Lower ball joint nut

[Jim C.]

Trying to replace the lower ball joint castle nuts on my 63 . If I torque them to anywhere in shop manual range of 65-90 ft/lbs I connot get access to the cotter pin hole . If I back the nut off and gain access to the cotter pin hole it is very loose.
What am I missing ?

[Alan D.]

Re: Lower ball joint nut

Let's first see if you have a correct ball joint and nut should look similar to this; And I agree with you something is funny.

[Jim C.]

Re: Lower ball joint nut

Yep that's it. Perhaps the after market nut I purchased from one of our normal catalog sources is dimensionally incorrect ? Probably only need another 20 degrees of rotation on the nut.
Thanks for going to the trouble of taking the pic.

[Joe L.]

Re: Lower ball joint nut

Yep that's it. Perhaps the after market nut I purchased from one of our normal catalog sources is dimensionally incorrect ? Probably only need another 20 degrees of rotation on the nut.
Thanks for going to the trouble of taking the pic.

Jim------


I recommend obtaining slotted nut GM #3983037.

[Larry M.]

Re: Lower ball joint nut

Yep that's it. Perhaps the after market nut I purchased from one of our normal catalog sources is dimensionally incorrect ? Probably only need another 20 degrees of rotation on the nut.
Thanks for going to the trouble of taking the pic.

Jim:

If Joe's part number and suggestion don't work (highly unlikely, as Joe is almost always right) then take a file and coarse sandpaper and trim/cut down the base of the nut by a few thousands of an inch. This will allow the nut to rotate farther and should assist in the cotter pin line-up.

This is trial and error for most folks, but you can actually calculate the amount of metal to remove if you are good in math.

Larry

[Jim C.]

Re: Lower ball joint nut

Thank you. I ordered them

[Joe L.]

Re: Lower ball joint nut

Thank you. I ordered them

Jim-------


One other thing to keep in mind: the original slotted nut used for your application was of GM 280M material grade (SAE grade 5). The GM #3983037 is of GM 301M material grade (SAE grade 8). Many aftermarket slotted nuts currently available are UNGRADED STEEL. Any of those that are found to be zinc plated are HIGHLY SUSPECT. I would NEVER use any of these on safety-critical chassis applications.

Most slotted nuts used by GM were of material grade GM 280M or greater and were of natural or phosphate finish. Very few were zinc plated and those that were were also of GM 280-M or greater material grade.

[Jim C.]

Re: Lower ball joint nut

Joe , Knowing that I'd like to use all GM nuts . Where can I find a parts number listing ? Thank you

[Joe L.]

Re: Lower ball joint nut

Joe , Knowing that I'd like to use all GM nuts . Where can I find a parts number listing ? Thank you

Jim-----

Other than what's shown in the AIM, there really is no listing for all the fasteners used on a Corvette. Even a GM dealer parts man wouldn't be able to help you (or, wouldn't be inclined to help even if they had the information). Most of the fasteners shown in the AIM were either never available in SERVICE or, if they ever were, discontinued by now, mostly without supercession. The advent of the use of the metric system for most automotive fasteners which began more than 30 years ago has resulted in the discontinuation of most inch-size fasteners from the GMSPO inventory.

One of the things that's always amazed me is that GM Factory Service Manuals explicitly caution about making sure the right fastener is used for every application. However, GM makes it difficult or impossible to identify or obtain most of those fasteners.

In any event, I can help you with SLOTTED NUTS. For the most part, the nuts I list are NOT the original part number for your application. However, they are supercessive to the original part number, are usually of a higher material grade, and are configured and finished virtually the same as originals.

upper ball joint-----GM #14032551

lower ball joint------GM #3983037

tie rod end-----------GM #9440271

steering ram to relay rod-----GM #14032551

idler arm to relay rod---GM #14032551

control valve ball stud----GM #14032551

steering ram to frame bracket-----GM #3829413 (discontinued without supercession)

differential snubber bracket-----GM #3774712 (discontinued without supercession)

shock mount shaft to strut rod------GM #14054921

trailing arm forward------GM #3774712 (discontinued without supercession)

spring end bolt------GM #3983037

One more caution with the ball joint nuts: if you are using GM ball joints, the above-referenced nuts should work perfectly. However, if you are using any other ball joints (including "reproductions"), you might end up with the same problem you have even with the GM nuts. That's because the other ball joints might not be manufactured to the exact same specifications as the GM ball joints.

One more thing: in general, when you have a situation in which you torque a bolt/nut to the specified torque and the slotted nut slots do not align with the hole in the bolt/stud, then you apply the additional torque necessary to align the slot and the hole.

[Jim C.]

Re: Lower ball joint nut

Thanks to all for the generous guidance . I'll post my results when the GM castle nuts arrive.

[Edward B.]

Re: Lower ball joint nut

take a file and coarse sandpaper and trim/cut down the base of the nut by a few thousands of an inch. This will allow the nut to rotate farther and should assist in the cotter pin line-up.

Easiest solution - it won't take much to make it fit.