Well, I havent driven my X in a week, leave for SC and come back to find my X in a puddle of metallic gear oil. Jack her up, remove under panel and voila there is a crack/hole in my diff. What is weird is that I never heard any wining or anything. I would have never known if I didn't see the oil under my car.

What sucks is that I JUST did my clutch about a month ago so I have to go back in to replace this shit. I don't think there was any damage done to the diff or trans, just the casing.

What is the best way to go about correcting this?

While I am in there (again) I would like to upgrade something to make it worth-while. Thought about doing the final drive and bearings but not sure if it's worth it.

(Discuss)


http://www.evoxforums.com/forums/attachment.php?attachmentid=21097&d=1300050300

Shep offers a diff rebuild/upgrade. You'll need to get it welded/"repaired" anyways.

http://wedontlikeu.com/images/car/EvoX/StrokerBuild2010/transmission/Shep1Blank.jpg

Holy shit it's FREE!!! lol

haha :p

You can probably also just have any local shops replace the pins, and weld the thing up, but since you have to do SOMETHING, might as well "upgrade" it as much as possible.

After reading some articals from Jacks Trans and Shep it looks like the pins aren't entirely the problem, it is more of a lubrication issue. I don't want to do this again so I wanna do it right the first time.

After reading some articals from Jacks Trans and Shep it looks like the pins aren't entirely the problem, it is more of a lubrication issue. I don't want to do this again so I wanna do it right the first time.



This^... The write up from Jack's is spot on, and I suspect due to tolerance differences between spider gears and the pins, certain evos fail before others. I'm sure launching doesn't help, but the lube issue is the main cause. I'd talk to them, as they were very reasonable for my upgrades. :rock:

it was $100 for shep to weld mine, along with $600 for another diff

Dam man sorry to hear

Well, I havent driven my X in a week, leave for SC and come back to find my X in a puddle of metallic gear oil. Jack her up, remove under panel and voila there is a crack/hole in my diff. What is weird is that I never heard any wining or anything. I would have never known if I didn't see the oil under my car.

What sucks is that I JUST did my clutch about a month ago so I have to go back in to replace this shit. I don't think there was any damage done to the diff or trans, just the casing.

What is the best way to go about correcting this?

While I am in there (again) I would like to upgrade something to make it worth-while. Thought about doing the final drive and bearings but not sure if it's worth it.

(Discuss)


http://www.evoxforums.com/forums/attachment.php?attachmentid=21097&d=1300050300

Man the same thing happened to me about 2 weeks ago. The dealer denied my warranty.

is your evo an 08 or a 10?

why is there a difference on how they make the pins?

got a link to the article you were talking about? was it this one: http://www.jackstransmissions.com/pages/evox-review

I can't think of anything else thats internal to the trans that would be wroth 'upgrading'. final drive gear isn't that big of a deal but is a pretty big chunk of change.

The best bet to get a rock solid trans/diff seem to be getting the obvious problems eliminated, not just repaired. Having shep or jacks do the work would be great, but it'd obviously be a bit more down time and probably some shipping unless you can find someone local.

According to JackM, it makes sense that you would see these problems. "The way the assembly is designed is flawed in that the faster you drive your car the less oil is able to get inside." Being you drive long highway trips every day, you're at high speed and thus starving the gears of oil during the trip.

Jack says this is a nearly identical problem as the one in the DSM diff. You might want to get a hold of Greg from UCS Performance in Beltsville since he's local. He's a huge DSM guy... that's all his shop works on. See if he's familiar and if you'd be comfortable having him do the job. His cell is 240-271-0280. He's also next door to Infinite Speed & Performance, who's another really good evo8/9 and DSM shop.... with an AWD dyno :)

is your evo an 08 or a 10?

I have a 2008 EVO X

The addendum to the Jack's article is disturbing. I obviously run high speeds on the road course. hmpf.

is your evo an 08 or a 10?

