Exhaust Bolt size question

[gmhowe]

on my 85 I noticed that the exhaust hangs a little to low and scraps on speed bumps. I checked the service manual and there is a clamp that bolts up to the undercarriage, I don't have that and see the holes for the bolts. Does anybody know the size of those bolts so I can replace them ? Thanx in advance
G

 

[John Robinson]

If you have a metric tap and die set you can use the taps to determine the size of the thread and the thread pitch. If you do not have the taps go to your favorite service station and ask them to use their set of taps to get the correct size. They will probable have the correct bolts in stock.

 

[gmhowe]

thanx John, I've been debating whether to get a set or not, maybe be worth it in the long run

 

[Notorious]

I can't speak for your early car but on my '95 the exhaust hardware is all metric. If it's roughly the size of a 5/16" bolt (but not) it's a M8 x 1.25. If it's larger than that it's a M10 x 1.50. These are both common sizes on our cars and on GM cars in general for the last 25 years or so.