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Discussion Starter #3
It is an adjustable lower control arm just like it says it is? Not sure I understand your question?

Mike--94MSP9C1
At first I thought it was a lower control arm, but then I wondered if it was a pan hard bar. It says "lateral".
 

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At first I thought it was a lower control arm, but then I wondered if it was a pan hard bar. It says "lateral".
Well they call it a control arm and I did not see anything about it being a Panhard bar in the description?

Mike--94MSP9C1
 

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It almost has to be.
 

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Goofy applications - nearly all FWD, so the adjuster must be for rear alignment. But what possible value for 'performance dialing' the pinion angle on 2 mismatched model Cady barges or a wagon ????

See what you've done Mr. Harrison? Everyone's confused now.
 

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Discussion Starter #8
Is this something that would be desirable to SS guys who are trying to fix the factory axle location issue?
 

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The ISSF-approved way to adjust the rear wheel relative to the body, is to use either longer rear control arms, or adjustable-length rear control arms made longer.
If the extension is greater than 0.5", the driveshaft yokes will also require attention.

What GM used to do officially was adjust the mating of the body to the frame. Anyone who's gonna replace or upgrade their body-to-frame bushings might want to give this a try.
 

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Is this something that would be desirable to SS guys who are trying to fix the factory axle location issue?
Yes, they end up performing the same function as several brands of extended LCAs. However, EVERY set of those installed, whether the 1/2", 5/8" or the 3/4" flavor, requires the corresponding UCAs to retain proper pinion angle. Installing only extended lowers puts more strain on the u-joint - and I guess robs power to the ground.

The ISSF-approved way to adjust the rear wheel relative to the body, is to use either longer rear control arms, or adjustable-length rear control arms made longer.
If the extension is greater than 0.5", the driveshaft yokes will also require attention.

What GM used to do officially was adjust the mating of the body to the frame. Anyone who's gonna replace or upgrade their body-to-frame bushings might want to give this a try.
There's been scads of debate on whether, if or when the driveshaft (or its yokes) needs lengthening to maintain adequate spline coverage on the output shaft. "True" wheelwell centering is a full 3/4" reward of original design. But I think it was Hotchkis did just 1/2" as a nod to getting some visual relief while not requiring anything else replaced. For multiple reasons on mine I chose the METCO 3/4"; comparatively minimal power adders not anywhere near presumed unsafe, much cheaper than alt. suppliers, and genuine full correction of the designed in error.

Interesting story: I later snagged the neato Crown Vic MMC composite driveshaft (which BTW also requires the 3/4" extended control arms) but found it did NOT fit. I learned then that the METCO (at least their 1st gen model) is actually only 5/8" (for some never discovered reason), so hence the painfully entailing process of having almost 3/16" milled off the end of the forward yoke. But there's more. I assumed the rear is at its "furthest" arc rear when fully suspended in the air, and compresses closer to the front upon compression. Nope. I could have just jacked the pumpkin a bit to allow the rear u-joint into the yoke and it would have still been clear of bind when fully relaxed again.

Back to thread related: the most important reason again that this part will NOT work under any B- or D- body is there's nowhere to mount a swaybar. Therefore useless, unless using (I think) the Trailblazer or some later-discoverd FOMOCO type bar mod that mounts firectly to the frame and the axle housing.

Marky, maybe I read wrong, but I never heard of GM doing anything themselves (as a TSB or recall or 'repair') to correct the "off-centered" axle location. Urban legend has it that the (visually garish and assaultive to many) flaw was 'designed in' as a result of using the prior gen boxy frame without correcting for the slightly 'longer' whale gen body. So, when they lost the goofy rear wheelwell from the '88 Cadillac Voyage concept, you can see they woulda' had to redesign and restamp the rear doors a little shorter - or extend the frame. So the choice was clear: = do nothing. Brilliant! No way Jose' gonna go through all that on a known-to-be-doomed platform ina couple years eh.

Cliffs: No. Bar is useless for anything but the wrong wheel drive applications listed.
 

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96 Black,

Prior to joining the ISSF, I lurked, since 2001; mentioned because much of the ISSF's partial recovery of precrash data does not reach back before 2003.
Anyway, over two frakken decades ago, there was a TSB? or something along those lines? stating that if a Caprice owner complained of the rear-wheel off-center issue, that the dealership should
a) inform the customer of the cost of lifting the body off the frame, re-adjusting the body relative to the frame, and then remarrying body to the frame.
b) make clear that the wheel and suspension alignment are separate and independent of any body misalignment - that aesthetics and functionality are not connected here, and that if the customer could tolerate the odd looks, the suspension works fine.
c) after being sure that the customer understands, do as the customer wishes, at their cost.

