Shortly after receiving my car back from service (replaced a shift fork in my transmission) I heard what I thought was the infamous transfer-case "death whine." After looking at the invoice for my transmission repair, I saw they put some different GL4 fluid into my transfer-case (was NOT the part number for DIAQUEEN). Adding 2 and 2 together, I thought I had it pinned as the transfer-case and thought it was THEIR fault after using the wrong fluid.

To make a long story short, I brought my car in for diagnosis, and lone behold, it is actually the rear-differential? What could cause the rear-diff to fail? I haven't heard of many going "bad?" The fluid was replaced at 3k miles with DIAQUEEN, other then that, it was untouched.

The dealership is going to cover it (they said this is my last repair before my car is "red flagged." Yeah... We'll see about THAT!). Unfortunately, there are "none in the country" and apparently they have none available in Japan either, as they gave me a tentative date of "THE LAST WEEK IN NOVEMBER!" (2½ months from the point I brought my car in) WTF?

 

Call Jon at TRE. Depending on what exactly is wrong with it he may be able to rebuild it for ~ $400.

Or if you don't want to wait you could look for a used rear diff on here. I picked one up last year with a couple thousand miles for $600.

EVOlutionary

 

Thanks for the advice, but the dealership is covering the rear-diff replacement. I was curious as to what can cause such a failure moreso than finding a replacement.

I am assuming it is a bearing, given it is a "whining" noise that changes pitch with the speed of the vehicle.

 

Actually, that sounds more like worn gears to me. Hmmm. . . let us know what they find out it wrong with it.

I was just saying if you don't want to wait 2 months you have other options. I know I couldn't be without my car for that long. Hopefully they are giving you a loaner car to drive.

 

Why do i have a feeling it's the t-case rather than then rear diff.

G.luck

 

i also think its the transfercase and not the rear diff. The noise of a whining transfer case can resonate down the driveshaft making it seem as if its coming from the back .

 

Actually, they told me to keep driving it because they needed their "loaner car" for other customers. They said driving it around would be fine, it could only get louder in the meantime while we wait for the rear-diff to come in.

 

These were my thoughts exactly, but they were persistent that it was the rear-diff and not the T-case. They said they used a stethoscope to verify the diagnosis. I am still skeptical, I think they MAY be covering their @$$ for putting the wrong fluid into the T-case (my diagnosis based upon the invoice I received back after my tranny warranty work).

 

So they diagnosed a broken or worn out rear diff just by it being noisey?? That's BS. Did they even check the gear lash/free play as the service manual says? Did they take the rear diff apart to verify the ring and pinion are worn abnormally or cracked??

This is just another case of a dealership wasting Mitsu's money on bogus warranty repairs causing the price of all of our next cars to go up . . .

 

Good question, I don't trust them, but what am I going to do? If I were paying for it, it would have gone to TRE or Shep.

 

Even with a mechanics stethescope its not that easy to pinpoint the sound. I remember reading a post while back where a member took his evo to the dealer for a whining noise and they would up changing the rear differential and driveshaft because thats what they though the noise was coming from but turned out to be the transfercase and it wasn't until they changed that out that the noise went away.

 

I've thought about this as well, and figure when they replace the rear-diff and that isn't it, then I will have a complete new drivetrain and can tell them "told ya so!"

 

********UPDATE*************

So, they replaced my rear-differential and sure enough it DIDN'T GET RID OF THE NOISE. They are now leaning towards the driveshaft or carrier bearings? I told them it was the transfer case from the very begging, not only have they made me wait 2 months, but they did not fix anything!

 

I would bet money it's your wheel bearings in rear.I just repalced wheel bearings in an VIII that the dealer repalced transfer case and rear diff assembly.

 

I've never heard a wheel bearing make this howling of a noise, wouldn't it be more of a vibration/grinding sensation? Also, this noise does not change based upon load on the left and right side, you can usually pin point a wheel bearing by swerving the car and determining whether it changes pitch or not. Just my thoughts.

This noise sounds like a textbook transfer case "death whine."