105 upper A arm inner bushing problem

[1166]

You all do not NEED to replace the upper bushings with lower control arm bushings. SOME of the adj upper arms I have bought have BONDED rubber bushings - which look fine to me. This is a 'new' thing I have seen in the last year or so, on about 1/2 the arms I have gotten. The bushings have 'FRAP' molded in them. Stock Alfa upper bushings are bonded and are perfectly fine to use (this is what I use). If the adj arms have the pressed together bushings, well, you know what to do... The replacement rubber bushings from the various suppliers should be fine - just as long as they are bonded.

The original lower bushing were made differently than the ones of today. The old ones had seals staked on both sides of the bushing. The arms did not have 'dustcaps'. The 'new' style lower bushings are designed to 'be around' grease, hence the caps on the end of the arms and the seals on the other side. I cannot comment on how long they will last unprotected and ungreased. Probably a long time, but I suspect the stock rubber will last longer and give less problem. Now if you drive very little and don't use it in the wet, etc, they'll last 'forever'. Since I drive on the street and generally just have fun, I will use the rubber bushings. It won't matter one bit for me, and I suspect most people here couldn't feel the difference in normal use. I am not suggesting anyone use or not use them, I am just offering extra information to think about!

[msiert]

Quote:

Originally Posted by 1166 Stock Alfa upper bushings are bonded and are perfectly fine to use. If the adj arms have the pressed together bushings, well, you know what to do... The replacement rubber bushings from the various suppliers should be fine - just as long as they are bonded.

[Gubi]

Quote:

Originally Posted by msiert How do you know forsure if the rubber is bonded?

[msiert]

Quote:

Originally Posted by Gubi From my experience, you put it in your car. If it oozes out, it's not bonded. Did I mention this sucks? This sucks.

[1166]

Wow, you guys are on top of things. If I can figure out where I put my arms I will take a pic of them. Don't wait for it! It will probebly take a few days... The bonded bushing says FRAP on it and the rubber is lower (by about 1-2mm) than the inner sleeve and the outer sleeve. The pressed bushings rubber is about even with the sleeves and it does not have FRAP cast into it. Of course, you will get one cast and one pressed when you buy the arms!

[msiert]

Quote:

Originally Posted by 1166 Wow, you guys are on top of things. If I can figure out where I put my arms I will take a pic of them. Don't wait for it! It will probebly take a few days... The bonded bushing says FRAP on it and the rubber is lower (by about 1-2mm) than the inner sleeve and the outer sleeve. The pressed bushings rubber is about even with the sleeves and it does not have FRAP cast into it. Of course, you will get one cast and one pressed when you buy the arms!

[1166]

They look bonded. I am ONLY talking about the upper inner A arm bushing. You might want to check Alfa Stop in the UK to see if they have some 'alfastop' manufactured trailing arm bushes for Montreal for a performance bushing. Or you could install heim joints in the trailing arms... I got some OE Alfa trailing arm bushes a while ago and they looked crummy as compared to what they USED to look like.

[Andrew]

The rubber-bushing upper arms that are failing are new aftermarket, not 20-year-old NOS Alfa parts. Brand new from CL or IAP; just not well designed or made.

Andrew

[gprocket]

Allow me to jump in here and offer some comments. I have not yet experienced the issues you guys are reporting but I can well imagine that it is the wild west with most of the rubber suspension parts.

I am in the rubber molding business and I know from first hand experience what happens. The OEM bushings are the best quality because the drawings are very specific about the type of rubber and its performance characteristics. Twenty, thirty, forty years later, the aftermarket manufacturer will be handed a bushing and told to "make this". The problem is that there are literally millions of rubber formulations and it is quite unlikely that without the drawing and specifications that the correct rubber will be used. That said, a legitimate rubber molder should be able to know what would be the logical (not necessarily the optimal) rubber to use. But so many of these bushings are now made offshore in China and India. No disrespect to these guys but they don't have the experience to know what to use and their customer is not specifying it. So they use whatever they have. And of course they are sourced there for their low cost. What is generally missing from the cost equation (beyond the obvious labor rate differential) is the performance testing. Shoot and ship is the name of the game in this case.

As to the concerns over pressed in bushings verses bonded ones, done properly a pressed in bushing is many times preferable. Think of it this way: If you think of rubber as a spring (actually a spring/damper but that's a discussion for another day) you would never design a spring assembly without the spring in some state of compression. Otherwise the spring would flop around, the assembly would be sloppy and excessive wear would result.

Same thing with rubber. By press fitting (or shooting as its called) the bushing into the case, you are compressing the "spring" and eliminating the initial slop. Sometimes you mold/bond the rubber to the inner sleeve and press the assembly into the outer case. Sometimes you mold the rubber separately and press both the inner and outer metals.

The cheapest and easiest way to make a bushing is to "bond" the rubber as in the pictures above. Actually what is happening here is that a bonding adhesive is applied to the inner and outer surfaces of the tubes and the rubber is injected into the cavity. The rubber is vulcanized and bonded to the metal all in one step. The problem with this is that the rubber is in a relaxed state rather than compressed. When assembled and weight applied, the bushing will immediately go off center and ultimately wear out quicker than a properly designed "shot" bushing.

None of this helps with the problem at hand but might help to shed light on the situation. If I had the tooling (which I don't) I would and could make the correct bushings all day long. But the economics just aren't there...

[msiert]

Sounds like replacing the inner camber arm rubber bushing with the bottom a-arm spherical bearings is the way to go for me.

Thanks for the great write up, Rich!!!

[Andrew]

Centerline and Jon Norman both recommend replacing the rubber inner upper bushing with the lower A-arm bushing before use, though I seem not to have gotten that message when I bought mine a few years ago.
Andrew

[msiert]

Quote:

Originally Posted by Andrew Centerline and Jon Norman both recommend replacing the rubber inner upper bushing with the lower A-arm bushing before use, though I seem not to have gotten that message when I bought mine a few years ago. Andrew

[velocedoc]

I would prefer to use the bushings in the upper part of the picture as if I am reading this thread correctly. This makes the bushing a royal pain to get out of the suspension box it is installed into. I wouldn't think that the lower bushing would be so bad to use, as I do understand that gpsprocket is saying, it is just the fact that the bushing migrates over time and wedged the upper arm into the box. Hence the cutting and other issues that have been discussed. If there are no issues with the lower A arm bushing being installed, then I would go that way and never consider having to replace that bushing again. It certainly isn't having the loads imposed on it as it would be in the lower arm.

[Andrew]

Yes, that's what this post is all about. The unbonded rubber in the stock inner bushing migrates fore or aft, reducing effectiveness, and trapping the inner end of the arm in the box on the collars.

Andrew

[Cintos]

Quote:

Originally Posted by Andrew Centerline and Jon Norman both recommend replacing the rubber inner upper bushing with the lower A-arm bushing before use, though I seem not to have gotten that message when I bought mine a few years ago. Andrew