finally got around to putting in some KYB gsx shocks / leveling springs and whiteline panhard bar. however seems the passenger corner is 1/2" to 1" lower than all the other corners. i need to really take it out to get things to settle in , but do you think it could be one of the springs needs to be rotated? i installed them EXACTLY the way the stockers came out as far as orientation , but for all i know that could have not been right. i will post pics hen i get a chance. can i disconnect the swaybar and shock and lower the rear on one side to rotate the spring if needed? i really dont want to remove the damned frame connectors again!

would the orientation of the spring make that much of a difference?

 

So one of 4 corners is lower? Only way is car is twisted. I'd find a really flat plane to park it on and check it again, measuring from ground to top of fender arch at center of the arch. I was gonna buy those springs once, but now our '08 GT is 28-1/4" at all four after I shortened the rear springs. Sits on235/55R17 tires. 1 round plus an inch more wire. Did it October 2013. Then I put some rubber isolators on top of the springs, probably added back 1/8" of height. I cut 3/4" off the bump stops too.

 

Oops, did not realize it double posted?

 

Consider using the edit post function over double posting lol.

 

Just now noticed that my double post was even noticed. I edited my extra post and never returned to thread ... nor looked further. lol.

 

All good

 

now im starting to get pissed. i just re adjusted everything to make sure it was done on the even garage floor. tried turning the springs different ways to see if one side would settle lower. i unbolted the panhard bar and retorqued. what could be causing this 1" difference? i read on the cj pony site that somebody had a similar experience. i made sure the chassis braces (i have a vert) were loosened and torqued in the correct sequence. if there is a difference in those would that cause the car to flex by that much? im trying to figure out everything before blaming it on the springs themselves

 

The S197 is about as stiff as a unit body can be, but the convert is less so as it has no roof to stiffen it, so those braces are used. That might be where the issue stems from?
If you are seeing a 1" difference at just one corner, either 1) the floor has a dip or rise in it, 2) your measure method is flawed ... or 3) the car is twisted.
Springs will not cause just one corner to be off unless the car sags in a corner.

Think of two panes of glass, lay one on the other, unless one is curved or twisted, all 4 corners meet. If just one corner is off, then a piece of glass is not flat. Is it the ground or the car or just the measure method?

 

im going to try to loosen / retorque the braces with the car supported by the axle (and ill put a level on it to make sure). yes i see the difference only in the one corner , all the others are 28-1/2. my garage floor is a typical slab , i would be surprised if it has a 1" dip , but stranger things have happened. when i first did the spring job , i had the car backed in half in the garage half out , and the driveway area is more uneven although not horrible. i measured ground to center of fender, and i also measured on a flat parking lot with same effect and plus you can notice just by looking at that one side.. will try the braces this week and report back

 

i dont know why i dont have luck getting cars to go down the road without vibrations and shakes... never fails. so i just had the car aligned , i have the single piece ford racing drive shaft , panhard bar (centered the rear by eye) , roush leveling springs , and just to make sure , i installed a whiteline upper control arm to adjust the pinion angle even though its not a drastic drop. the vibes starts at 75mph and gets more pronounced through 80-84 and it present in some way up through 100 . feels like its through the floor with some noticeable shake through the wheel (although doesnt feel like a shimmy). i just want this thing to be smooth! i have oem struts / springs up front ,

 

Vibrations like you describe

Quote:

the vibes starts at 75mph and gets more pronounced through 80-84 and it present in some way up through 100 . feels like its through the floor with some noticeable shake through the wheel (although doesnt feel like a shimmy).

are usually the result of a bent ... or at least out of balance driveshaft, a very worn tail-shaft bushing in the transmission, or a bad, worn universal joint ... or two.

One or all of those sound to be at play.

Springs will cause sagging, leaning while shocks can cause uncontrolled rebounding of the suspension. I do not know your experiences, abilities ... I think you should get an experienced mechanic to test drive it. I don't know how detailed or accurate you describe it either, may turn out to be just a bad tire.

