Front Leaf Spring bolt size?

[LivewireBlanco]

1971 Dodge Dart Swinger

I'm not at my car but need to pick up some things while I'm out and about. Does anyone know the size of the front bushing bolt for the leaf springs? I believe my car has 7/16" bolts since it was a slant 6 car but my new leaf springs need a 5/8" bolt so I'm going to replace the bolt and enlarge the hole in the front bracket. Thanks in advance!

 

[TrailBeast]

1971 Dodge Dart Swinger

I'm not at my car but need to pick up some things while I'm out and about. Does anyone know the size of the front bushing bolt for the leaf springs? I believe my car has 7/16" bolts since it was a slant 6 car but my new leaf springs need a 5/8" bolt so I'm going to replace the bolt and enlarge the hole in the front bracket. Thanks in advance!

You might want to verify that bolt size as they seem to have mixed some.
My car was always a V8 car, but it had the smaller bolt.

Also keep in mind that if you enlarge the bracket hole and bolt, you will need the bushing with the larger hole.
I'm pretty sure you thought of that already.

 

[j par]

1971 Dodge Dart Swinger

I'm not at my car but need to pick up some things while I'm out and about. Does anyone know the size of the front bushing bolt for the leaf springs? I believe my car has 7/16" bolts since it was a slant 6 car but my new leaf springs need a 5/8" bolt so I'm going to replace the bolt and enlarge the hole in the front bracket. Thanks in advance!

You mean the big bolt that goes through the eye?
If I'm not mistaken it asked to be a certain length and size.
As in I'm not sure if you can just buy one off the shelf? I'll be curious to see...

 

[TrailBeast]

You mean the big bolt that goes through the eye?
If I'm not mistaken it asked to be a certain length and size.
As in I'm not sure if you can just buy one off the shelf? I'll be curious to see...

Oh yea, you can.
I got the grade 8 fine thread type with the nylock nut, but I did have to get a long shouldered bolt and cut it down at the threaded end so it had the smooth shank all the way through with an inch or so of threads left at the end.

 

[gradedcatfood]

I just purchased mine from a local hardware store, Mcfadden Dale hardware. I did the same thing, enlarged the hole to 5/8 (as I had a slant 6 car as well) and upgraded to calvert racing split mono leaf which needed the 5/8 and had a bushing for the 5/8.

You want a 5/8-18 X 4.5. Course thread would work as well. I just did fine thread because thats what the 7/16 bolt was previously. Also, grade 8 is your friend. Those leaf springs have some weight on them!

I bought a 5/8-18 X 5 as I plan on making my own traction bars and will need the extra length on the bolt but i'm 90% sure a 4.5 inch long bolt will work for stock application.

Hope this helps!

 

[zkx14]

I thought the smallest they used was 1/2". My 75 slant Duster had the larger 2" eye with a 9/16 bolt.
I increased them to 5/8 when I replaced the bushings.

 

[gradedcatfood]

It could of been 9/16 instead of 7/16 but I don't remember off the top of my head. Either way it seems like most aftermarket stuff requires the 5/8 hole

 

[LivewireBlanco]

Yes, it was a mistake on my part. The new leaf spring is 5/8" I know that much. So looks like 4.5" and maybe even buy a 5" and cut it down to only have smooth part in the bushing?

 

[gradedcatfood]

Yes, it was a mistake on my part. The new leaf spring is 5/8" I know that much. So looks like 4.5" and maybe even buy a 5" and cut it down to only have smooth part in the bushing?

Ideally I think it would be good to only have smooth part on the bushing. With the 5 inch bolt I bought I think 7/8 or all of the smooth part fit within the bushing without me doing any modifications to it.