ball joints 11mm vs 14mm Ball Joints

[Careless]

I have a set of NOS 14mm ball joints that will not fit the 01/70 restoration due to the 11mm taper receivers on the lower control arm steering knuckles.

 

What do I do?

1) have the OE steering knuckles tapered to accept the 14mm ball joints and pretend it never happened

2) purchase 14mm steering knuckles (are there noticeable differences?) and pretend it never happened

3) find NOS ball joints with an 11mm taper

4) buy AC DELCO 11mm taper ball joints (are there noticeable differences in appearance)

 

originality is of most importance, but if the 11mm taper is a safety issue (as it seems, due to the change in size), I would like to know what the best solution is as far as a resto goes.

 

my spidey sense tells me that any NOS 11mm taper ball joint I come across is going to be rusty, sloppy, or not worth the cost.

[djwarner]

The changeover was documented in TS70-60 dated Dec 16,1970 and applied to VIN HLS30-07985 and later. According to the TSB, converting to the later design is possible but requires changing the knuckle arms as well PNs 40052-A8600 and 40053-A8600.

 

The nut sizes were increased to M14 from M12 as the reason for the change. Torque settings 40-55 FTLB.

[zKars]

2) Get a set of 14mm steering knuckles and use your 14mm ball joints. I promise not to tell anyone....

Edited April 20, 2015 by zKars

[Careless]

, oh youuuu, zKars.

djwarner, do you have a copy of the technical service bulletin or know off hand what the reason was? I'll take your word for it and will do a price check on the part nubers, but I am curious to know if it was a safety issue. Mainly because I can ether get the ACDELCO ball joint and consider it "original fitment" as far as replacement parts go. Heck, I could probably even pop off the "MADE IN JAPAN" cap on the bottom of the 14mm one and epoxy it back to the 11mm AC DELCO unit to give it that OEM look and fitment. The 14mm OE ones do not have any other markings aside from that, and the numbers on the rubber boot.

 

but if it's a safety concern, I do not want to put the owner in jeopardy, I will buy the steering knuckles instead (which are probably twice the price of the ACDELCO ball joints)... and just add it to the list of "not stock" stuff that I've been adding to in the event he wants to change it in the future.

 

I appreciate your recommendations and help.

[djwarner]

The TSB simply notates a production change to increase strength. Back then, words like "safety" were avoided in corporate documents. To do so could be likened to shooting themselves in the foot regarding legal liability.

 

The change was fairly early in the first year of production and most likely a design deficiency corrected after feedback from the field.

 

As for originality, I'd be screaming bloody murder if any judge took points away for a safety issue - especially since the TSB says it could be applied to earlier production. Who is to say that the upgrade occurs during the restore or 40+ years ago.

 

I don't have a copy of the particular TSB, but if you send me your email address in a PM, I'll send you a PDF file with all the TSBs for Datsun from 1/69 thru 12/72. Don't remember exactly where I got it from or I would refer you there.

[Careless]

Well noted, and good point on the TSB/restoration thing. I got a fellow Canuck sending a set of those "stronger" steering knuckles to go with my "stronger" ball joints that I have here. Sending you my email now!