 

SWAG -- it is the one-piece driveshaft vibrating; and it is doing it because the driveline angles are messed up in these cars; very difficult to get the pinion angle "just right" so it is smooth across all speeds and conditions, probably impossible . . . you might be able to minimize it by playing with the pinion angle

the original driveshaft has the joint in the middle to "mitigate" this issue

I think I might have the same issue you are experiencing, due to my Shaftmasters one-piece driveshaft. At some speeds and load conditions (generally light throttle or coasting) I get a pulsing vibration that goes through cycles; as if the driveshaft is vibrating around then settling down then vibrating around again. I did have the pinion angle set per recommendations; but the issue is that the differential does rotate a bit under different conditions (like heavy throttle versus coasting) and the pinion angle changes a little as that happens, so even if the pinion angle is perfect under one condition, it can be off under different conditions. I think the vibration disappears under heavy load because all the joints are tight and it can't shake around as much.

so anyway, you might play with the pinion angle and see if it helps . . . I have been meaning to do this, but it's a real pain to get in there to adjust it, and it will be trial and error, so it is going to be a time consuming exercise

 

I'm sorry, I forgot to mention driveshaft U-joint angles, but as pointed out, that could be your problem. If you look at a universal joint and two yokes, there is a driving end and a driven end. There are only two conditions where they both turn at the EXACT same speed. One is when stopped dead. The other is when they are in a straight line. Any angle between them, and assuming the drive yoke spins at a constant speed, the driven yoke changes speed 4 times to make the same revolutions, twice speeding up, twice slowing down. Greater angles increase the degree of speedup/slowdown.
Drive shafts are phazed to have each end countering the other end and if not in phaze, you will feel it more at higher speeds. Excessive angle at one end will do it as there is no countering action.
At speed the engine with flywheel or torque converter tends to rotate at a steady rate. The car moving at speed on a roadway maintains a steady speed or rate change due to mass and inertia, same as a flywheel. If the U joints and drivetrain have built in osscilations, you'll feel it.

 

had the car at a driveline shop to check all the angles etc. they didnt see anything out of wack. does anybody know a shop that deals with modded cars in the morris county NJ area that can figure this out ?

 

^ yep, that is the issue with the driveshaft in these cars -- it is very hard to get the equal-and-opposite angle on both ends, so the "phasing" cancels out . . . apparently the additional joint in the middle helps with that somehow, I am not sure exactly how

Assuming they know what they are doing, it could be as good as it is going to get -- the other problem is that the pinion angle changes under different load conditions, because the differential rotates a little, plus things change as the suspension moves up and down. So they do their best to guesstimate how much the differential will rotate and then set the pinion angle at rest with that in mind. You might be able to improve it by playing with the pinion angle; to do that you need an adjustable upper control arm. If you don't have an adjustable upper control arm, then there is no way to set the pinion angle; in that case the shop must have just checked it and said "yup, close enough, nuthiin we can do about it anyway"

 

The only way is to phaze each shaft on it's own.

Trans Yoke --< I--Shaft with Bearing@Yoke--I >--Shaft with Slip Joint--< I--Diff Yoke

It's how 2 or more shafts are phazed between yokes in carrier bearings in long WB trucks, it's to shorten shafts to minimize "jump roping".
A double cardan joint is like a super short drive shaft and it self cancels but at the cost of complexity.

 

Or unavailability of replacement/repair, in the case of the S197s.

Here's the one place I can even find the listing of the driveshaft... or propshaft as they're sometimes called:
https://parts.ford.com/shop/en/us/tr...rive-7817759-1

And notice that not ONE of the joints can be had as a part number. All or nothing. And right now, nothing. :| Shafts themselves are on backorder, and that's about the only way you can replace the center carrier. The CV joints might can be rebuilt. The U-joint might can be swapped out. Heck, I've actually done the research and *have one on my bench*, but didn't use it (no point, the original is still fine.) But that center carrier bearing is the knockout on these things.

So... can't get the things fixed, can't get them new... and even if you could, the replacement is as costly or more than the single piece aluminum Ford Racing one, hence my decision overall to abandon the two piece when my center carrier went out and get the Dana Spicer... er FP 4" aluminum single piece. Car's peppier anyway!

Just... irritating. I mean, I knew why it was two piece, and I was *fine* with it. Just wanted to fix it. But can't. Not that I've found was worth it. It's about as bad as the gigantic exhaust setup on the S550 GTs. I really don't get that at *all*. Ford does some stupid things, I swear...

/Just rantin' a little, ignore me, it's fine.