Jeep *******

I took my Jeep cherokee in recently to Jeep Bryanston to replace an oil pressure sending unit. Started as a R1500 job and ended up being around R6k. I conceded and paid for this as we're out of warranty, fine. Then when collecting my car once this job was done, literally driving off the dealer floor from this fix, we get an error that was not there when we took the car in. This one said 4wd system unavailable. Long story short after several days of testing etc., they tell me they must replace the power transfer unit. Around R60,000 that I must pay because its out of warranty. My argument is that this was not an error when taking it in there, yet something that occured while with them. Of course they defend this saying its totally unrelated. Why should I now have to fork out R60,000 to get this fixed? I explain my position to both the mechanic and the service manager saying this is not acceptable and they must make good and sort it out, failing which I will consider going legal and take this nonsense experience public. Does the service manager then not threaten to sue me if I try?!? Telling me he understands I'm frustrated but they also have lawyers etc. Unbelievable! Where is the commmon sense here.