might cause what you describe is the pinion bearings.

If the differential just needs new bearings, your looking at about $100 for bearings and 4 hours or so for labour plus some oil and shop supplies and of course taxes. It just gets worse from there.

unusuall noises from those places very seldom mean good news.

JD

[ChadEbert]

Think JD summed it up pretty good. Ask around, call a local Jeep club and see who they recommend. Word of mouth means a lot. Good luck with it!

[donnabush]

JD and Chad - Thanks for your posts. I was thinking of trying to find a 4wd specialist in this area, if one exists. I trust this mechanic because he has worked on all my vehicles for the last 12 years, but I'm not sure how experienced he is with the 4wd stuff. It took them a long time to narrow it down to the noise coming from the front diff as opposed to the rear. I guess my biggest concern is that I put another $1000 into the vehicle and then the VC or the transfer case or something else equally expensive goes out. I've had it advertised for sell, starting at $3200, with only one person who called about it. I just parked it on a lot with $2800 OBO as the price.
Do you recommend taking out the drive shaft and converting it to 2wd? Or will that cause more problems? I seem to remember seeing a post somewhere that recommended against that.
I also don't know if I would be better off trying to fix the noise before trying to sell it. Do you think anyone would buy a vehicle with a roaring noise?
Also, JD, I have not noticed any difference in the noise when turning. Only noticed that it has progressively gotten worse. I was on crutches for 2 months and unable to drive. I only cranked it once a week and had a friend drive it occassionally. Now, it seems much louder and the check engine light stays on.
Thanks again for all of your help

[ChadEbert]

<Cringe> I'd try to keep it a 4 wheel drive. An idea: Try to capture at least half your losses and just sell it broken with it problem fully disclosed. Sometimes you just gotta walk away from these messes.

[YtseJam454]

If you are driving down the road and weave the vehicle Left to Right does then noise get quieter and louder as you maneuver it? If so you just need a hub bearing

[donnabush]

I drove the jeep this morning and tried weaving left and right. There is no difference in the noise. The noise only starts between 30-40 mph and gets worse at higher speeds. When it first started, if I backed off the accelerator, the noise would stop. Now, when I back off the accelerator, the noise continues for some period of time. I can also feel a vibration under my feet on driver and passenger side. The noise is less if I have the windows open as opposed to closed.
I don't know if that helps pinpoint the problem any better. I did find a Driveline specialty shop in my area. Do you think they would be better than a mechanic? Do you think taking it to a Jeep dealer would be better? Also, If I sell it, what do you think would be a fair price? KBB private party value for fair condition with some mechanical defects is $4700. The only other known problem is the headliner is drooping and 1 clip is missing from front bumper so it sags a little on one side.
Thanks again for all of your help.
PS. JD - I was not offended by your suggestion to take a male friend with me. I hate the way mechanics and car dealers treat women. Their behaviour is totally different if it is a man they are dealing with.
Thanks,
Donna

[xj31]

since you say the noise was related to stepping on the accelerator,it sounds like bad pinion bearings.

[ByronP]

If you have the full time 4wd(np249 transfer case) you CAN'T drive with the front drive shaft disconnected. This will cause the VC to overheat and malfunction. Though from the sounds of it I would have to agree about it probably being the front pinion bearings.
ByronP

[chutchin]

Donna,
I would definetely suggest you go to http://www.ineed1.com/quikmechanic.html.

They offer quick answers to car problems, at a cheap price of just $1. They helped me out when I couldn't figure out why my car temperature would rise when I come to stop, and be ok when driving. You'd think it would be the other way around, Anyway, I waste more than a $1 a week on junk anyway, so felt I could afford to lose it if anything. It's better than going some of those mechanic who tell you garbage, and charge you big money for nothing.

Good Luck,
Chutch

[cdlabelle]

Donna, Check out the following threads
...............grinding Sounds and
Weird Vibrations/grinding................your thread is the third with very similar problems, my 1998 GC Laredo.
(99,000 miles).
I'm 95% sure it,s the front differential bearings, like mine, and Ben's. When your mechanic took the drive shaft off, did he test the transfer case without it being hooked up to the front differential. If he did, i'll bet you there was no grinding.....