Somehow I have become the resident "car guy" at my firm. I was surprised when a few months back I got a call from our corporate Treasurer with questions about his 300SDL.

He told me the car had a noticable decrease in power, so he took it to the dealer. The dealer found a rag wrapped up in the turbo charger, which they claim ruined the bearing and turbo fins. It was probably left there by the dealership when they did the last tune up of the car, but (of course), the dealership denied responsibility. Regardless, he called me because he wanted to know what a turbo was and how a rag might have ruined it. I told him of my love for Mercedes Diesels and we became friends. The dealership replaced the turbocharger and it cost him $3,500.

Now this week he came to my office and told me the transmission seemed to slip once or twice when it changed gears on his way to work - like it was revving for a few seconds without the car accelerating. I told him to check his transmission fluid and he looked at me with a blank stare.

He loves the car, but he makes well into the 6 digits and he thinks it might be time for a new CDI rather than pour money into his beloved SDL.

He is the original owner. The car has been garage kept since day 1. The back seat has never been sat in. The oil has been changed religiously every 3,000 miles. It has 82,000 miles, and most were on the New Jersey Turnpike. It's smoke silver with tan leather interior. I have seen the car and it's about a 9.5 out of a 10. Absolutely no rust. Paint and interior are immaculate. Truly a spotless car, much bigger than the Mercedes diesels I am used to. He gets a consistent 27MPG, but has told me on occassion he gets into the low 30's if he drives less agressive.

He ofered to sell it to me since he feels I am "much more capable of maintaining it than he is". He told me he thought it was worth at least $6K, but told me to make him a fair offer.

I have no experience with the 300SDL's. I popped the hood and was surprised to find a 3.0L in-line 6 cylinder, (yes six) turbo diesel. I was expecting the 5 cylinder turbo diesel. This engine has an aluminum head instead of a cast iron head.

What do you think this car is worth?