I would suggest getting a second opinion on that transmission work. If you've taken it to the "A" place, it's standard procedure to tell you that you need a new transmission. Try finding an honest, independent shop. Also, have you noticed any shifting or operating problems that actually feel like you need a new transmission? Beware of rip-offs. Now, needing to have a front differential rebuilt after only 50,000 is outrageous, unless the previous owner ran it dry of fluid or something. Same question--did the same garage tell you needed both things? I would suggest a second opinion in case you've become somebody's cash cow.
I have a 2003 Yukon XL with approx 48000 on the odometer. I've owned it since new. The SUV is comfortable to drive and roomy. Yesterday I took it in for its annual PA Safety Inspection and emissions test. The service consultant came out and said I needed new rear disc brakes and two new rear rotors. I physically checked this out and after looking at the rotors, they are actually deteriorating. Front rotors are also deteriorating on the inboard sides of all rotors. Front brake pads had 7/32 left rears were down to 4/32, with cracks and uneven wear due to the rotor problem. I've worked on cars all my life and have never seen a cast iron rotor deteriorate like this. Is this a manufacturing defect? Has anyone experienced this on there GM or GMC SUV? Normally front brakes wear out 2:1 to rear due to the power assisted front brake system. GMC says the rotors can't be cut and the flaking (deterioration is normal)?? I'm confused with that answer and do not agree with their findings.
I would assume that with 4-wheel disc brakes, the intent was to distribute the stopping power more evenly, so you may no longer have the 2:1 front brake wear, like with the older front disc brakes/rear drum brakes setup. 4/32"!? Wow, you were down to rivets! I don't believe that this is unreasonable or excessive wear if you've never replaced the brake pads in the 48,000 miles you've owned the vehicle. After all, this is a large vehicle with lots of momentum to get stopped. However, the warped rotors (were they warped, or was metal actually deteriorating off the rotors?) could be a result of not having the brakes serviced before now. To tell the truth, 48,000 miles between brake service sounds like too much to me. Did you really mean that the rotors cannot be turned down smooth? I guess I never heard of a brake rotor that could not be machined. Is this just a ploy to make you spend $1,000 on new rotors? If the rotors are undersized for the vehicle, you may be able to obtain aftermarket discs that have been crossdrilled to dissipate heat more efficiently.
I bought a 2003 Yukon XL in '06 with 70K miles. I've had problems with rear heater, windows, rear wiper, light sensor, left signal, second row seat belt locking up, rear door latch.
I bought the extended warranty, only for none of these problems to be covered. If it wasn't for the local dealer I bought it from, I would have gotten rid of it already. Some of the problems had to be corrected twice.
I checked Consumer Report's 2008 book and they say the 2003 GMC Yukon XL is a worst buy.