# 64 rear axle



## sim (Sep 28, 2013)

hello

rebuilding a 1964 pontiac gto 10bolt rear axle.
i am not sure what color the axle was when it came from the factory. i've seen some complete black, some complete natural and some partially natural and partially black colored
can anyone help me?

simon


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## Roger that (Feb 6, 2010)

Here are some pictures of an original survivor 64 GTO with 8000 miles. Note: Exhaust has been replaced.


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## sim (Sep 28, 2013)

what i can see on the pictures i would say the axle shaft housings are black and the middle section is natural. am i right?

thanks
simon


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## Roger that (Feb 6, 2010)

Some more pictures. To me it looks like there was black paint on everything and some of the paint came off early or did not stick very well. The last picture shows black paint in certain areas that seemed to survive.


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## Roger that (Feb 6, 2010)

Some more pics showing paint runs on the 3.90 axle.


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## geeteeohguy (Feb 2, 2008)

As Roger knows first hand, the paint on the underside of these cars was originally very hap-hazard and sloppy. Some have more paint than others. Pretty much all of them have thin spots and runs. I even thought that the frames weren't actually painted black, until someone on this forum corrected me. I found the proof when I replaced the rear bumper on my non-restored '65 about 2 years ago.....perfect semi-gloss black paint on the rear frame rails. Virtually all the cars you see restored are grossly over-restored!


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## sim (Sep 28, 2013)

ok, thanks


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## allpawl66 (May 9, 2008)

It is also a 1 year only rear as the pressed in bushings are smaller than the others 6 used on the 4 link set-up from 64 - 72 . I have some new if needed .


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## noahfecks (Jul 28, 2013)

clarification please, so from this thread and others I am getting conflicting info. Some say that the axle was unpainted and any paint is over spray from coating the underside of the car. This thread seems like the axle was intentionally, albeit poorly, painted black. Was there any variation from plant to plant? I would like mine to be correct and I am at the point where doing it correctly would require the same effort as muffing it. The above pictures would indicate that the fully assembled axle was painted as there appears to be paint even on the brake lines.

If it were your RESTORATION would you paint it? before or after the axle is assembled? hastily like the above photos indicate or with care to coat it completely?

Sorry I am able to answer most of my own questions with a good internet search but this one is all over the place on the search results


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## 666bbl (Apr 13, 2014)

While many are indeed over restored it's easy to understand why. 1 person is deciding the quality of fit and finish on every component. Each gets that person's full attention either by direction to the shop/techs doing the work or from their own hand. Who would intentionally slop the finish on in select places? I have to be honest here, I would when the time comes. 10 yrs ago I did some intentional "quicky" work under a 68 GT 350 conv. I had red oxide underneath on the floors and subrails, when it was time to paint I purposely held the gun in a fashion to get uneven color here and there. As a finish, just as it was when new, I hastily sprayed semi-flat black on the rocker panel pinch welds letting just enough get on the red below as well. In all fairness the car was so intact and unmolested it was just short of a privilege to restore it. 

Having worked at a GM gear and axle plant, the black paint was really a short term stop-gap measure. Most of the full housings were stored outdoors and got a healthy amount of surface rust when bare. I never did get to go to the plant where they got painted as I was in the gear manufacturing bldg. So what should you do? 1st, whatever YOU want to see or would direct your workers to do. 2nd, go ahead and paint the whole thing but don't worry about getting it as nice as a fender. That does look fake, overdone. Get a run or 2 where it can be seen if one were to look for it, but perhaps not too evident. If you do go in for high point OEM grade judging they can't knock you for excess quality as long as a run or 2 or 6 are evident, even if you must point it out to the judges. 

I agree with the concept that most exponentially exceed OEM standards, but in a sense they almost have to. Would you spend the full value of a car in restoration, only to have it rust and deteriorate just as soon as they did in their heydays? Balance can be achieved during the process, flat clears go a long way, but priming and blocking of frames and mechanical parts should be tempered with an eye toward REAL. I also feel sad for owners of some of the 30s heavy cars with cut and polished frames. They were robbed of their $$$$ in shop rate to do what was never done. Not even on the mighty Duesenberg. Perspective and restraint goes a long way. Embrace the challenge.


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## geeteeohguy (Feb 2, 2008)

Excellent post, 666bbl. Absolutely spot- on, IMO.


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## noahfecks (Jul 28, 2013)

thanks 666bbl, sometimes you just have to hear what you are thinking from someone else perspective

one of my retainer flanges ended up being a little boogered, anybody know where to find a replacement?


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## 666bbl (Apr 13, 2014)

Which flange? Several OEM repair parts are available from aftermarket/race suppliers like Moser, sometimes even Summit or Jeg's carry such parts.


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## noahfecks (Jul 28, 2013)

lots of aftermarket available but nothing suitable for a restoration. Will probably have to come from someones parts stash


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## propuckstopper (Jan 20, 2012)

*Just Completed Mine...*



sim said:


> hello
> 
> rebuilding a 1964 pontiac gto 10bolt rear axle.
> i am not sure what color the axle was when it came from the factory. i've seen some complete black, some complete natural and some partially natural and partially black colored
> ...


