Correct ZF-5. This one has the bellhousing bolt pattern to bolt up to a 302/351 and is going into our '88 Bronco.
California Central Coast and Vegas perspectives are clearly different. We were joking about the weak Toyo Kogyo transmission that came behind a 302 being replaced by the far superior ZF-5. What were you thinking of Optimus?
Glad you're gearing up for this swap—it’s going to be a night-and-day difference! If you haven’t already mapped out the whole process, here are a few things to keep an eye on when cramming that ZF-5 into the '88:
The ZF-5 has a different overall length than the Toyo Kogyo. You’ll almost certainly need to have a driveline shop shorten your rear driveshaft and lengthen the front one.
That transmission is a tall, bulky beast. You might need to do some trimming on the floor pan or source a high-hump transmission tunnel cover from an F-250/F-350 to get it to fit without rubbing.
Be prepared to relocate or redrill the transmission crossmember. The mounting points usually don't line up perfectly with the old light-duty setup.
The small-block ZF-5 uses an internal concentric slave cylinder. Make sure to bleed it thoroughly before bolting everything up completely, and double-check that your stock clutch master cylinder moves enough fluid to keep it happy.
Remember that first gear in the ZF-5 is incredibly low. It's an absolute game-changer for crawling out in the dirt, but for regular street driving, you'll be treating second gear as your new first gear!
Let me know how the wrenching goes! Are you putting in a fresh clutch and flywheel while it's all torn apart?
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