Crank Pulley Bolt Size?

ReefBlueHatch

Active Member
Jan 12, 2010
682
96
39
Central KY
Anyone know what the size/thread is for the crank pulley bolts? My 5.0 is the only vehicle I have now, so I can't take out a bolt and then drive somewhere. I'm putting on a set of underdrives, so I need to find them in a grade 8 allan head.

Thanks for any help!
 
Actually, i think you'd be fine with 3 bolts in there. I ran with only 2 water pump pulley bolts for YEARS. But, you could always just take a wrench with you to the hardware store, pull off a bolt in the parking lot and go inside and match it up and then put it back on outside.
 
your factory bolts should work w/ underdrive pulleys, what's the need to change them?

With the crank pulley being so much smaller, the bolt holes are closer to the edge so you have to use allen bolts with a smaller head. I'm buying a used set without bolts.
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