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1st Generation 1964 1/2 - 1973 - Questions & general discussions that apply to a specific year => 1970 Mustang => Topic started by: HDAshmore on January 01, 2024, 05:36:29 PM

Title: 1970 Strut rod question
Post by: HDAshmore on January 01, 2024, 05:36:29 PM
Team,

I have two Dearborn cars.  Both 70, one Boss 302, the other 351C Mach1.  Both made after January 1970.
 
I attached a Pic of my strut rod without the cotter pin.  I know that mine are of unknown origin since car was completely stripped and painted gloss black on all suspension before I owned it. My Mach has same nut and essentially looks the same so no pic attahed.

The pic with the cotter pin has me questioning what is correct.  I can't remember origin of this (first) pic but I just noticed cotter pin and now I'm clueless.  Did different factories use different strut rods?  Why a cotter Pin on the end instead of in conjunctiontion with castle nut? 

When it's time to do both my cars I just want to make sure I'm doing what's right.  I'm along ways off from doing but never to early to source correct parts.

As always, thanks!
Dan in kansas
Title: Re: 1970 Strut arm question
Post by: jwc66k on January 01, 2024, 08:16:07 PM
You need to do what I just did. Look in "Ford Car Parts" (aka MPC, 75 ed, available in the library) section 30, Steering, for both Ford base numbers 3A187 and 3468. I found a cotter pin, 72035-S, referenced used for what you got.
Now, I'm going to state that this cotter pin is not referenced in the "70 Mustang Chassis Assembly Manual", but it is shown on the "1969 Mustang Chassis Assembly" drawings (AM0030, pgs 31-33). Why you got both with and without uses I'll leave to the "wizards".
Jim
Title: Re: 1970 Strut rod question
Post by: Bob Gaines on January 01, 2024, 10:03:31 PM
Team,

I have two Dearborn cars.  Both 70, one Boss 302, the other 351C Mach1.  Both made after January 1970.
 
I attached a Pic of my strut rod without the cotter pin.  I know that mine are of unknown origin since car was completely stripped and painted gloss black on all suspension before I owned it. My Mach has same nut and essentially looks the same so no pic attahed.

The pic with the cotter pin has me questioning what is correct.  I can't remember origin of this (first) pic but I just noticed cotter pin and now I'm clueless.  Did different factories use different strut rods?  Why a cotter Pin on the end instead of in conjunctiontion with castle nut? 

When it's time to do both my cars I just want to make sure I'm doing what's right.  I'm along ways off from doing but never to early to source correct parts.

As always, thanks!
Dan in kansas
Dan the the 69 and 70 Shelby (after aprox 4/69) ,69/70 Boss 302 and Boss 429 used a different heavy duty strut rod then the regular Mustang with the cotterpin. The regular 70 Mustang had a similar heavy duty strut rod without the cotter pin. The 69 Boss used a heavy duty strut rod with the cotter pin and the regular Mustang and 70 Boss used the one without. 
Title: Re: 1970 Strut rod question
Post by: AJ on January 02, 2024, 12:09:33 AM
If it helps, here is pic of the strut and nut on my dad?s 70 Boss 302 as it left Dearborn.  Has never been disassembled.
Title: Re: 1970 Strut rod question
Post by: HDAshmore on January 02, 2024, 03:07:26 AM
Team,

Thanks I'm more informed but still uncertain.

Both cars Dearborn 1970.

My Mach 1 351 C built in February should not have castle nut and cotter pin?  Which it currently does not so may be correct?

My March built Boss 302 should have castle nut and cotter pin which it currently does not, so it is NOT correct?

Does it matter what plant any of them are built?

Thanks,
Dan in kansas
Title: Re: 1970 Strut rod question
Post by: boss167961 on January 02, 2024, 03:54:49 AM
If it helps, here is pic of the strut and nut on my dad?s 70 Boss 302 as it left Dearborn.  Has never been disassembled.
I reckon this is the reply that is most interesting. Nothing beats the physical evidence of an untampered with car that has a known history from birth to current.

I note that the assembly manual shows on p33 that there are two strut rods per car for  [I quote] 1970 Mustang & Cougar 8 cyl & 250 CID 6 cyl [end quote] with the part numbers shown as [I quote] 3A100 L.H
3468 R.H.[end quote].

That is, there is no mention in the manual of any different versions of strut rod between B302 and non Boss cars, or indeed between *any* of the engine variants across the Mustang range.

Further, the assembly manual also clearly shows just one nut on the threat end of the strut rod. It is not shown as a castle nut alone or as well as a std nut. Nor is a cotter pin shown.

