S65-M3

2007 with 70K miles. All stock except CDV got removed by previous owner.

I just bought this car and noticed very bad vibration while accelerating. I researched this and found Inner CV joint could be the cause. I made the swap yesterday and did notice driver's side is pitted badly.

My question is since my car has always been on stock suspension and only it has 70K miles is the CDV removal the cause of this issue?

I asked some local indy's in my area and they said they are surprised to see a stock AP2 with 70K that has this issue.

Should I install the CDV again so that I don't face this problem again after the swap? Because I don't see any other reason that could have caused this issue. I trust the previous owner as he is a friend and no modification was ever done on suspension

engifineer

Hard launches are a big cause of this, so I would think maybe the CDV could help a little in that use case. Not sure how much though. Lowering the car can cause the vibration if the cups have a lot of wear and you move the axle so the bearings are running on the edge of that wear, however, the visible pitting is very likely just caused by hard impacts like a hard launch. That damage is very different in nature than wear. It is actually chunks broken out of the CV bucket.

seoulbro

The CDV definitely helps with prolonging the life of the clutch and maybe some other parts. If the previous owner turned the VSA off often to do power slides or donuts, that certainly can cause premature wear on the axles. Of course, hard launches without the CDV can do some damage as well. Are you sure the car was never lowered? That can cause the wear especially if you're not using spacers.

cosmomiller

I have heard from some knowledgeable folks here on the forum that replacing an OEM hollow axle with a solid aftermarket one can cause vibration. Any chance the axles were replaced?

engifineer

I have heard the same and definitely a good quetstion

S65-M3

Everything is stock on my car except CDV. As I mentioned in my OP, the vibration was completely gone after the CV cup swap. I am just wondering if there is a solution to this because I really hated doing that DIY and not looking for doing it again.

IF it is clear that CDV removal was the cause of this, then I will definitely install it back and life with it as long as I don't have a pitted CV cup after some mileage on it.

engifineer

From discussions on other threads, some shared info today of the same exact failure (pitting) happening on their Acura as well that has never been driven hard, but is lowered. So I think the impact of hard launching has to play into it, but a lot worse if the car has been lowered and the axles are at angles other than stock. So this tells me you likely will not avoid it. I also know that AP2's have the same issue as well (AP1's do not have the CDV) but not sure if it is more often with the CDV removed or not. Maybe others will reply if their AP2 had it happen with or without the delay valve.

As a note, if the biggest pain for you was the axle nut, you can do the bucket swap completely on the car without removing the axles. Pop the lower rear balljoint, remove bolts holding axle to diff, pull out of diff (popping the ball joint allows that movement) and you can disassemble it under the car with the axle nut still in place. It can be messier dealing with the grease and stuff under the car, but does remove dealing with the axle nut, which if it has been re-tq'd,sometimes does not want to come loose even with an enormous breaker bar. Just FYI there. Doing it that way I can swap cups in about 30 min.

S65-M3

30 min?? that's fantastic. Actually I didn't remove the axle nut (even though I have the tools). I went with just disconnecting the ball joint to allow more play and it took me 7 hours (no kidding) just because I wanted to be extra careful.
However, the pain was the mess I made on the car and ground (I know this is relative). It was a complete mess for me and not to mention the amount of cuts my hand got from removing the cups (even though I changed my disposable gloves 6 times), I still left scratches on my fingers/hand.

I usually do alot of DIYs on my ars and this was very messy with lots cuts compared to others i have done. Even though it is not difficult DIY to do to be honest.

engifineer

The mess is the worst part for sure. That grease gets everywhere, even if you just stand there looking at it lol.

Car Analogy

It seems logical that with cdv removed hard launches are harder.

Conclusion, cdv does not directly cause the issue, but can exacerbate the effects of abuse behaviors.

Thus if you aren't going to conduct regular abusive behavior, leaving the cdv off should not contribute in any significant way to pitting.