2010

@Decepticon - What is weird is that when I looked at your picture I was like...wtf thats EXACTLY the same picture I took... FUCK! :duh:

I HIGHLY doubt there's any differences between the 2010 and 2008 differentials. Any "fixes" would be internal, and specific to this issue.

I read a thread about them changing the material used in the pins. (Seems pointless to me to change the material) but oh well...

just fyi for 2011 owners, I sent my diff into shep for the pin and torrington bearing upgrade, and he said the pins were updated to the better ones. So technically 2011 evo pins should be fine.

I still had them do the torrington bearing upgrade since they already had the diff.

Of course this is speculation, but what I have gathered from this discussion in other threads is Mitsubishi started adding a heat coating like they used to do on the older differentials.

Which makes sense because that is the cheap and easy fix to the lack of lubrication problem.

"If we can't fix the heat problem caused by lack of lube... we will make the part more resistant to heat!"

This thread is WIN. I've read a lot on this and it was still vague.

there are three schools of thought on this:

the pinion shaft roll pin breaks because it moves too much, so weld it in place to prevent it from moving
the pinion shaft pin breaks because it's not made of the correct metal, so replace it with a harder pin
the pinion shaft pin breaks because it moves too much, so improve oil flow so it moves less


I think the last option makes the most sense. If you can reduce the shaft pickup from the pinion gears, then the pin will move less (fixing 1st problem), thus preventing it from wearing so fast (removing need to fix 2nd problem). But upgrading the pins still sounds like a good idea imo.

Read this thread by JackM of jackstrans: http://forums.jackstransmissions.com/viewtopic.php?f=17&t=212

As for welding them... I think this might be a good quick fix, but since it doesn't address the root cause, it might just be transferring failure to the next weakest point. If the pinion gear is picking up the shaft, and you weld the shaft in place, then that pick-up will result in wear between the shaft and the pinion gear. Over time, this will cause the gear to wobble. When it's engaged and wobbling, it'll eventually wear out the other gears, resulting in total diff failure. Does that seem right? It might prolong the failure, but it would make it worse. Instead of having to replace pins once in a while, you have to replace the entire diff. yikes!

2010

@Decepticon - What is weird is that when I looked at your picture I was like...wtf thats EXACTLY the same picture I took... FUCK! :duh:

Thats the same thing I said...I thought you copied and paste it jk lol...

Here are some interesting posts on evom in regard to the materials used for the diff pins. The guy at least sounds like he knows what he's talking about ;) Read the posts by CliveW.

http://forums.evolutionm.net/8238827-post37.html

there are three schools of thought on this:
the pinion shaft roll pin breaks because it moves too much, so weld it in place to prevent it from moving
the pinion shaft pin breaks because it's not made of the correct metal, so replace it with a harder pin
the pinion shaft pin breaks because it moves too much, so improve oil flow so it moves less

I think the last option makes the most sense. If you can reduce the shaft pickup from the pinion gears, then the pin will move less (fixing 1st problem), thus preventing it from wearing so fast (removing need to fix 2nd problem). But upgrading the pins still sounds like a good idea imo.

Read this thread by JackM of jackstrans: http://forums.jackstransmissions.com/viewtopic.php?f=17&t=212

As for welding them... I think this might be a good quick fix, but since it doesn't address the root cause, it might just be transferring failure to the next weakest point. If the pinion gear is picking up the shaft, and you weld the shaft in place, then that pick-up will result in wear between the shaft and the pinion gear. Over time, this will cause the gear to wobble. When it's engaged and wobbling, it'll eventually wear out the other gears, resulting in total diff failure. Does that seem right? It might prolong the failure, but it would make it worse. Instead of having to replace pins once in a while, you have to replace the entire diff. yikes!

From what I read it was more of a lubrication issue while under high constant speeds starving the diff of fluid thus increasing heat and causing the various parts to fail.