But what really interests me is why the hell you would fit a cotter pin at the end of the rod when it is so far away from the castle nut that it cannot even engage with the castle nut?thereby negating the whole point of a normal castle nut and cotter pin setup???

Soooooo?.does anybody out there know what car the pic comes from which shows a strut rod with secondary castle nut and cotter pin? What is the car?s history and provenance? Is what is shown in fact a mod made by a previous owner?

Martin
.
Title: Re: 1970 Strut rod question
Post by: HDAshmore on January 02, 2024, 11:55:22 AM
Oops I missed AJs post and pic.  So my 70 Boss 302 is the same as his unmolested.  Okay so I'm feeling better, but wish I never saw a Pic with a cotter pin and castle nut.  Ill leave it as a Leonard Nimoy "Unsolved Mystery" I guess :).
 Martin I agree with your question, what does the cotter pin do if not engaged in castle nut?  Maybe it's just a last minute failsafe if the nut unscrews completely and the pin keeps the strut rod from pulling out? 🤔

Title: Re: 1970 Strut rod question
Post by: Bob Gaines on January 02, 2024, 07:01:32 PM
Here are some comparison pictures of the big suspension Boss strut rod I was talking about . The one on the right with the wide cross section (think squished out) where it bolts to the control arm is the big suspension Boss strut rod. The smaller one on the left is the regular Mustang. Notice both have the cotter pin hole on the end. I am the first to admit I am not well versed on 70 Boss cars. If this strut Rod is 69 Boss only then excuse the confusion. I assumed it was a D0 (70) part just like the BOSS 302 spindle is a D0 (70) part even though it is on a 69 car. That may not be the case. I am hoping one of the Boss authorities that frequent this forum will give a ruling on if the 70 Boss strut rod is the same as the regular 70 Mustang or not and if so what is the difference.
Title: Re: 1970 Strut rod question
Post by: RocketScientist on January 02, 2024, 09:32:18 PM
Hi Bob, out of interest what have you seen on Shelby's, as 69/70's are a rarity where I live.
Brad
Title: Re: 1970 Strut rod question
Post by: Bob Gaines on January 02, 2024, 10:38:27 PM
Hi Bob, out of interest what have you seen on Shelby's, as 69/70's are a rarity where I live.
Brad
Typically after approximately 4/69 is when all of the Shelby cars got the F60X15 tires (except Hertz) they also got the big suspension which consisted of the big bearing spindles (because of the F60X15 ties)that are made to accept the larger diameter 70 style tie rod ends,different heavy duty strut rods and larger diameter 70 style tie rod ends. Bob
Title: Re: 1970 Strut rod question
Post by: Bob Gaines on January 02, 2024, 10:49:46 PM
The 4/69 approximate date is also when Boss 302 started production . They also used the F60X15 and space saver spare.
Title: Re: 1970 Strut rod question
Post by: hopey on January 02, 2024, 11:33:49 PM
Here are some comparison pictures of the big suspension Boss strut rod I was talking about . The one on the right with the wide cross section (think squished out) where it bolts to the control arm is the big suspension Boss strut rod. The smaller one on the left is the regular Mustang. Notice both have the cotter pin hole on the end. I am the first to admit I am not well versed on 70 Boss cars. If this strut Rod is 69 Boss only then excuse the confusion. I assumed it was a D0 (70) part just like the BOSS 302 spindle is a D0 (70) part even though it is on a 69 car. That may not be the case. I am hoping one of the Boss authorities that frequent this forum will give a ruling on if the 70 Boss strut rod is the same as the regular 70 Mustang or not and if so what is the difference.

Bob, it is my understanding that the squished out version was only used in 1969 BOSS. In 1970 all strut rods were the same, including the BOSS302.   What I do not know for sure is whether that included the 1970 BOSS429.

Also a page from the October 1969 revision of the MPC. Shows the replacement for the 69 BOSS302 squished rod is the standard 70 strut rod.
Title: Re: 1970 Strut rod question
Post by: HDAshmore on January 02, 2024, 11:48:24 PM
Bob, AJ, jim and Hopey.

Thanks all for the responses and research.  I will look at all my strut rods to see if I'm good with 70 style.  I learned a lot as usual. 

Bob I owe you the first beer come Columbus. 

Thanks again all
Dan

Title: Re: 1970 Strut rod question
Post by: Bob Gaines on January 02, 2024, 11:54:37 PM
Bob, it is my understanding that only the 1969 BOSS302 got the squished out version. In 1970 all strut rods were the same, including the BOSS302.   What I do not know for sure is whether that included the 1970 BOSS429.

