2008 cracked upper rear control arms

[Tom, F&L GoR]

Has anyone seen this? It's a 2008 daily driver with 60K miles, a rear shock went bad so I replaced all four with BC coilovers. While driving / measuring fender gap / adjusting heights, I found this crack in the right rear upper arm. It is so obvious that I think it has happened during the last hundred miles while I am adjusting ride height. The car is slightly lower, but not bottoming, so I am not considering the shocks (it's the upper arm anyway, the shock/spring attaches to the lower arm.) There have been no accidents or pot holes. I see the part number suffix has changed all the way to "AE" so wondering what the improvements have been.

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[SRT_BluByU]

wow - thats a scary picture.. in my opinion i think you might be correct in that its pretty fresh looking..

[Tom, F&L GoR]

Lesson learned - if you search for "2008 Dodge Viper control arm" you get many eBay parts recyclers and the cost is ~$200 - $500. Dealers are up to $1000. Search by part number 05290117 and I found https://www.partsworld-uk.com/produc...ge-viper-srt10 who has one brand new one left. Was £869.64 ($1020) and on sale for £45.99 ($54). Since I'm not in the UK, they took away the VAT and it's £38.33 plus £19.99 shipping, so a total of $68 to my door. Funny, but not funny.

[Viper98]

First, WOW! And good catch. That’s kinda weird. Is that where the Gen 3 and Gen 4 A-arms are gunna crack? Maybe it’s time for the Gen3/4 guys to take a look. Gen 2 control arms crack underneath. Rigs are gettin old fellas. Time will tell.

Second, if you got that whole part (w/ bushings) to your door for $68.00 I’d say you STOLE that part. Good job, mang!

[J TNT]

There have been a few posts on the issue Tom , at the Bushing end by the frame . One School of thought is the metal corrodes , expands and cracks the aluminum . I try to check mine once or twice a year .

[Tom, F&L GoR]

Yes, Jay, the aluminum corroded badly. I took the arm off and pictures below are the threaded hole the ball joint screws in to. I was very, very lucky guys. The outward side had cracked through (I can flex it with my feeble biceps) and the inward side was also cracking.

I wish I could provide some guidance, but the only view of a crack would be that outward facing section. Otherwise, it resides under the lip of the ball joint on the top and the rubber boot hides it on the bottom.

I overcorrected and bought (hopefully) the new one from the UK and a used one on eBay since I haven't looked at the left side yet. If anyone wants the next best deal, there is another one on eBay from the same seller, but it needs bushings and a new boot for $139.99. Since I'm watching, I received an offer for $125.99.

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[Tom, F&L GoR]

Viper 98, I'm expecting new bushings and new ball joint!

[VIPER BAZ UK]

We have had a few break here in the U.K. . Seems to be corrosion in between the two metals then expanding and cracking.
Great spot and save. Could of be a very different outcome.

This scares me on my 09 especially with parts getting hard to get.

There is a guy in France who does CNC billet ones.

[GTS Dean]

Wow Tom! Those are some grimy looking wishbones and rusty ball joints. Have you had the car since new? You drive your cars quite a bit, even in winter too, right? I'd lay heavy odds on de-icing road splash having a lot to do with that.

[Tom, F&L GoR]

Hi Dean. I've owned it since early 2019 when it had 30K, now it has 60K despite COVID and a lot of working from home. I try to avoid wet winter days, but who knows. I've had aluminum wheels leak air at the bead due to the same white powder, everyone remembers the Gen 1-2 side sill attaching screws would cause corrosion, and even Carrol Shelby's Cobras would corroded where the aluminum body attached to the steel frame. Maybe winter driving doesn't help, but if the aluminum isn't properly treated or the dissimilar metals aren't insulated, it's probably going to happen.

All these pictures and nobody commented on my brand new BC Coilovers. So much for shiny things!

PS thank all you folks taking good care of my next Viper.

[ViperSRT]

Interesting Tom. Based on the photos and degree of corrosion I am wondering if you live in a region that uses magnesium chloride as a deicer (and the UK guys as well). I have read that magnesium chloride attacks aluminum quite readily, especially at elevated temperatures (which in the vicinity of the brake components is certainly possible). Just a thought.

[Tom, F&L GoR]

Yes, I have driven in cold weather with that dried out white film of snow melt on the road. But, I've only had the car since 2019 and before that it was owned by someone in Montana (where their LLC used it as a track car) and then someone in California. It was retired from that life, freshened up by a Viper collector in the south that I know, and now lives here. I'm sure there are "winter cars" with aluminum suspension arms and steel ball joints that do fine. My Gen 1 had 146,000 miles between owner #1 in Montreal and owner #2 (me) in NY, and while there were other issues, A-arm corrosion or cracking was not one of them.

I am not surprised at the corrosion - it will happen. Better coatings might help there. I am surprised at the cracks because I don't believe the corrosion added hoop stress to split open the threaded hole, or that the corrosion preferentially created cracks nearly in line with the outboard and inboard direction, which happen to be the thinnest walls around the threaded hole. The ball joint was not super hard to unscrew, so couldn't be "growing larger" but maybe it was simply coming loose? Perhaps the UK colleagues can chime in with some details of their experience - hopefully more "before it happened" stories than "after."

[Tom, F&L GoR]

Any comments about re-tightening ball joints in the a-arm? That would cut through the corrosion and prevent the ball joint from loosening and rocking. I might try this when I get to the other side.

[Old School]

Once that arm splits, the ball joint is not going to be screwed it tight anymore.

[GTS Dean]

it was owned by someone in Montana (where their LLC used it as a track car) and then someone in California. It was retired from that life, freshened up by a Viper collector in the south that I know, and now lives here. My Gen 1 had 146,000 miles between owner #1 in Montreal and owner #2 (me) in NY, and while there were other issues, A-arm corrosion or cracking was not one of them.

The Gen 1 arms were all made from high strength steel, then hot-dip galvanized.

I am not surprised at the corrosion - it will happen. Better coatings might help there. I am surprised at the cracks because I don't believe the corrosion added hoop stress to split open the threaded hole, or that the corrosion preferentially created cracks nearly in line with the outboard and inboard direction, which happen to be the thinnest walls around the threaded hole.

I think the key here is that it was a dedicated track car in its early life. With the lateral G's these cars can produce on R's or slicks, that puts a lot of moment on the upper ball joints normal to the car's centerline. Even if the ball joint sockets elongated just a tiny amount, it could have opened up just enough for road spray to enter. Eventually the corrosion caused a stress fracture through the thinnest section. Who knows - perhaps brake pad material could be a factor as well?

[Tom, F&L GoR]

Old School, I meant tighten them as a preventative measure so if corrosion loosened them, at least they would not rock or rattle and stress the arm. Once it splits, the car sits.

[Old School]

Old School, I meant tighten them as a preventative measure so if corrosion loosened them, at least they would not rock or rattle and stress the arm. Once it splits, the car sits.

What I meant is, once it's split, you can't tell which came first, loose or split. It could have been caused by rocking or corrosion expansion.

[Fatboy 18]

https://driveviper.com/forums/thread...ERIOUS+WARNING