I was just wonering if it is good or bad to change the tranny fluid it has close to 200000 miles on it. I have heard that is bad but I dont know??? What do you guy's think.thanks. and I was also wondering about a boost controller to are they helpful to get more boost?? and where can i get one? what do you guy think about a underdrive pully?

 

How does the fluid look? Is it black and burnt smelling? At 200K I'm not sure I'd want to mess with anything. I'd certainly not be looking for more boost unless I was confident the engine was in tip top shape form a mechanical and maintenance perspective. But that's just me.

 

Concur... Check the color of the trans fluid. It should be clear and red to slightly pink. I have a 95 850 Turbo that had 170K on it when I got it and the fluid looked the color of used motor oil!!![:'(] It took me 18 quarts and several fill/drain cycles, but I finally got it so it now has clean fluid. Tranny shifts MUCH better now.

So, in my humble opinion......Change it!

 

I changed mine at 132K and so far so good. FWIW, I went the drain and refill route too rather than a flush.

 

I have a 95 850 T5-R. Just had some work done at local dealer. They suggest flushing tranny fluid every 25000-30000 miles. He said the tranny will last forever. It's $195. A guy at work just had his 93 850 tranny fkushed and he said it shifts much better now.

 

At 200K miles, it will be black. I would not power flush, in fear that debris will break loose and cause problems.

Here are procedures that I used to drain and fill...

https://volvoforums.com/m_25657/tm.htm

 

I have a 95 Volvo 850 Turbo that I purchased in 2001. I had the transmission flushed and since then I have had it drained and refilled every two years. Transmission is tight. I would definitely have it flushed if you plan to keep the car.