Leaderboard

We finally removed and split-open the HF35 in our 2013 C-Max Energi after 222,500 miles. The "grinding" noise had started ~6 months prior (~12,000 miles prior). This is the first serious problem we have had with this car since new. NOTE: I had changed the transmission fluid twice (first time @ 99,659 miles, the second time @ 200,657 miles). The interval recommended by Ford in the owners manual is every 150,000 miles(!). Three of the four roller bearings in our HF35 had severe spalling. I replaced all four roller bearings as well as the pump filter. In hindsight, I wish I had changed the transmission fluid every 50,000 miles; maybe that would have extended the life, maybe a lot, maybe a small amount. I think 100,000 miles was asking too much out of Mercon LV in the HF35 application, let alone 150,000 miles which Ford recommended. We ordered a 2025 Ford Maverick Hybrid (CVT), and I'll be replacing the transmission fluid every 50,000 miles, religiously. I have about ~$250.00 into repairing the HF35 in our C-Max. Transmission has been reinstalled and car has been test-driven: No more grinding noise. Hoping to get another 100,000 miles out of this car. If you are mechanically-inclined, have a "cherry-picker", transmission jack, and are willing to spend ~$100 on bearing puller tools (if you don't already own them), this can be done with the help of a second mechanically-inclined friend/relative, and not that much $$...