Cadillac Repair: 1998 deville outside temp, auto parts store, rear seal

Question
Hi, I have a 1998 deville and recently the outside temp has been reading extremely high, ( for instance its snowing out and the car says its over 120 ). Also when this is occuring the heating system doesnt operate correctly, i.e. it never warms up unless you turn the setting up to 90 where it always stays on.  Any Ideas on  how to fix it?  Also, on a recent tire purchase the store i went to quoted me for a repair, i was wondering if you could clearify for me maybe what part they are calling for to replace since i cant locate it myself, even on gmpartsdirect.com.  The quote says "replace rt rar spindle" and the price of the part is 686.04.  When talking to the associate he claimed that it is some sort of rear seal that goes bad and will cause the tires to wear premature. He said it is a common cadillac issue of the period.  Any help is greatly appreciated.

Answer
As to the outside temp sensor you can easily replace it yourself in about 20 minutes. If you E-mail: Cadillactech@hush.ai and he can provide you with a picture and directions on how to replace it.

As to the right rear spindle, they are most likely referring to a faulty HUB BEARING which is goin bad and the hub and bearing come as an assembly and you can get one at most any auto parts store.