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What are these adjustable tubular things for $25?

3K views 30 replies 11 participants last post by  Caddylack 
#1 ·
#5 ·
About the right length and mounts for a LCA. But you'd never get a stab bar on it. A call can clear things up:

 
#6 ·
It almost has to be.
 
#7 ·
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.
 
#10 ·
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.
 
#9 ·
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.
 
#11 · (Edited)
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 …
 
#12 ·
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.
 
#14 ·
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
 
#15 ·
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
 
#16 ·
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
 
#17 ·
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.
 
#20 ·
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
 
#23 ·
"
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"


FAYS2 makes a "hotrod" watts link kit with your supplied measurements that would only require minimal welding. I keep thinking about doing this but my concerns are

A) my chassis is already painted, gas tank in, car is almost fully back together and after 13 years of building it the idea of taking things apart again doesn't excite me

B) not sure I want to add more weight to an already pig heavy car. LSX iron block, LSA supercharger, trunk mounted 7 gallon water tank, boxed chassis, 1 3/4 .090 wall "DMR" bar, Dynamat etc... I've already added a ton of weight to the heavy pig

What I do like about the watts link is I think it would greatly reduce bind in the triangulated 4 link setup because the upper arms should never see any side load. IT would probably actually be best to run a parallel 4 link but now you are talking about some major modifications to the chassis and rear to correct the upper arm angle. In theory though, if the watts link is taking on all of the side load, the upper control arm bushings will now only see load from one direction (to maintain pinion angle) and I would think this would help a setup with a one side delrin/poly or double sided deleon/poly bushings move through their range of motion smoother without bind.
 
#25 ·
No personal knowledge, just some threads on it years back. Either or both the Panther and TBSS (or maybe other sizes on TB) conveniently bolt the end links to existing unused (?but enlarged?) frame holes. And then just muffler clamps to the axle visually sim. to the Speed Tech setup. Reported advantages are not required to either box exist. LCAs or replace them, less wt. than the biggest regular aftermarket sway bars, and less torsional stress on both LCAs and UCAs.
 
#26 ·
The reason I asked is I have searched this forum for Trailblazer info in the past, and came up with nothing. I've definitely heard about the CV rear bar before, but I have no idea how the b-body frame compares to that of a TB.

If anybody is able to dig up a thread or two, that would be sweet.
 
#27 ·
Search brings up nothing for me either, but I'm sure you've seen this one referencing the Speed Tech, CV, and even the 'Chevelle Bar'.

I'm 'Conversation'-ing someone who may be able to help......
 
#28 · (Edited)
The OP asks whether the $25 part is "viable" to serve any function on a B/D chassis. There are people that have created a panhard for this chassis, however, the standard 4-link with upper & lower arms at opposing angles provides centering laterally by it's design. Perhaps it could be "repurposed" - just doubt it would produce any benefit other than to band-aid another part that has failed or is not working as designed.

Adding a panhard creates a forced motion/travel path that is actually going to restrict motion/articulation of the 4-link design - ie. binding. Only the fact that the ends of this part are rubber would reduce that tendency, but being rubber also make the part useless as an active suspension locating device when that has already been dealt with through the upper control arms.

The application listing (Buyers Guide) for this part is corrupted, and it is not a part made for the 4-link B/D chassis. The vehicles it actually fits are FWD, and the part from Mevotech is replacement for OEM links, of which there are 2, one for each side/rear wheel, locating the rear hubs (IRS) laterally. The adjustability feature is for wheel alignment purposes.

A panhard bar is essential in a 3-link setup, and is found on cars with a torque-arm, such as Gen3/4 Camaro, to provide lateral rear axle location.
 
#29 ·
This is an odd listing at SpeedTech, no picture, not clear what "frame mount" is referring to - links or bar Factory Style Mount Sway Bars

Only $299.00​
SKU: 233507

Description:
Frame mount 7/8" Adjustable Sway Bar, Reqired for use with Speedtech Trailing Arms

More here about 4-link, panhard, S/T Articulink, etc: Why is Speedtech's 4-link Superior?
 
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