Pinion seal for 7.5", 8.8", & 9.75" Ford, & also 1985-'86 9" Ford. Pinion seal for 7.5", 8.8", and 9.75" Ford, and also 1985-'86 9" Ford. Yukon Mighty seal.. Yukon Mighty Seals use the latest design and manufacturing technologies to produce a precision fit that seals tight and lasts for years to come.