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In the process of changing my fluids and other vital components in my new to me 2001 C5. 70,000 miles. So far did the plugs, wires, O2 sensors, oil and scheduled the coolant change. Mechanic told me I should be ok to change the transmission fluid at 70,000, however higher mileage cars could cause problems over 100,000 with new fluid. Does anyone have an opinion on changing fluid at 70,000 miles before I touch it.
Bought my car at 84K....changed everything. On the trans I used Valvoline Max Life Synthetic. Changed oil and filter and welded a drain plug in the bottom of the pan. Two months later, drained the oil and refilled it again. No problems here......
Change the fluid yes. Pan gasket and filter too yes. Power flush the system NOOOOOO. If its an auto then by doing the filter and fluid you will get out between 1/4 to 1/3 of the fluid. Rest stays in the torque converter.
Royal Purple makes a darn good synthetic fluid. Good idea to replace, every so often. However don't know about A4's. I've run Mobil 1 ATF & RP SM(?) in my upgraded T-56's (Builder's Recommendation) - they worked like a charm.
Last edited by Hitman227; Sep 14, 2019 at 02:46 PM.
Reason: Question mark
Change the fluid yes. Pan gasket and filter too yes. Power flush the system NOOOOOO. If its an auto then by doing the filter and fluid you will get out between 1/4 to 1/3 of the fluid. Rest stays in the torque converter.
Thats why you drain it after a couple of months and refill. Then maybe in a year, you can do it again.......hence the drain plug.
Couple of things. Have them inspect the bottom T connector of the coolant reservoir tank. They break down pretty bad over time and if you are having coolant flushed, now would be the time. The Dorman replacement tank is about as good as it gets and comes with a cap.
On the transmission fluid, if the car was not abused, I would be shocked if it was bad. I changed mine at 100k and it was absolutely mint. There was one record of having it changed at 30k. I did the filter and Valvoline high mileage ATF, I would have no fear of changing it at 70k.
Just my thoughts based on my personal experiences.
All excellent suggestions. It's wise to keep the Fluids fresh.
Consider Power Steering componentry, consider differential option.
All Synthetic, the way to go.
Stay away from Amsoil Torque Drive. My car gets run HARD on road courses and autocross, so I figured Torque Drive was a good idea to upgrade the fluid. Its claims regarding temperature tolerance and lubricity seem great. I swapped it in and started having transmission temperature issues. My transmission eventually failed at Daytona this spring (not sure if it's related to the fluid, because there was some internal damage that probably wasn't a result of just heat). I had it rebuilt by Tick and put fresh Torque Drive back in it. I got transmission temp warnings AGAIN the next time I took it to the track. I contacted Tick and they told me that Torque Drive is a thicker fluid, and because if its thickness it has issues with fluid shear that leads to a rise in temperature in the fluid. They advised I switch back to non-synthetic ATF, which I did and haven't had problems since.