I recently bought a used 2011 F150 with 120k on it. I changed all fluids (f/r diff, transfer case and radiator flush). Should I change the transmission fluid, I don’t know if it’s been previous been done? If so, change or flush? The truck runs fine. No slips. Thanks
I would just do a drain and refill, and perhaps the filter is there is one. Based on your description, it is probably fine to drain and refill and do a filter. But I would NOT flush it (especially with that many miles -- and some mfrs actually tell people NOT to flush their transmissions).
But just keep in mind with a "high-mileage" vehicles (over 100k) it's a bit of a risk, but if it's shifting smoothly, you're probably fine. Just use the OEM Ford fluid.
How does the trans fluid look now?