Also a page from the October 1969 revision of the MPC. Shows the replacement for the 69 BOSS302 squished rod is the standard 70 strut rod.
You may be correct but the books have been wrong before. It doesn't surprise me that the 70 Boss strut rod was the same as the 70 Regular Mustang . The 70 regular Mustang used a bigger bearing spindle (spindle not the same as the Boss)and tie rods. Less parts for more applications.  I too am curious about the B9 application. The MPC seems to indicate it was different yet again for a total of 3 different strut rods used in 69 if you go by the MPC . The big suspension equipped 69/70 Shelby's got the same strut rod as the Boss 302. I have dissembled quite a few 69/70 Shelby's over the years that had them ,the B2 spindles and the bigger tie rods. Those odd and rare parts typically got switched out for more common regular Mustang parts not the other way around.   
Title: Re: 1970 Strut rod question
Post by: boss167961 on January 03, 2024, 01:59:30 AM
Confused.

I have two pairs of strut rods. One set I have just removed from the car. Whilst there were many wrong or repro parts on my car, judging by the pitting and ageing of the ones I have removed, I believe they are probably original to the (June 70 Metuchen built) car. That set does have the squished out control arm mount face but no cotter hole.

The set I am in the process of fitting are mint refurbed originals I got from JD at Allclassic. These also have the squashed out control arm mount face and also have no cotter pin hole.

More interestingly, the picture below is a shot from JDs 1970 stock page where it states that these strut rods are for all Mustangs 70-71 including Boss. Again, this would fit with what the 70 assembly manual shows.

And I trust JD implicitly and he is both a qualified Mustang judge and has never let me down in getting the correct Boss specific parts for my car. He knows his Bosses. So I suspect that this means the squished out control arm mount face is a non issue for 70 model Bosses of any type???.

So where does this and all the discussion above leave us on the cotter pin issue? I?m gunna shoot JD an email to see if he is aware of the cotter hole rods.
Martin


(https://i.imgur.com/xxuOFUH.jpg)
Title: Re: 1970 Strut rod question
Post by: Bob Gaines on January 03, 2024, 02:28:34 AM
Confused.

I have two pairs of strut rods. One set I have just removed from the car. Whilst there were many wrong or repro parts on my car, judging by the pitting and ageing of the ones I have removed, I believe they are probably original to the (June 70 Metuchen built) car. That set does have the squished out control arm mount face but no cotter hole.

The set I am in the process of fitting are mint refurbed originals I got from JD at Allclassic. These also have the squashed out control arm mount face and also have no cotter pin hole.

More interestingly, the picture below is a shot from JDs 1970 stock page where it states that these strut rods are for all Mustangs 70-71 including Boss. Again, this would fit with what the 70 assembly manual shows.

And I trust JD implicitly and he is both a qualified Mustang judge and has never let me down in getting the correct Boss specific parts for my car. He knows his Bosses. So I suspect that this means the squished out control arm mount face is a non issue for 70 model Bosses of any type???.

So where does this and all the discussion above leave us on the cotter pin issue? I?m gunna shoot JD an email to see if he is aware of the cotter hole rods.
Martin


(https://i.imgur.com/xxuOFUH.jpg)
The regular 70 Mustang and according to the MPC 70 Boss strut rod has the wider base (squished out) but no cotter pin hole. It reads like you have the typical 70 Mustang strut rod. It is a non issue for 70 Boss because they are all the same but a issue for 69 Boss where both the wider base and the cotter pin hole are factory. I have known JD for several decades and he has knowledge about Mustangs but I am not aware of JD judging Mustangs in any National Mustang/Shelby venue.
Title: Re: 1970 Strut rod question
Post by: hopey on January 03, 2024, 09:31:18 AM
You may be correct but the books have been wrong before. It doesn't surprise me that the 70 Boss strut rod was the same as the 70 Regular Mustang . The 70 regular Mustang used a bigger bearing spindle (spindle not the same as the Boss)and tie rods. Less parts for more applications.  I too am curious about the B9 application. The MPC seems to indicate it was different yet again for a total of 3 different strut rods used in 69 if you go by the MPC . The big suspension equipped 69/70 Shelby's got the same strut rod as the Boss 302. I have dissembled quite a few 69/70 Shelby's over the years that had them ,the B2 spindles and the bigger tie rods. Those odd and rare parts typically got switched out for more common regular Mustang parts not the other way around.

