What Size Hex Head For Bench Seat?

Hi everyone,

I'm cleaning up my bench seat and need to take the backs off the base.

There seems to be a hex bolt that is holding in place, while the other side of the seat back is held in place with a kind of pivot that is covers with a flap of vinyl.

Does anyone know the size of the hex wrench as I didn't have one that was large enough....



Thanks!

Quarterwave wrote

Does anyone know the size of the hex wrench as I didn't have one that was large enough....

I just checked mine, and I couldn't quite get an 8mm in there, but 5/16 fit nice and snug.

My 1984 seems to have a random mix of standard and metric bolts and screws. Add (or remove) a little bit of the size due to the rust, and you sometimes have to test fit a couple wrenches t find one that fits.

Thanks Rembrandt - same here, mix of metric and imperial.

Appreciate your help!

Rembrant wrote

My 1984 seems to have a random mix of standard and metric bolts...

It's not really random.   Parts that were DESIGNED (not necessarily BUILT) back before Ford switched to the metric system are inch-sized.  Parts that were REVISED or designed after the switch are metric.  So even if the chair was designed in inches; if the pivot mechanism was revised later, it would have metric fasteners.  That has resulted in a few hybrid fasteners over the years (metric heads on inch bolts, or stud-headed bolts with inch threads & head, but a metric stud sticking out the top).

If you keep that in mind when looking at parts & their PNs (which indicate the design year), you'll grab the right set of tools more often.

Steve83 wrote

It's not really random.   Parts that were DESIGNED (not necessarily BUILT) back before Ford switched to the metric system are inch-sized.  Parts that were REVISED or designed after the switch are metric.  

Maybe Random was the wrong choice of words...lol. What I meant was, I have been mostly working on Japanese and/or German stuff for quite a few years, and I always knew what sockets or wrenches to grab...I could even eyeball the hex heads or the threads and know exactly what size the bolt was. This truck causes me to make many extra trips to the tool box to get the right tools. Sometimes the bolts are standard, sometimes metric, and the metric ones often have uncommon sized hex heads. It's just kind of funny, that's all.

European cars generally use 8mm, 10mm, 13mm, 15mm, 17mm, & 19mm; Asian cars generally use 8mm, 10mm, 12mm, 14mm, 17mm, & 19mm; Ford (after the 80s) generally uses 5.5mm (7/32"), 7mm, 8mm (5/16"), 10mm, 11mm (7/16"), 13mm, 15mm, & 18mm (~3/4").

Land Rover (having been owned by Honda, BMW, Ford, & now Tata) uses every size.

I'm not very familiar with GM & Dodge (Fiat).

Steve83 wrote

European cars generally use 8mm, 10mm, 13mm, 15mm, 17mm, & 19mm; Asian cars generally use 8mm, 10mm, 12mm, 14mm, 17mm, & 19mm; Ford (after the 80s) generally uses 5.5mm (7/32"), 7mm, 8mm (5/16"), 10mm, 11mm (7/16"), 13mm, 15mm, & 18mm (~3/4").

Yeah, the 18mm and 11mm were "new" for me...those sockets had been sitting dormant in my toolbox for a long time. I just started taking the bed bolts out of my '84 last weekend, and the nuts on the underside were 18mm hex (Bolt M12). I think, as a rule, most of my truck has metric fasteners, with the exception of the 302 engine of course. Everything in the bed is metric...M8 hex heads for the head board, M8 carriage bolts in the floor, M12 to frame, and little M6 in the tailgate hinges. I think some of the sheet metal screws have had standard hex heads, but anything with machine threads has been metric. I am assuming that old 3-on-the-tree transmission that was in it also had standard fasteners, but it has been replaced with an M5OD which is metric.