Hi all, 2004 FX4 with 108k makes whirring noise in 2wd and grinding in 4hi. Dealer says front diff needs replacement ($1400) and claims it probably wore out because I have different make tires on the front and back. (same size both with good tread left). Wants to sell me 2 new tires too. I only use 4wd in the snow when necessary, never on dry. I think he doesn't get it. Any opinions?

 

Saying "The diff wore out" is a pretty vague answer to the problem so yea I would definitely raise an eyebrow. Is he suggesting the entire unit needs replacing? They are repairable so replacing an entire differential seems extreme. Could be a bad pinion bearing or main bearings which can be done easily without replacing the entire unit. Also could be as simple as a bad u-joint, hub bearings, c.v joint etc. I'd get a second opinion from another shop/dealer.

 

yeah, he just wants to replace whole unit with a used/rebuilt which he couldn't even give me any details on. I think that's just the best moneymaker for the dealer. All they seem to want to do today is replace whole components.

 

108k is not a ton of miles so getting a used unit means it's probably going to have way more miles on it. A remanufactured unit is a different story but either way unless they offered one hell of a warranty with it, I would tell them to tell me exactly what the problem is and fix it. Not just throw used mystery garbage under my truck because they don't feel like doing a proper bearing job. (OR whatever the actual problem is). I don't know since I'm not looking at it though. They might have seen some major damage that warrants an entire replacement but they should have mentioned what that damage is exactly.

 

thanks Apexkeeper you pretty much summed up what my gut is telling me. I agree that if they saw major damage they would have said so and told me not to drive it home. And the business about the tires causing it seems far fetched. I guess I gotta talk to friends and try to find a reputable smaller shop-not that easy sometimes. I might try to get under there and have a close look myself but right now it's too effin cold out!