Hyundai Repair: 2002 santa fe front diff noise, differential problems, differential assembly

Question
QUESTION: Hi, I have just bought a 2002, 2.7 santa fe with a very noisy diff, well the noise seems to be coming from there. When driving the car the grating/grinding noise gets louder as you speed up so I've only done 20mph. Can anyone tell me if this a common fault or perhaps the fault is not the diff but something else. I have not had the car in bits yet I was hoping that someone might be able to point me in the right direction first. Regards Phil.

ANSWER: Hi, Phil.  I've seen very few Santa Fes with rear differential problems, but many with transfer case problems.

I'd recommend running the car on a lift and listening for the noise so that you can pinpoint it prior to doing any disassembly.  This way you at least know you're disassembling the correct component.

---------- FOLLOW-UP ----------

QUESTION: Hi, sorry I did not make it clear that the noise was coming from the front. The previous owner had it on ramps and thought the noise was the front diff. But then he wanted to sell the car and I took the gamble. So it's probably the transfer box is it? Can you advise on repair times and costs. Any help would be appreciated. Kind regards Phil.

Answer
No problem, Phil.  

If your Santa Fe is 4WD, the transfer case bolts onto the transmission right at the differential assembly.  It'll be important to test the vehicle on a lift to verify whether the noise is coming from the transmission or transfer case.  The transfer case is indeed the more common failure.

If it's front wheel drive only, you don't have a transfer case, and if you're sure the noise is coming from the differential, you should probably plan on replacing the entire transmission assembly as the front differential is part of the transmission.  Even so, I'd still recommend running on a lift just to verify it's not a hub bearing issue.

Expect about 12.5 hours labor to replace a 2WD transmission, 15 hours for a 4WD transmission, and about 9 for a transfer case.  Parts price for a remanufactured transmission is about $1000 to $1500, and if my memory serves, the transfer case (no factory reman available) is about $3500.

In any scenario, it'll pay to be sure it isn't a hub bearing.