Need Upper Control Arm Stud Size for C25

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tnellessen

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Tim
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I need some help finding a bolt size, I have been everywhere searching for the answer and haven't come up with much. I believe I have a two part question:

1) I am led to believe that the stud for the upper control arm on a 78 C25 is a different size than a C15, LMC sells the studs for a 1/2 ton, but does not have a part # for a 3/4 ton. Are these in fact different sizes?

2) If they are in fact different sizes, what is the correct size that I need? I will simply replace with a grade 8 bolt if I can't source an actual stud to put in there.

This is the only thread that I could find on this subject, but the OP is looking for a 1/2 ton I believe. I need these same things, but for a C25.
 

idahovette

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20s and 25s are bigger...I'm guessing 9/16 fine thread?? AND they have serations(SP) just at the head, which is flat, to stay put in the frame when adjusting caster/camber. May have a number for them in a book out in my shop... Wil check.......
 

tnellessen

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^^^Thanks for this, I assumed they were different but wanted to verify. I can't find a source for new ones anywhere. Acknowledge the splined shafts to ease alignment jobs. I may just tack them in as Mr. Clean suggested in the linked thread if I can't find a source for new ones.
 

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