Ahhh, they are AP1 diffs you are blowing... Didn't Honda update the AP2 diff??? Not saying that the AP1 diffs are bad, just not as strong.

I have done burnouts, doughnuts and launch from stop lights occasionally so you could say I drive my car spiritedly then some. No problems here though (just over 50k). I do change my diff fluid with LE every 10k or less. I removed my CDV at about 25k but my clutch will still slip a bit if I am too hard on it.

I know S2k owners who drive as hard or harder than me and have also been problem free (AP1s and AP2s). I’ve only read posts about continued diff failures though, nobody that I know personally. I’m not saying it doesn’t happen, especially with older S2ks that are heavily modded and/or regularly raced on the street or the track. I wouldn’t say the S2k has a “fragile” diff when driven spiritedly though (the AP2 even less so).

As a few others have suggested, you can probably just chalk your diff issues up to bad luck and the quality of the rebuilds you are getting. Hope you get a solid diff the next time around.

 

there is a direct correlation between thicker fluid and less wear on the diffs in hot weather conditions. I would definitely recommend 75w140 Amsoil Severe Gear, or possilby 75w140 Redline, or one of the LE fluids. I'm running 75w110 Asmoil Severe Gear, but I drive my car very easy and slow most of the time, I'm considering going up to 75w140 SG. I wouldn't run 75w90 on your car anymore. Just my opinion.

 

Thanks for all the suggestions.

Like I said earlier, I do all the work on my own car, from engine and transmission work to tire installs. No one touches my car but me. I highly doubt bad installs are the cause for this. I switched to an AP1 driveshaft and tranny output flange to fit the AP1 diff correctly. No vibrations or weird behavior of any sort except for some vibration last year due to a driver's side axle having a severely pitted bucket. If anyone can point out where a mess up can happen installing a diff on its original position while marking all the stuff before removing it, I'd like to know. (not being sarcastic)

JFUSION, I spoke with Puddaddy a few days after this and he said that the correct fluid for our diff should be 75W140 due to the change in oil classifications in 2007. He said that's a likely cause for my repeated diff failures, and should consider switching oils.

Lastly, I see other car makes with abusive driving make it well over 150k miles and the differential is still fine, like most BMWs that I have come across. Here you have a car that is made fun of for being torqueless and it blows diffs all the time. For every person here that claims that their diff is holding 100k miles with track days and abusive driving, there's another who drives like grandma and has their shizzie blow up rather early.. so what's the point? lol

 

Maybe the new diff with the newer fluid will last you longer. Is there any reason you didn't stick with an AP2 diff? If it failed at 44k shouldn't it have still been under factory warrenty?

Different parts on different cars fail. Nonetheless, most models from pretty much all makes have their issues. You are crazy if you think BMWs have not had their issues (or any other manufacturer for that matter). The failures may be in different areas but they still occur. Just to name a few using your example, the last M3 had an engine that liked to implode and the Z3 M coupe had its issues with the diff mounts failing. I'm not cutting on BMW, I'm just using them as an example because you did. We could pick any car and if you search their forums you will find problems specific to it.

In the case of the S2k, the diff has been known to fail but the occurrences of it failing are seldom due to normal driving. Go ask your Honda service department how many S2k diffs they replace under warranty (50k miles or less). It happens but it's not nearly as common as you think. Clearly they do fail, a quick search of this forum will prove that and Honda did make some changes for the AP2 so clearly they saw something too… I just don't think S2k diff failures are an epidemic.

Someone please get this guy a solid diff so he can continue enjoying his life.

 

^ That's good insight, thank you.
M3 with an imploding engine? that's almost as scary as the dreaded #4 piston wall issue lol.

As a funny note, I'm already working on getting a very cheap AP1 diff with 50k miles just to get the car on the road until I'm able to save enough for a brand new rebuild.. let's see how long this one holds up.

Pics of the damage coming up.

 

pics up as promised:

 

have you thought with going with a diff. gear set. maybe a 4.44 or a 4.56?