lshlsh2

I need to know the size and grade of the 2 bolts at the bottom of the fender that hold it to the car. Mine are to badly rusted to figure out.
Car is a 71 cutlass.
Thanks Larry

TripDeuces

They are not grade 8 and might not even be grade 5. Are you talking about the two near the door on the rocker panel?

Schne442

Going from memory if you look in the AMK online catalog pg.111 I think part # B-11964 is the correct size bolt. head marking is different though.
Gary

lshlsh2

Yes at the bottom of the fender where they all rust.
Larry

oldcutlass

Grade 2, but a grade 5 is generally what you would find in a hardware or parts store.

MDchanic

Cheapest grade you can get is fine from a structural standpoint.

I hear there's a guy selling a pair of original GM ones on eBay for $99, from a restoration standpoint .

- Eric

oldcutlass

Lol

Run to Rund

GM generally used grade 5 on such stuff, but markings may vary. Suspension, body mounts, engine mounts, other critical stuff used grade 8. If you can get either with the correct washer head, etc. always go for grade 8 unless you are doing a rigorous restoration.

lshlsh2

I hear there's a guy selling a pair of original GM ones on eBay for $99, from a restoration standpoint .

- Eric[/quote]

No thanks just a basic driver.
Probably just use grade 5 maybe 8's. It will depend on what they have in stock. Sometimes the good stuff is in short supply.

I have half a mind to replace it all with grade 5 stainless(unless grade 8 is needed) so I don't have to worry about it in 20 years.
Larry

MDchanic

Mmmmmmmmm... STAINLESS.....

- Eric

-- (just not the real structural ones - it's usually not hard enough) --

Bluevista

Those '99 dollar ones are for a Corvette fuel pump aren't they?

Using grade 8 for sheet metal fastening is like killing flies with a sledge hammer.
Whatever it's fastened into to is going to fail before the fastener even with grade 5.
Body bolts and screws are grade 5 or 5.1 normally, the fender screws at AMK are grade 5.1.
Use the correct Sems type screws with the captured conical washer or they don't apply the pressure correctly on the shims.


They're machine screws and not bolts, generally a screw is torqued from the head and whatever it's threading into is fixed or it taps into the material, a bolt has a nut it can be torqued with.
There are accepted exceptions to the rule like head bolts and a bunch of others because the name stuck before they defined them, it's not an exact science yet.

Lady72nRob71

Tractor supply is great for bolts if you have a store around you.
They sell them by the pound - very cheap!

But not as much fun...

MDchanic

I did not know that. Thank you.

- Eric

lshlsh2

[quote=Lady72nRob71;258570]Tractor supply is great for bolts if you have a store around you.
They sell them by the pound - very cheap!

It is about an hour away but one is going to be built in my town hopfully very soon. It is a great store.
Larry

lshlsh2

Thanks for this info, I knew they were not true "bolts" but didn't know there true names. But bolts sound better than whatmacallits, dohickies or thingamabobs.
Larry

Lady72nRob71

Glad to pass the good word around.
They sell grade 8 and below in most common sizes. This is when it is very economical to stock yer coffee cans in the garage.

I hated the concept of 5 cents per low-grade 1/4" lockwasher at the local big box HW stores!!