Here is the update to his review:
Most people are only replacing the pins when repairing/upgrading your X center diff. This will not work! The reason the diff pins fail is due to a lubrication issue. The gears don't have enough oil, so they seize to the shafts which break the pins as the twisting force applied to the pins is more than they can eventually take. Basically, the seized gear will twist the locking pin right off the shaft. Upgraded pins will delay the failure of the shafts working their way through your case, but WILL NOT solve the lubrication issue. What we do is tear the whole center diff down. We modify the shafts to allow for more oil, we upgrade the pins for added insurance, and we then add scoops to the center diff housing to force more oil inside the assembly. The way the assembly is designed is flawed in that the faster you drive your car the less oil is able to get inside. Our scoops will force more oil in the assembly the faster you go and it works! Some info HERE on how we do it (the link is of what we do to a DSM center diff, but it also has the same issue and your X center will get the same treatment)

Thats the same thing I said...I thought you copied and paste it jk lol...

Said the same thing lol

Yeah, it'd be dumb not to fix the lube issues in the process. I'm getting mine done, and having the fluid scoops added too.

Same here.

Does Shepherd do the same things as Jacks Trans?

whats it costing you stock? pm me, just for future references i would like to put the amount aside just incase

im not 100% but i don't think so i think they just upgrade the diff pins. apparently they have not had one problem after doing so.. a bit confused myself.

Does Shepherd do the same things as Jacks Trans?

just fyi for 2011 owners, I sent my diff into shep for the pin and torrington bearing upgrade, and he said the pins were updated to the better ones. So technically 2011 evo pins should be fine.

I still had them do the torrington bearing upgrade since they already had the diff.
Thanks for the fyi

Of course this is speculation, but what I have gathered from this discussion in other threads is Mitsubishi started adding a heat coating like they used to do on the older differentials.

Which makes sense because that is the cheap and easy fix to the lack of lubrication problem.

"If we can't fix the heat problem caused by lack of lube... we will make the part more resistant to heat!"

So for confirmation mitsubishi replace the pins in the 2011 models( with ones that flow better oil) and added a heat coated lubricant? And this is incident is associated with 08-10 years?

Good news 2011 owners. :)


No, the 2011 models have been corrected by the manufacturer. There is no need to replace the differential pins. As far as the Torrington bearing upgrade, you can wait on that until you decide to do the street/strip rebuild.

Thank you,

Trevor
ShepTrans

Ok, try to follow me here. There are some big assumptions required for my hypothesis.

So if we all agree that this issue is cause by a lack of lubrication to the gears while the diff spins. Then couldn't one replace the diff fluid with something that lubricates better and wears less, thereby limiting the friction when the oil is not present?

I replaced my fluids with AMSOIL, and if you believe their advertisements (a little stretch here, I know), it should wear better and lubricate better.

I'm hoping I am better off. I will check the pin whenever my clutch finally goes bad. But until then...

Ok, try to follow me here. There are some big assumptions required for my hypothesis.

So if we all agree that this issue is cause by a lack of lubrication to the gears while the diff spins. Then couldn't one replace the diff fluid with something that lubricates better and wears less, thereby limiting the friction when the oil is not present?

I replaced my fluids with AMSOIL, and if you believe their advertisements (a little stretch here, I know), it should wear better and lubricate better.

I'm hoping I am better off. I will check the pin whenever my clutch finally goes bad. But until then...

Thats exactly what I said, but from what I understood its more of a inside job. As if you literally have to take the tranny case apart and fill the tranny fluid in this one spot where the problem is happening...

also for whoever posted 2011 this problem was fixed i hope so i will be a happy camper :godance:

Good news 2011 owners. :)

No, the 2011 models have been corrected by the manufacturer. There is no need to replace the differential pins. As far as the Torrington bearing upgrade, you can wait on that until you decide to do the street/strip rebuild.

Thank you,

Trevor
ShepTrans



god I wish it wasn't my diff they learned this on... I would have saved at least 500 bucks and a couple weeks of down time...