Anyway, point is, almost none of the ISSF could technically justify a merely aesthetic mod, when what we came up with - longer rear control arms - was both an aesthetic upgrade, as well as a chance to upgrade the c-channel rear control arms (that can be visibly twisted like a rope by anyone with decent grip) to either a solidly boxed or tubular set of four.

Don't know if Autocrosser knew about Dick Miller Racing's Rear Triangulation braces, but they were either unknown, or did not penetrate the ISSF's conscious, as I've NO memory of them being mentioned in the early noughties …
 

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I had not known of such a TSB. 'Body shifting' is of course feasible, plus an intriguing way to allow a dealer to help an owner part with vastly larger sums of his money v. extended control arms, especially if co. engineers could not have even envisioned such a practical fix. Then again, there'd be that hailstorm of lawsuits for every wreck under the sun if the maufacturer had approved that mod without years of testing and certification tests and federal re-approvals..... lol

I'm immediately drawn to a number of issues with how that 3/4" slide might generates steering line bind with column or dash, or motor-to-firewall hard point clearance issues. The off-angle shocks are one by-product of any extended arm installation, so at least that would not be any worse with scooting the body forward. But thanks for the background.
 

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Back to thread related: the most important reason again that this part will NOT work under any B- or D- body is there's nowhere to mount a swaybar. Therefore useless, unless using (I think) the Trailblazer or some later-discoverd FOMOCO type bar mod that mounts firectly to the frame and the axle housing.

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The Speed Tech rear bar does not mount to the control arms - it mounts to the rear rend itself and up to the frame on the end links - Much like the Crown Vic's

 

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I just found these on RockAuto listed for the Fleetwood commercial chassis:

MEVOTECH CMS501006 Control Arm | RockAuto

Is this a thing?
I'm sure somebody already noticed, but that is an adjustable panhard bar to properly center the rear axle. It would be useful on a b-body that has a fixed length panhard bar in order to center the axle when the car is raised or lowered beyond factory specs. It's too bad nobody makes a watts link for the rear as it is a much better design that prevents the axle from traveling in an arc to just straight up and down.

Steve
 

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I'm sure somebody already noticed, but that is an adjustable panhard bar to properly center the rear axle. It would be useful on a b-body that has a fixed length panhard bar in order to center the axle when the car is raised or lowered beyond factory specs. It's too bad nobody makes a watts link for the rear as it is a much better design that prevents the axle from traveling in an arc to just straight up and down.

Steve
Sorry but it is NOT a panhard rod! If you cross reference the other parts numbers you will come up with :
"ARM. Rear Axle Control Arm" So feel free to guess again.

Mike--94MSP9C1
 

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To pile on , restating the obvious.
The rock auto listing is incorrect, that part has nothing to do with the full size rear wheel drive car.

The service bulletin I remember was to deal with one rear lower control arm mounting hole being mispunched slightly.
This resulted in one wheel being SLIGHTLY mispostioned front to rear.

The mis punch resulted in a tracking , unequal toe, thrust angle , dog tracking, call it what you will.
This was not the sideways axle to frame or frame to body difference that we have seen or THE VISUAL DEAL FROM THE 93 OPEN WHEEL WELL CHANGE making the rear wheels look too far ahead .
I will try and find the bulletin
 

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95wagon is correct, the TSB related to differences side to side in the rear wheel positioning. I don't believe there was ever a TSB regarding body/frame alignment but I did have the dealership correct the issue on my car back in 1997. The issue was the gap between the outside edge of the wheel and the fender where one side was larger than the other. Once adjusted the wheel gaps were the same side to side... the front to back centering would not be altered.
 

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Sorry but it is NOT a panhard rod! If you cross reference the other parts numbers you will come up with :
"ARM. Rear Axle Control Arm" So feel free to guess again.

Mike--94MSP9C1
Lol, the picture in the RA link the OP posted is in fact an adjustable panhard bar. I don't care what the part numbers say, so technically I'm not wrong. :p

Steve
 

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Well Steve,
What is the definition of a panhard bar?

Now explain how this lateral link that goes from the rear susp crossmember out to the bottom of the knuckle on a independent rear susp in a front wheel drive car could ever be called a pan hard bar.

A panhard bar, could be called a lateral link, sure.
BUT, just because an arm is a lateral link, that does not make it a pan hard bar.

The type of vehicle this link is made for has no solid axle to locate, so it really cant have a pan hard bar
 
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