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Old 12-14-2020, 12:00 PM
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pizzaguy
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Default Re: Transmission FLuid, Differential Fluid at 100k Miles

Originally Posted by ABSAAL
Hello all, I recently received my Mom's 2004 Crossfire Coupe as a gift, and I love the thing. I have fixed countless issues on it through the great minds of this forum, but needed some advice
My car has 98,090 miles, and I wanted to do the 100k mile maintenance within the next month or two. My mom and I are am the second owner since about 60k miles.
1. I am not sure about the transmission history, but I know we have never changed the fluid. Is it advisable to do so now? It may be 100k mile old trans fluid. I don't want the transmission slipping.
2. Same thing with the rear transfer case. I am not sure about its history with the previous owner, but I know we have never changed it. Advisable to do it now at almost 100k?
3. I am going to do spark plugs and wires, but not coils as I have read on this forum that coils are a waste of money. I am looking at Bosch double platinum spark plugs and STI wires on fcpeuro.com. Are these good, or should I get something better such as Bosch Iridium? I have seen the stuff on Needswings, but personally don't like NGK and want to stick with Bosch. I have owned 4 Mercedes vehicles, and Bosch has worked great for each of them.
4. I am going to do a coolant flush with prestone long life. I don't feel like spending $20 on some specialty Mercedes coolant. Will Prestone do the job? Also, should i change out my thermostat as well for some preventative maintenance?
5. Anything else I should keep in mind?

Thanks!
1) Fluid and filter every 60,000 for an auto is my personal rule.
2) Did mine around 90,000 on the Graphite, came out smelling like tar - did it at 40,000 in my SE and 55,000 with my Ford Ranger. I used Mobile 1 75W90, took less than two quarts.
3) I ordered the cable/plug set Needwings sells. I've never bought a bad part from Rob and never had a 'fit' issue, either.
4) I would change the thermostat, but most don't. If you are not going to use the right coolant, just use 100% distilled water, does that work with your "feelings"?
5) Yes, use recommended fluids.