Nut size on front suspension?

[Ttumachy]

First - thanks for the help from my previous question on tie rod ends. Have that resolved and moving forward with new brake lines. Next issue is a nut I can not locate from the previous workers tear down. Local stores don’t seem to go this large. To prevent a bunch of back and forth ordering, can anyone point me in the right direction? Any place that sells just a couple extra nuts for the control arm? This is the matings nut for the bolts holding the control arm support. I don’t actually know what size and thread type it is either. 

 

I circled the nut I’m missing in picture. 1951 Plymouth Cranbrook.

Edited November 8, 2020 by Ttumachy

[squirebill]

My parts book for a '49 Plymouth calls out a 13/16-11 nut.  My Machinery's Handbook does not show this thread size in any of the standard lists....I can find a 13/16-12 and a 13/16-20 but no 13/16-11.  The part number in the '49 parts book is 1136 488.

[RobertKB]

Put an ad in classified. This probably is a specialty nut and I’m sure there are at least a few forum members who have a spare one. 

[desoto1939]

1 hour ago, squirebill said:

My parts book for a '49 Plymouth calls out a 13/16-11 nut.  My Machinery's Handbook does not show this thread size in any of the standard lists....I can find a 13/16-12 and a 13/16-20 but no 13/16-11.  The part number in the '49 parts book is 1136 488.

I looked in my Moog Catalog and with th enumber you provided the moog kit  is a moog part number 1050 and it is in the moog kit  k94 and k752  I found the kit k94 on ebay  so look up moog k94

 

Rich Hartung

desoto1939@aol.com

[squirebill]

A Bernbaum also lists the kit. 

[Ttumachy]

Thanks everyone, I very much appreciate the fast responses! So looking forward to having this back in the road for a bit of cruising. Here’s a pic of it in the garage. All original - down to the shocks and springs before I started in on it.

[Andydodge]

The thread used on the suspension pins or bolts is a coarse thread that will allow crease to move along the length of the thread and inside the bushing...........my understanding is that it is not a standard UNF or UNC style thread which are threads designed to be used in the assembly of parts, machinery etc........this coarse thread does allow parts to be assembled and tightened but as the threads are squared off when it is screwed into a bushing there is sufficent space to allow grease to travel the length of the pin/bolt and bush along the gap between the threads.............the nuts are supposedly specially made to be used on these threads.................andyd 

[squirebill]

Andyd....thank you for the clarification on this 13/16-11 thread.  I have never had the front suspension apart on my '49 or '50 Plymouths or the B1B Dodge.  Had no idea of the flat thread of the "Pin" as they call it in the Service and Parts manuals.  At first I thought the Mopar engineers were off their rockers or there  was a misprint in the Parts manual.  After your explanation and seeing the picture of the part on the Ebay listing Rich found above, it is staring to make sense to me.  Pretty clever design.  Can you tell me though, is the bushing this pin goes through also threaded or a smooth bore?  The exploded view in the manual seems to show it threaded.  Please advise.  Best regards to all.

[Andydodge]

Squire.........no worries........the bushes I have seen all have the same internal thread, they have the thread cut with a triangular shaped thread that when the pin is screwed into them results in a small gap that allows the grease to run along the threads........at least thats what I've taken the design to be.................andyd