Write-Up: Front/Rear (Addco) Stabilizer/Sway Bar Installation

Is the stock front swaybar diameter about 27mm on a 1997? I want to pick up the Energy Suspension bushings today. My OEM ones look oblong from years of abuse. I think might be what's causing the noise when I hit bumps on that side.

TIA!

-Rick


edit: I read someone posting 27mm on this site but that might have been the Addco one. On the net I'm seeing 1.02". Looks like that equals 26mm. I only see 25 or 27mm bars from Energy Suspension.

edit: Nevermind. Figured it out myself. Nice improvement over the stock bushings. I think a new bar is overkill if you can just put poly bushings into stiffen up the bar contact with the car.

DEMonte1997 wrote:

Nevermind. Figured it out myself. Nice improvement over the stock bushings. I think a new bar is overkill if you can just put poly bushings into stiffen up the bar contact with the car.

Rick, we'll have to meet up sometime. I'd like to compare yours and mine! Maybe at Bill's someday.

Sounds good to me Derek. I might be meeting up with him a few others very soon.

Wanted to give a heads up/warning. I purchased an Addco rear sway bar on Dec 26th 2009 through NeverEnough auto. I received an email a few weeks ago saying Addco is having problems meeting demands and all orders are backed up.
Then another email saying Addco will be drop shipping my order 1/13/10.
I got another email today saying it has been delayed (along with 78% of other addco bars) and will ship next monday.

Apparently all of the delay is on the part of addco, not never enough auto. Never Enough has been ontop of emails and has kept me updated throughout the process, but i'm still a little ticked off at addco for taking a month to make and ship a $150 piece of metal.

Never Enough is the only carrier of Addoc bars that fit our cars so just be ready to wait a long time to recieve everything. I know there were problems with the fist group order too, but i had hoped it was all sorted out now, a year or more later.
Never Enough is threatening to stop all carrying all addco bars if things dont improve, so if you wanted to get one, your time may be up.

Mr.Riviera wrote:

Never Enough is the only carrier of Addoc bars that fit our cars so just be ready to wait a long time to recieve everything. I know there were problems with the fist group order too, but i had hoped it was all sorted out now, a year or more later.
Never Enough is threatening to stop all carrying all addco bars if things dont improve, so if you wanted to get one, your time may be up.

When you say Neverenough is the only carrier, are you referring to your year car or all years.?
I got my Addco bar from Summit. They were having a sale and I had a coupon or some other discount coming to me at the time, so it ended being cheaper than neverenough.
Just need to plug the Addco P/N in Summit's search engine, (use Summit's prefix of ACO-XXXX and Addco's 4 digit number) and it comes up. But I don't think you can search by car.
But if Addco is back ordering, then it will be back ordered from Summit as well. I remember it took a month to get it. So Summit obviously didn't have it in stock and ordered direct from Addco and Addco drop shipped to me IIRC. I paid $125.00 shipped for the rear bar. ACO-2015 for my 1998.
The front bar for mine is an ACO-2018, in Summit's catalog it is not listed as fitting a Buick, but that is the correct one.

Yep, you should be able to purchase through any Addco dealer/reseller. Most auto parts stores can special order Addco. I had a great experience with Never Enough Auto on this purchase, but a terrible experience with Addco. It took them 3 shipments to get me the right front bar. The rear bar was okay, and included the necessary rear mounts. I'm not sure they include those rear mounts anymore.

i believe mine comes with a set of energy bushings and says to use the factory brackets due to the shape.
this is for the rear bar #2015. i paid 145 shipped btw.

I didnt know summit had them as well, but good to know if NEA stops orders from Addco.

Hey guys. This is what I have done ('98 SC). After some measuring and some research (I worked at a dealer), I found that the sway bars from a 2002-2004 Park Avenue Ultra with the optional F41 sport tuned suspension has the EXACT shape and length front and rear sway bars as the Riviera. The only things you would need to change are the bar brackets and bushings (which are poly-urethane). This changes your car to a 32mm front bar and a 22mm solid rear bar. I installed these last summer and WOW what a difference! I also bought a set of Energy suspension link bushings (JUST the bushings and spacers) and swapped the factory rubber ones with these. This gives you a perfectly clean install. All parts available from the dealer. If you cant find em, ask me and I'll locate them myself. Any questions just ask....

Please post the P/Ns... at least, as many P/Ns as you have. Some parts counter people might be daunted by the challenge of finding sway bars for an '04 PAU with F41 suspension.

It may amuse you to know that I put a PAU exhaust on my RIv - they actually made it for me at the Wixom plant about a month ago. Went on without too much fuss. The outlets end up at the far corners of the rear bumper fascia, kind of like the old Rivs with turndowns at the very rear corners.

Albertj


Albertj

I'd be interested in those P/N's as well.
We can order from on-line GM discount sources by P/N much easier than by application and maybe save some money.
I personally have already bought the rear from Addco and am looking at getting a junk yard front from an 00 Caddy STS w/FE3.
But if you have new P/N's I'll be very interested in what you have.

Np guys. I'll have to dig through my receipt box in my tool box tomorrow at work. If not, I'll call my old parts manager at the Buick dealer and get them for ya.

Ok guys, got em! They are as follows....

