Apologies upfront as I am not automotively inclined! I have an 04 automatic Sub Forester w/ ~79,000 miles on it. At ~ 34,000 miles (before the warranty was up) I noticed a clunking/grinding noise when I turned to the left at low speed, like turning into a parking spot. It only happened when the car was warm and had been driven for at least 15-20 minutes or so. A couple thousand miles previously, I did put one new tire on after getting a flat. The other 3 tires were pretty new and the tire dealer said it would probably be ok b/c the difference in tread between the new and old tires was < 1/4". After I noticed the noise, I took the car into my Sub dealer, as well as a trusted independent mechanic, who both could not recreate the noise. So, I’ve been driving it without problems ever since, but I have noticed the clunking/grinding noises now occur when I turn right at low speeds, again, I haven’t experienced any other problems with the car. I’ve been doing some reading on this forum and others and it sounds like I might have a problem with my center differential? Could this be the case even though the new and old tires were within the recommended range? The car was stolen (before the single new tire was put on) and out of my possession for ~ 1 week. It was found intact, although the thief was in the process of removing one of the tires when he was caught.
My questions are:
1) Does it really sound like the center dif?
2) How much will it cost to repair? Can I ask for used parts?
3) Since I noticed the noises and took the car into the dealer before the warranty was up at 36,000, could the repairs potentially be retroactively covered by the warranty?
Thanks in advance for any help!
Automatic or manual transmission?
There isn’t really a center differential on an AWD Subaru. The old 4WD cars may have had one, but the AWD cars don’t.
The manual transmission cars use a viscous coupling to link the front and rear drive axles and allow for slippage when necessary to prevent binding.
The automatic transmission cars have a hydraulically activated transfer valve and clutch pack in the rear of the transmission. Drive is always provided to the rear axle, but the valve reduces pressure on the transfer clutch as the steering wheel is turned to prevent binding between front and rear.
I suggest you have the transmission fluid and the differential fluid changed. This may help reduce the noise.
If your car has an automatic there should be a FWD fuse receptacle under the hood. Inserting a fuse will disable the rear drive. If the noise goes away with the fuse inserted you can be pretty sure the problem is in the transfer valve and clutch pack.
Having mismatched tires on a Subaru is never a good idea, and it WILL lead to problems, especially on the automatic transmission models.
When I had the transfer valve and clutch pack replaced on my Legacy (mismatched tires installed by previous owner) it cost me approximately $750.
Good luck.
You could have a worn out CV joint. Those car thieves are not known for good driving habits. Either way, somebody else may have to try to solve the problem.