When I was looking to redo the rear axle on my 1965, I spent a fair bit of time researching various finishes and methods. While I cannot confirm that my method is 100% correct, I can tell you that a very prominent GTO restorer uses this process for cars that will be driven. I liked his method, so I decided to follow it to the letter. I am extremely happy with the result, and I don't have to worry about rust like I would have otherwise.

I took what was the very nice original housing out of the car and completely disassembled it. I then very diligently steam cleaned the inside of the tubes and the centre section. The inside of the housing was now spotless. I then spent a great deal of time sealing up (masking) the ends of the axle tubes and the rear cover area. I then had it glass-beaded, and brought it back home. 

I sprayed the entire rear housing with SPI epoxy primer, then gave it a couple of days to dry. The next step was to paint the centre section, which I have always understood to be a cast part. Here, I used a good quality cast grey finish. I then let this dry for a couple days.

Next, I carefully masked off the centre section to protect the new cast grey finish. I then proceeded to paint the axle tubes and the drum backing plates with a "natural steel" paint from Eastwood. This gave the axle tubes a distinctly different appearance than the centre section. At this point, I had my "factory" finish: a cast grey centre section with natural steel tubes and backing plates. This is the way I understand these rear ends to have been installed on the production line in 1965. 

The final step was next. I hung the rear end relatively high up in the spray booth to simulate the car going down the assembly line with the rear end installed as it would have been in 1965. I then took my spray gun (filled with chassis black) and "fogged" the entire back of the rear end, the shock mounts, and part of the backing plates. I also went underneath the rear end just a bit, to simulate walking under the car on the assembly line. 

I did not make "runs". I just put enough black on to simulate a quick production line mentality, which is the way I understood this whole process to be. My goal was not to be the best production line guy, nor the worst. I tried to remember that these guys were not building show cars in 1965, so my goal was to fog this rear end and "get ready for the next one". 

Following about a month of curing, I wrapped the rear end up heavily in bubble wrap and had a very experienced driveline shop install a new ring and pinion, an Eaton Posi, new axles from Dutchman Motorsports in Idaho, and all new bearings and seals. 

As I said before, I could not be happier with the result. It really turned out nice.


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## 666bbl (Apr 13, 2014)

^ ^ ^ ^ ^ ^
That's what fuggin restoration is all about. Keep in mind, some plants were better than others at the job. To keep it looking like the day it arrived on the truck that process above rocks. But still, no picture?


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## propuckstopper (Jan 20, 2012)

*Picture*



666bbl said:


> ^ ^ ^ ^ ^ ^
> That's what fuggin restoration is all about. Keep in mind, some plants were better than others at the job. To keep it looking like the day it arrived on the truck that process above rocks. But still, no picture?


Here you go.


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## geeteeohguy (Feb 2, 2008)

There was a photo awhile back on the other forum of a '66 GTO on the production line with the red painted brake drums that the Rally 1 cars had...anyway, the red drums on the rear had black spatter all over them from the rear end being 'sprayed' semi-gloss black. Pretty sloppy, but it's how many of these cars were built.


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## noahfecks (Jul 28, 2013)

so more questions...

I really liked the ideas that the goalie put up so I am doing my best to recreate this method. You said that you used chassis black on the axle, my restorers guide says 60* gloss black for paint, but the o-so-dangerous internet says satin black (same as chassis). Anyone know for sure which is right?

Also before I do a final install of the steering parts, restorers guide also says all parts are 60* gloss black , are there any parts that should remain natural steel? Anyone able confirm the gloss black color over the satin black?

none of my restoration guides say anything about inspection paint marks, can anyone point me to a source that could tell me right from wrong? My google foo didnt come up with anything. Anybody do judging that might be able to tell me what the expectation is (i can look at the judging guidelines, but is eastwood detail gray ok for natural steel parts)?

thanks again


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## propuckstopper (Jan 20, 2012)

noahfecks said:


> so more questions...
> 
> I really liked the ideas that the goalie put up so I am doing my best to recreate this method. You said that you used chassis black on the axle, my restorers guide says 60* gloss black for paint, but the o-so-dangerous internet says satin black (same as chassis). Anyone know for sure which is right?
> 
> ...


I used Eastwood Chassis Black. It has a nice sheen.


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## advchaser (Jan 9, 2017)

*Axle Code Format*



Roger that said:


> Some more pics showing paint runs on the 3.90 axle.


Great Pictures. Thank you. 

I have not seen anyone describe the axle codes in the format you provided. Even the allegedly factory manuals do not describe the code as you mentioned, so I am perplexed. Do you have a resource? 

My axle code looks to be P2 93 L, which, if I decode it the way you did means I have 2.93 gears and L for limited slip maybe? I say this because I have there is a tag that says: "Use Limited Slip Diff Lube Only." But the car is 53 years old and maybe someone put the tag on for weird reason. 

Thanks for your time.

Cheers,

Bob


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