Aren't the 2010 models upgraded too? Or is it only the 2011?

couldn't one replace the diff fluid with something that lubricates better and wears less, thereby limiting the friction when the oil is not present?

thats a chicken/egg problem. the problem is that the lubricant is not present. Adding a better lubricant will not help when it's not present. So no, changing the fluids won't help since the problem is that the fluid isn't getting where it needs to be in the first place.

I think Stock was running Redline or Amsoil when his went, if that's worth anything.

thats a chicken/egg problem. the problem is that the lubricant is not present. Adding a better lubricant will not help when it's not present. So no, changing the fluids won't help since the problem is that the fluid isn't getting where it needs to be in the first place.

I think Stock was running Redline or Amsoil when his went, if that's worth anything.

Well, oil doesn't just disappear.

And yes, that is worth something. I guess I'll get mine checked out / fixed when I do my clutch.

So why isn't this a class action lawsuit item? Evidently Mitsubishi realized there is a problem and decided to make some kind of solution for it in the later models. To me this is exactly what the GT-R guys dealt with. I further think it should be turned over to NHTSA due to imagine what could happen if the diff lost all fluid while at highway speeds.

Aren't the 2010 models upgraded too? Or is it only the 2011?

When I was sending mine into Shep (mine was the first 2011 they saw), John told me that he hadn't seen a single 2010 unit with the upgrades pins stock

Golden fluid doesnt dissapear! the pins dont get enought fluid..

here a thread that hollywood started not to long ago.

http://www.evoxforums.com/forums/showthread.php?t=48245

you're right, it doesn't disappear. The centripetal force of the gear's rotation expels any oil on the gears away from the center of the gear. The gear pin's are in the center. A higher speeds, the rate of oil ejection is greater than the rate of delivery, so you have a starvation problem. at least thats how i understand it.

hence Jack's solution: add scoops to inject more oil relative to the rotational speed of the diff.

I got Jack's scoop mods on mine during the build. Can't be too careful.

What constitutes high constant speeds? I spent about 3 months highway driving to and from work at about 75 mph

High LOAD, high speed. Driving on the highway isn't a high load.

Sent from my HTC.

so then if your car is under warranty and the pin fails they will replace it with a 2011 diff?

Hopefully

So diff pins will fail no matter what cause of lack oil..?

So diff pins will fail no matter what cause of lack oil..?

Yep yep, only if they fixed them in 2011 like rumor has it

To fix them they'd have to improve lubrication to the pins.

sort of... thats another part of the problem. between the evo 9 and evo 10, mitsu cheaped out and used a different alloy for the pins. the alloy the went with had higher friction between the diff surface, so the pickup was more extreme. using a better alloy means less pickup, mean less rotation, means less wear, even without enough oil. A stronger alloy would also be nice :)

Thats what's been done to the 2011's. It fixes the issue of the pins wearing, but it DOESNT fix the oil starvation issue. Over time, it could transfer the damage to the diff gears themselves, which is more expensive to fix. we'll see over time.

They pins could be forged titanium and they'd still wear/break. I think Jack's has the right idea. Especially since they have tested wear before/after.

your going to have to replace the pins anyway. if you want to go with the same shit OEM ones that are proven to fail, be my guest. seems like a bad place to try to save $40 to me, though

Think you're confusing me with someone else. My trans already has the new pins and fluid mods/built. ;)

lol just sounded like you were suggesting NOT replacing the pins while adding oil scoops

Oh no, definitely replace them! :)

So basically all Evo x from 08~10 diff pins will fail ? Don't matter how much or how little of whp u have? Damn it..

Btw how long is downtime? About estimate cost?

So basically all Evo x from 08~10 diff pins will fail ? Don't matter how much or how little of whp u have? Damn it..

no. There are plenty out there that are working just fine.

Btw how long is downtime? About estimate cost?

Would be wasteful to do it by itself. Better to do it with a clutch swap since the whole tranny needs to come out. I would say ~700 for the clutch job and another 100 or 150 for the diff pin job.