Marcus has beat us all to it with his research . Page 36/37

https://anghelrestorations.com/wp-content/uploads/2023/12/65-to-73-Suspension-Guide-v3.4_opt.pdf
Title: Re: 1970 Strut rod question
Post by: Bob Gaines on January 03, 2024, 10:58:59 AM
I think the work that Marcus did on his article was well researched and totally satisfies me at least on the subject. Marcus article indicates that the Ford MPC is wrong in that it reads that the 69 Boss 302 uses the C9ZZ-3468-C+D when in fact it the 69 "Boss cars" (I take that as Boss 429 too) used C9ZZ-3468-A+B. Another example of the MPC not being always absolute.
Title: Re: 1970 Strut rod question
Post by: hopey on January 03, 2024, 01:26:07 PM
I think the work that Marcus did on his article was well researched and totally satisfies me at least on the subject. Marcus article indicates that the Ford MPC is wrong in that it reads that the 69 Boss 302 uses the C9ZZ-3468-C+D when in fact it the 69 "Boss cars" (I take that as Boss 429 too) used C9ZZ-3468-A+B. Another example of the MPC not being always absolute.

It is not wrong it just lists the over the counter replacement part not the factory installed part. By Oct 1969 the replacement part for the 69 B302 was the newer part revision. Interestingly it still calls out the A&B revision for the 69 B429 and does not list the 70B429. I guess all that extra weight over the F60-15 needed the squish??.? Or KK was still evaluating the newer part?

EDIT. I checked with David Davis and he tells me that the 70 B429 basically used the 70 strut rod design with the reinforcement but it also had the castle nut and cotter pin.
Title: Re: 1970 Strut rod question
Post by: Bob Gaines on January 03, 2024, 01:39:12 PM
It is not wrong it just lists the over the counter replacement part not the factory installed part. By Oct 1969 the replacement part for the 69 B302 was the newer part revision. Interestingly it still calls out the A&B revision for the 69 B429 and does not list the 70B429. I guess all that extra weight over the F60-15 needed the squish??.? Or KK was still evaluating the newer part?

EDIT. I have been reliably informed that the 70 B429 basically used the 70 strut rod design with the reinforcement but it also had the castle nut and cotter pin. Not sure what the part number is.
What you are describing is the 69 Boss strut rod.
Title: Re: 1970 Strut rod question
Post by: hopey on January 03, 2024, 01:51:13 PM
Bob, I cannot comment or add anything further I asked David if it was the 69 version and he said it no was basically the 70 version modified as described. I would have to defer to him, Marcus, Ed Mayer or other B429 suspension expert. My focus is the 69/70 regular production but I am trying to educate myself on the specials- Eg 69 Shelby and 69/70 KK builds.
Title: Re: 1970 Strut rod question
Post by: HDAshmore on January 03, 2024, 03:05:45 PM
The Marcus article was a huge help and very informative.

I should of looked in the library from the start.

Thanks all.

Dan
Title: Re: 1970 Strut rod question
Post by: jwc66k on January 03, 2024, 05:48:21 PM
I think the work that Marcus did on his article was well researched and totally satisfies me at least on the subject. Marcus article indicates that the Ford MPC is wrong in that it reads that the 69 Boss 302 uses the C9ZZ-3468-C+D when in fact it the 69 "Boss cars" (I take that as Boss 429 too) used C9ZZ-3468-A+B. Another example of the MPC not being always absolute.
Remember that the "MPC" is for replacement parts at dealerships and not "always" what was assembly line installed.
Jim
Title: Re: 1970 Strut rod question
Post by: Bob Gaines on January 03, 2024, 06:29:47 PM
Remember that the "MPC" is for replacement parts at dealerships and not "always" what was assembly line installed.
Jim
Remember also that the MPC does not let you know which part has been superseded or not and which is not like assemblyline. Practical knowledge and observation of original examples goes hand in hand with using the MPC to maximize results. Bob
Title: Re: 1970 Strut rod question
Post by: 69bossnut on January 03, 2024, 08:43:39 PM
Guys to make it simple, 69 had a big suspension and a little suspension. The big suspension use the extra area reinforced strut rod with a castellated nut & cotter pin at the end. This would be 69 boss 302, boss 429 & some Shelby?s after something like around April would?ve got the heavy duty big suspension in 70 all mustangs went to that reinforced style strut rod but it did not have the casted nut with a Cotter pin.
Title: Re: 1970 Strut rod question
Post by: hopey on January 03, 2024, 11:12:59 PM
Thanks David!