No it wasnt.. there is a difference between the repeatability of tolerencing and custom making something to fit a singular and specific object. Technoligically the measuring equipment was just not available. Now if you really dont believe me I have a couple sets of spring calipers and some hermaphrodite calipers, and some steel faced micrometers thats accuracy changes depending on the weather, that I inherited from my grandpa who was a machinist up untill he retired in the early 80's. If you really want me to prove your point on the accuracy of the tooling you can come down and use those to measure a whole bunch of things and give me readings, then I will throw them up on the CMM and tell you what the actual measurements are... One of the first machines i started out running was a old punch card VTL made back in the 60's converted over to running off of a 486 PC. It was a hydraulic controlled machine and we use to have to put dial indicatiors on the gibbs and ways. As the hydraulics warmed up the true position on the machine would move .020-.050" so we use to have to tighten the gibbs to adjust the tolerence back in...so yeah thats what type of precision they had back in the 60's and 70's.
Glad I read this thread. I had no idea a lot of these cars leaned to the drv's side. I don't knw if my axle is, or how far it might be to one side - that's not really important, cuz don't really plan on any really big tires. My car leans also. I thought it was a sagging spring, cuz the rears looked to be orginal. I replaced all the springs "18 mos. ago" and it still leans abt 1/2-1 1/2". The car was in an accident at some point and the left side was repaired. The left fender & hood seems to be the only place the car's paint is not original. Since I see it's a common issue Im not concerned abt it anymore.
So, I guess you were in charge of setting up Ford's assembly line back then ? That's basically what you're trying to make us believe here.:16suspect I mean, come on, we sent men to the moon back then, but your telling me we didn't have the technology to center an axle ? And lets not forget, we actually built nuclear weapons during WWII, with technology that couldn't center an axle ?
No I am stating the obvious the tolerencing was not that good, I have seen the prints for the Saturn V missile programs so I know exactly the tolerencing that they used to send a man to the moon. I use to work for a little company called ATK..or as most people know it by its previous name Morton Thiokol, and guess what we built? Of course currently I work for Parker Hannifin aerospace and all we build here is flight controll systems.(http://www.parker.com/portal/site/P...&vgnextdiv=687631&productcategory=productline) Just a quick question... how many rocket failures happened in the 60's.. now think about that and think about how accurate they were able to build large scale components back in the 60's Hmmm you think there is a correlation, how many of those failures were due too mechanical failures? Its interesting how you look at the mechanical history and when we were in the stone age of the industrial era we had many many failures, but as we perfected our processes and made everything more accurate our failures become less and less. Now if you want to keep telling me this and that fine but unfortunitely I have been stating facts...You on the other hand remind me of my 2 year old and my 4 year old bickering with each other(almost like you want to argue just to argue..its either that or you think if you throw a big enough tantrum I will conceed and say your right). I use high precision measuring equipment almost every day and I have also used many of the machines they ran back in the 60's and 70's...stupid job shops... Currently I have many different jobs ranging from high precision machining and grinding to HVOF tungsten carbide flame spray, to NDT testing, Mag Particle(commonly known as magnaflux) and penetrant inspection. The quality and the accuracy of the machines is substantially different between the generations. So now you know a little of my background, whats your credentials in the matter?
I've worked with Sterett micrometers since before the 70s and I still have those mikes. They are the most accurate tools for measuring thicknesses that I have owned. One measures to .0001" +/- .00003" and is as accurate today as it was in the late 60's. Holding tollerances on an assembly line has always been necessary and a function of cost. A 40 year old car that sags did not sag when it came off the line - is a function of time and use not factory tollerances.
You don't need extreme tolerance measurements to center an axle. That is my point. All it took was effort + money to do so. But that decision was obviously made higher up the food chain at Ford not to do so, simply because it wasn't deemed a priority, or neccessary to do so. You're taking this thing to the nth degree. And funny you should mention Morton Thiokol and failures. I've actually worked in welding shops and know what it takes to center an axle, without an engineer around to look over my shoulder, telling me I'm not "doing it his way". I KNOW what WORKS. And I've seen many failed engineering designs that don't. So don't sit there and claim to be somehow superior to others just because you have a piece of paper that says you went to college.
DING! DING! DING! Ladyyyy's and gentelmannn,, The judges have scored 60-40 and 40-60,, We have a draw! Are we able to agree that you two have knowledge and experience that does help us understand things in different ways? I do.. What I would like to know is what do we consider doing to correct the two issues of sagging and offset. If the springs are new, where/what mods should be made to correct the lean? Is it actually leaning from the front or rear? Everyone seems to see it leaning at the rear but I always wondered if it isn't actually a result of something going on up front. I also wonder if the axle housing is different in length from left to right side. Anyone ever look into the offset cause close enough to determine the best solution of corrective action?
the offset can be caused by the shackle bushings being worn out. this would let the shackles sit at an angle letting the springs move to the side. if some one really wants to make sure there car is perfect it would need to be put on a frame jig and all the factory tolerances would need to be checked and adjusted. then you would find the slop in the factory tolerances and would need to tighten them up.
That's part of what I was thinking about this. In between the two rubber bushings in the spring eyes, and the four rubber busings in the spring shackles plus the flexing side to side of the what ? Four foot long leaf springs, it's a wonder the axles comes even that close (+ or - 1/2") to being centered. Then add in the age factor of the bushings, that further adds to the problem of centering it. Like I said before, it's really not an issue until you max out the wheel wells with the fattest wheels and tires you can fit there. As for the leaning aspect, I've never noticed mine leaning, but then again, I haven't taken the time to look at it that way.
The best you can do is go with Polyurethane bushings to remove the slop of rubber bushings, but there you make a tradeoff in ride comfort. If you really wanted to get it dead-on perfect, you could fabricate bushings from bronze to replace the stock bushings at all points, then add grease fittings to keep em lubed. That would really tighten up the suspension in the rear, but I'm not sure how it would ride, it would damn sure handle better though. This would be basically how the front suspensions on semis are done. It would be interesting to see how it would work in a light weight vehicle such as these.
I like the idea of the bronze bushing because these (shackle) bushings are not really gonna transfer impact shocks like a more ridgid mounted located bushing such a a radius rod bushing might. Seems like the shackle bushings do more rotating than absorbing vibrations. I'm sure there may be some impact felt so the Poly may be the best choice for a car that is used more as a driver. I plan on weekend full throttle playing so either choice would be ok for me. Since Poly is probobly the ones I can actually find, that is what I will go with.
I am wondering if these cars unibody construction, along w/ aging play a role in the sagging? Im wondering if the sagging is in the middle of the car. I really have not seen enough of them to have realized this was somewhat common. The greatest number of cars I've seen were in Dearborn this past July and I really did'nt look for the sagging. It's not really that obvious. I have not seen any noticable sagging in others unibodies, Camaros, Stangs, Cuda's etc., maybe I have not been lookin hard enough.
Sagging mostly happens when the floors and inner rockers rot out, 99% of the time in convertibles because the absence of a roof
Another factor in the cars leaning is the offset gas tank. Liquids are pretty heavy. It may be a few inches, but over time, it will wear on the car and suspension components. This is an especially bad problem in 1990s Ford Explorers ... the gas tank is fully on the left side, right behind the McDonalds-fed driver. The driver-side leaf wears out a lot faster. In that community, they call it the "gangsta lean". Common cure ... swap rear leaf springs side-to-side and crank some of the height out of the passenger side front torsion bar.