^^^ its 400 bucks from shep and around 1200 for jacks. Jacks does more though I think but im sending mine trans/diff to someone next week.

^^ I'm sorry, I was just quoting the price for replacing the pins (not including cost of pins). If welding is involved, its obviously more time/money. Shep's method goes the furthest....but remember....it hasn't been proven to solve the issue on the X. The solution is based on their years of experience with transmissions on DSMs and Evos from what I know.

Does anybody know if people with aftermarket diff-pins have also seen this issue?

I drove my jam packed x from CA to MA at high speed for certain stretches with only 2k miles on the car. Really hope this doest happen before I can get a replacement ready.

Thanks for info fellas.

^^ I'm sorry, I was just quoting the price for replacing the pins (not including cost of pins). If welding is involved, its obviously more time/money. Shep's method goes the furthest....but remember....it hasn't been proven to solve the issue on the X. The solution is based on their years of experience with transmissions on DSMs and Evos from what I know.

Does anybody know if people with aftermarket diff-pins have also seen this issue?

Lifetime warrantee might help.

"Have the piece of mind that your diff will live forever with our modifications and never give you an issue again! We offer a lifetime warranty against center diff failure due to how well our modification works! Ask any of our competitors if they would give you a lifetime warranty on your center diff, we believe the answer to be 'NO'." - jacks transmissions

Oh yeah, mine broke for the 2nd time after being welded. but it still on warrantee so i'll let them do what they want on it till it breaks again then i'll either go Jacks or shep... Again, loving the lifetime warrantee on jacks.

Still a$$ed out on removal and installation if it ever breaks.

so if mitsubishi knows there was/ is a problem with the diff pins and changed them in the 11 model, can the rest of us not get organozed and send a letter or something to mitsubishi or any governing body to get ours replaced before they fail

so if mitsubishi knows there was/ is a problem with the diff pins and changed them in the 11 model, can the rest of us not get organozed and send a letter or something to mitsubishi or any governing body to get ours replaced before they fail

Would be nice. I want to be a fly on the wall at their meetings.

"Well, we should probably upgrade the pins to take care of this problem"

"In exchange, we'll give them cheaper plastic head covers!"

so if mitsubishi knows there was/ is a problem with the diff pins and changed them in the 11 model, can the rest of us not get organozed and send a letter or something to mitsubishi or any governing body to get ours replaced before they fail

I don't know, one of my first cars was a '98 GSX I bought used and that developed the infamous crank walk. On the DSM forums, it seemed that there wasn't any resolution by the factory, not to mention that getting a right front axle was a nightmare from Checker auto! Got a lot of looks from girls, so that was cool.

"In exchange, we'll give them cheaper plastic head covers!"

I know right! I know they want to save weight but C'mon, thats pretty weak. Just like the plastic CMC.

So if you are driving, what would it feel like if your diff pins backed out? What would the issue be?

Grinding noise in some cases, depending on how far they have backed up.

would your wheels lock up?

You'd sooner gut the trans if they backed out at highway speeds. But I could see it not allowing the car to roll freely once it was stationary.

I ask because this is what happened to me today.

The other day I was driving and threw a ACD U0431. Dont know what that code is as I have yet to look it up. Then today, I was going about 5mph and heard a decently loud grinding sound, almost like my exhaust was dragging on the ground, and then my car didnt want to roll forward any more. Couldnt push it or anything and had to get towed to get it back home

ouch!

Double ouch

I ask because this is what happened to me today.

The other day I was driving and threw a ACD U0431. Dont know what that code is as I have yet to look it up. Then today, I was going about 5mph and heard a decently loud grinding sound, almost like my exhaust was dragging on the ground, and then my car didnt want to roll forward any more. Couldnt push it or anything and had to get towed to get it back home

That sounds symptomatic of the pins, unfortunately. Hopefully not.

Every 5 speed owner should correct this issue whenever they do a clutch. Hopefully they last that long.