Front Sway Bar P/N# 25649664 = F41 sport tuned '97-2004 PAU

Rear Sway Bar P/N# 25650388 = F41 sport tuned '97-2004 PAU
Rear Insulators P/N# 25650389 (Qty 2)
Rear Clamp (bushing bracket) P/N# 25689592 (Qty 2)
Rear Link P/N# 25940977 (Qty 2)

I couldn't find the receipt for all the front bushings, brackets, etc, but I called my buddy at the Buick dealer to verify these numbers. I did not use the bushings that come with the new links....as I stated before I bought 2 packages of Energy Suspension Urethane bushings and spacers (I bought them at Pep Boys). The rear bar is gravy to install, the front, well, not so much as many of you know.
The difference in handling is awesome. The thing just flat turns without sacraficing too much ride quality....gives more of a sport feel. Any more Q's lemme know!!!!

Correction on the rear insulator P/N....apparently I have fat fingers..

Rear Insulator P/N 25650389 (Qty 2)

It looks like NeverEnoughAuto made it a little more convenient for us to get these sway bars. They aren't cheap but at least there is an easy method of getting them now.

Front Bar

Rear Bar

Abbadon (Scott) was telling us about some F41 (PA) Sway Bars that he installed on his car for quite a bit less than the Caddy Bar's.
He will reinforce what Im going to say about these bars being the same diameter as the caddy's and about, not quite, half the price of new ADDCO's and FE-3's and still available from GM along with High durometer bushing and End-Links.
I would suggest contacting him for part numbers.
I know I have the numbers written down here somewhere but I can't locate them right now.
I have looked at Monsterpartsonline for these and they are available and cheaper than tha Caddy stuff.
Worth a look.
Just another alternative.
I installed a Rear Addco bar from Summitt and been have very happy with the reduction of understeer. Not the complete elimination of understeer but a substantial reduction.
With that said I'm leery of putting a heavier sway bar on the front.
What will happen to the correction of understeer I've already made with the rear bar, if i put a heavier bar on the front.???

If you put a heavier bar in front, you'll get less body roll (that's where most of the weight is at). Worried the understeer correction will be lost? Use an even stiffer rear bar to get it back. Remember, the main point of anti-sway bars is to reduce roll, but they can also be used to dial in desired steer properties (preferably after roll is in check).

I feel it is worth noting the diameter of a stabilizer bar is only part of the stiffness equation. The thickness of the tube wall, and the material itself can make two bars of equal diameters behave quite differently. Only way to actually compare the Addco and GM F41 bars would be to test their torsion resistance using a machine or tool designed to do so. I think if one set up a jig and used a big torque wrench, noting movement, we could get some idea if how the bars compare. Use caution when using only diameter to judge a bar's performance.

I have no argument whatsoever regarding the effective measurement of one sway bar over another. It certainly can not be compared by outside diameter only, I agree.

But what I experience with the ADDCO rear bar ( in this somewhat stock configuration) is a reduction if not almost complete elimination of understeer from the front

So I've been slightly apprehensive as to what to do the front, without reversing the progress i made.

I also know all this will change once I put 18" wheels with much better tires on all around.

No doubt there was a reduction in understeer, however with the stock front bar I would think there is still a lot of body roll, which is going to affect overall traction in a hard corner. In other words, even though you're understeering less, you may not actually be holding the road with any more grip.

One way to test the effectiveness of suspension mods is to use an accelerometer to measure lateral G forces in a turn. I think the Riv was rated .78 lat G in stock form. with KYB front struts and MaxAir rears, and Addco front and rear bar kit, I've measured a .94 G on coming off an exit ramp - with stock wheels. I am a bit hesitant to change anything at this point.

If I may, How are you effectively measure the G force's, which will enable me to compare.?
Your .9 G's is quite impressive, how are you measuring it. With who's tool or accelerometer.

I use the ones built into the iPod/iPhone. It's easy to test the accuracy of an accelerometer. Set it flat (0º) and it should read 0.00 lat G, set it vertical to the ground (90º) and it should read 1.00 G. I use the Dynolicious app to measure lat Gs, also accel and decel Gs. More on accelerometers and iPod apps here:

https://rivperformance.editboard.com/audio-electronics-f7/automotive-apps-for-iphone-ipod-touch-t3707.htm

Can anyone speak for the addco bars being tighter than the F41 or even the FE2/3 bars? They are the same dimensions so someone would pretty much have to literally compare them either on the car or something like what AA described for a test. Has anyone experienced both kinds? Addco claims that their bars are tighter than any of the applications, including the cars with the FE2, etc bars so logically, that says the Addcos are the tightest but is there any more knowledge of this besides Addco's word?

I already have FE2 bars (rear installed - front waiting) but I want the tightest I can possibly get.

I don't know. But i have seen some large diameter GM Sway Bars that have broken under normal use, granted they were hollow bars and I'm not sure of the RPO code of the individual vehicles.
But I hang out at a shop down the street occasionally and have seen several GM Suv's as well as Caddy's with broken Sway Bar's.
I guess I should have looked for the RPO codes on them to see, but I haven't.
But based on what i have seen, and the fact that these Addco bars are solid and not much more money than OEM, I think I'll try the Addco on the front.
Already have one on the back that I bought through Summit's Web site with no break on shipping.

Abaddon, is the GM front bar solid as well?

Do we know that the GM bars are not actually the same bars as Addco?

The front Addco bar likely isn't solid. It's larger and hollow to reduce weight and provide the same torsion resistance rate as a smaller but heavier, solid equivalent. Most front bars are hollow for this reason: to provide the highest torsion rate with the lowest weight. The rear bar is solid, resulting in heavier weight for its torsion rate. This further supports the idea of having less weight up front, more in back, for more ideal weight distribution.

Before someone suggests it, the above facts do not mean the front bar is lighter than the rear one, it only means each bar is engineered to be lighter or heavier for its torsion rate, the rear having a lower rate.