2000 Ford Mustang, V6, base model, with manual transmission, 160K+ miles. Owned since new, drove first 10 years as daily driver. I’m thinking of changing the power steering fluid, which has never been changed. The fluid is Motorcraft MERCON ATF. I'm told this fluid is no longer made, and the replacement is MERCON V ATF (part no. XT-5-QMC).
However, the owner’s guide says MERCON and MERCON V are not interchangeable, and cautions “DO NOT MIX”. The owner’s guide is 20 yrs old. I’m not aware of any updates. Does the old warning apply with the new MERCON V? To be conservative, I would need to thoroughly flush the entire system, somehow. Instead of that, I would like to use the “turkey baster” method, which leaves a small amount of the old fluid mixed with the new. What should I do?
The power steering system has never leaked and works with no issues. They say if it ain’t broke don’t fix it. In the future, if the fluid level did drop a little and I needed to add something, I would be facing the same question.
Ford has not addressed this question, as far as I can tell. This is not the first time Ford has changed fluid specifications, without notification to the owner. They changed the oil specification for the engine from 5W-30 to 5W-20, but I only learned of that when I had a dealer change the oil, and noticed the invoice did not match what the owner’s guide called for, or what’s written on the engine.
I have used the baster method several times. Drive a little after doing it, then do it again, a few times. I never got air in the system.
Yeah, with the turkey baster method you would need to do a drain and fill multiple times to get it all out. Then you gotta get all the air out, etc. it’s easier taking it to someone who has a lift, etc. Use synthetic fluid, this will protect the pump and the rack long term.
