HELP 1973 plymouth roadrunner u bolt diameter

[midnightrider1818]

i have been rebuilding the rear end on my 73 rr. i have new u bolts but they look to be too small in diameter because they dont fill the holes up on the brackets. they take a 3/4 inch nut. does this sound right or should the u bolts fill up the holes in my brackets. anybody have any experience with this ???. thanks guys

 

[RustyRatRod]

Are you SURE about the nut size? That would mean the u bolt is 1/2" and that would be the largest diameter u bolt I've ever seen on a passenger car. Can you double check that? I have my friend's 73 340 4 speed Road Runner out in the shop RIGHT NOW doing work on it. I'm gonna look at it too.

 

[midnightrider1818]

Are you SURE about the nut size? That would mean the u bolt is 1/2" and that would be the largest diameter u bolt I've ever seen on a passenger car. Can you double check that? I have my friend's 73 340 4 speed Road Runner out in the shop RIGHT NOW doing work on it. I'm gonna look at it too.

well the socket that fits the nut is a 3/4 inch socket. look and see on your buddies roadrunner if where the u bolts go through the brackets at if it feels up the whole hole or is there a gap between the u bolt and the bracket holes. ill go out there right now and try to measure the u bolt. i dont have a caliper but will try with a tape or something

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actually the nut size is 1/2'' by 20

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and it looks like the diamteter of the u bolts are 3/8'' with a tape measure

 

[RustyRatRod]

Nevermind. I am havin a major brain fart. I was thinkin drive shaft u bolts. Yeah, 3/4 is the right size for axle u bolts. Damn. lol Sorry bout that.

 

[midnightrider1818]

ok so i guess i have the right size then with a 3/8 inch u bolt

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like i said the thread size is 1/2 inch by 20 and the socket that fits the nut is a 3/4 inch socket

 

[RustyRatRod]

Yes sounds like you're fine. Sorry about the kunfrooshun.

 

[YY1]

There should be a little gap, to allow for a not too preceise bend on the U bolt (since a lot are hand made), and so you don't scuff the threads up real bad trying to hammer it through.

 

[ArtH]

These guys were a big help for me. http://www.stengelbros.com/U-boltKits.htm My Cordoba needed 7/6 bolt (A) 3 1/8" spread (B) and 5 1/2 long (C). They made them for $7.49 each and I had them in two days. They dropped in perfectly. The nuts were 7/16.