Frozen Front End

[Alex Wendorf]

Hi, I live in Az. so what's up? Yikes, I bought a 58 Cab. recently and it came with no up and down motion on front end. I disassembled one side to inspect link pins and shim adjustment, all good. I did notice the upper arm seemed not to square with lower arm. How would I check for a bent arm, either the top or lower, without a special factory jig? Thanks, Alex Wendorf #4350

[Geoff Fleming]

Were you at the West Coast Holiday last year, in Sedona...it was wonderful!
The frozen front end is most likely result of a lack of lubrication. The most common suspects are the link pins and the four bearings which are found inside the two torsion bar tubes. You do mention that the link pins seem in order, so greasing them should be all that is needed.
If you remove the shock absorbers, ( these could be frozen...or even just one),you should be able to get very noticeable up and down movement when the nose of the car is pressed and released. If it is solid, start by removing the link pins, then check if there is movement at each suspension arm.
The suspension arms have needle bearings just inside the torsion tube and these are meant to be greased. Often these bearings are neglected and sieze, which will freeze the suspension. Remove the arms and replace these bearings if needed. Liberally grease!
The bearings can be bought from any good supply house and are not a special Porsche part. A few years ago they were selling in the $15.00 per unit range.
When everything is back together, check the toe-in, as it may have changed a bit.

[Vic Skirmants]

If you pull the arms off the car, use an angle protactor and check to see if the face of the arm is 90 degrees to the tube in both directions. No need for a special tool.

[Al Zim]

Take the shock absorber bolt from the top of each shock. Put your butt on each fender and bounce the car. If it is still solid, take the wheels off and put a jack stand under the bottom link pin on each side. Still solid, remove the pinch bolts on the link pins one at a time and bounce the car. When it finally bounces that is the stuck link pin.
I have never seen a situation where the front torsion bars were frozen with rust etc. I guess that is a Northern phenomina. You are welcome to respong Bruce, Adam and Vic. al zim

[Gerry McCarthy]

Many years ago, when a 356 was a daily,year-round driver, I replaced the frozen link pins on a 2+/- year old C cab, finishing on a Friday afternoon. The owner, a Yale student, left for a ski weekend in Vermont, right from my shop. On monday morning, she was back, absoluty wild, because, on the trip home, the car started "bouncing around, riding like a truck".
I pressed on the front fender,and the car WAS absolutly solid! A Yale chemical prof. was standing there, and asked "did you use Moly grease when you put it together"? In the 60's Molibdimum di-sulfide grease was all the rage, and we used it everywhere. The customer was claiming that we did not replace any parts, just "greased it up" and wanted her money back, my testicles in a jar, my first-born son, and other reasonable adjustments.
My professor friend convinced her that the moly di-sulfide, in combination with road salt and water, forms sulphuric acid, and would rust everything solid in a few hours. When we pressed the pins out, the bushings came with them, and were well seized to the pins. All the parts were new, and in service for 3 days!
If you look in your maintainance book, you will find that only the link pins call for lube every 1500 mi., the rest of the front end, 3000mi. I have never sen frozen trailing arm bearings, even when the needles were rusty, the still moved, but I have seen many frozen link pins, just not in 3 days! We stopped using Moly lubricants in any exposed application.
BTW, Porsche recomendation, for trans with 6:31 pinion and ring gear was Castrol R40 with 30CC of dry Moly powder. It DID give longer life than the then-available gear oils.
KTF

[Geoff Fleming]

Gerry:
I remember you telling us this story at a clinic held in your shop...amazing! Good thing the professor was standing there and he was a chemist not an historian or worse, law professor!
Unfortunately I did suffer a frozen front end , ( 1987),which turned out to be the roller bearings in the upper torsion bar tube siezing. When I removed the suspension arm, one well-rusted bearing race fell out and you could see just how bad it was. The other side was not much better. This was when I discovered that these bearings were available at a local bearing supply house and very low priced, despite being SKF brand.
Things are pretty different up here in snow country where plenty of salt is used on the roads. Those who live in the warmer climes may not realize how lucky they are not to have to drive in those conditions.

[David Green]

A search for help with a sticking driver-side front lower torsion bar turned up this old thread so I thought I'd revive it. I'm just finishing a 16 month recommissioning of my '53 coupe that was in storage in the CA desert for decades. My first test drives revealed a frozen driver-side front suspension so I first checked the link pins which are in good shape and free. Then I removed the stub axel and using a floor jack found the lower torsion bar stuck. Although fresh grease would flow out the end, I removed the zerk fitting, blew out as much grease as possible, squirted in Kroll Oil and this morning was able to "pop" it free with the jack. I flushed the Kroll out with new free flowing grease and worked it up and down dozens of times with the jack. Although better, it still sticks about 25% of the time when initiating upward travel from the resting position and then moves smoothly upward and always all the way down.
Any ideas on how to get the start of its upward travel to be consistently smooth short of removing the torsion bar to inspect inside. My shop manual shows internal bushings and no bearings.
Thanks,
David

[Ron LaDow]

David,
I assume you mean the "lower trailing arm" rather than the "lower torsion bar".
I'd suggest loosening the nut on the front of the arm, removing the grub-screw and sliding the trailing arm out for a good look. Your car has bushings and they might just take a bit of cleaning and re-lubing to make it all as good as it will get.

[Geoff Fleming]

Another easily forgotten culprit that can cause stiffness in the up/down motion, is the sway bar. Over decades, the bar bushings deteriorate and limit its movement. Remove the sway bar, clean from end to end and then grease the outer ends and the points at the supports with the rubber bushings. Graphite powder is very effective here.

[Vic Skirmants]

I would think deteriorated sway bar bushings would increase movement; slop.

[Phil Planck]

No sway bar on a stock 53. Do as Ron suggested. Check control arm surface where it rides in the inner bushing. Check torsion tube for damage(bent).

[Al Zim]

You cannot avoid removing the trailing arm in question. If there are any grooves in the inner end of the trailing arm that are parallel to the trailing arm then the arm is bent. Make sure you have someone check the replacement arm for straightness this requires the factory tool and a set of metric feeler gauges. The measurements are from left to right horizontally and vertically. The tolerance is tight! Be sure you check your shop manual. al zim

[David Green]

Thanks for the helpful replies.

I removed the trailing arm and had to use a locking-jaw puller. I'm not sure if the internal bushings were holding it or it was tight where the torsion bar end fits into the trailing arm (I suspect the later), but once it started moving it came out smoothly. The inside of the tube was full of my recent fresh grease and no other crud. I used a long probe and didn't feel any imperfections in either the inner bushing surface or the outer plastic one. I cleaned and then polished the trailing arm bushing surfaces with crocus cloth and solvent, reinstalled the arm and took it on a short test drive without the shock to get as much motion as possible. It's noticeably improved, now drivable but rather than being frozen solid it sticks and pop-releases occasionally. Also, before assembling the stub axel I moved each trailing arm and the lower is much stiffer than the upper. Is this related to my problem?

As always, advice appreciated.
David

[Vic Skirmants]

Looks like the tube might be bent rearward.

[Phil Planck]

FR%20Tor%20Bar.jpg (38.21 KiB) Viewed 2893 times

Is it possible to get the torsion bar so far out of alignment as to put a bind on the trailing arm? Better than a rearward axle tube.