The fault here isn't in your tune. I would continue to raise hell

 

Yea I would do this as well.

 

While they had the car, they attempted to fix it. They used a junk-yard or otherwise NOT NEW diff replacement. Obviously it was either in the elements for some time, or it was from a donor car that was a flood car.
And when it didn't solve it, they focused on voiding the warranty and distanced themselves from touching the car ever again.

When no other explanation fits, it must be considered as truth.

~Jaraxle

 

So I should get my car put back together by the end of the week. I'm arming myself with all the evidence I can find that this cannot be caused by any mods I made. Aside from finding the defects and having the rusted bearings shipped back to me, i'm having my tech do a complete inspection of every possible line leading to and from the rear diff to identify what the hell happened. I guess likely one of two conclusion will be reached..

1. There was some hose that was loose and water got in the rear diff
2. The bearing that went into my car were contaminated and rusted over time

If it turns out to be item one, I'll eat the cost myself since it will be an uphill battle to claim the lines damaged itself. If item two, I will not let them sit there and dodge the warranty claim when clear fact states no possible build in any configuration would result in rust on two very specific bearing in the rear differential.

 

According to my Mitsubishi dealer, the burden of proof is on them. That is, they have to prove you caused it rather than you proving you didn't. Otherwise they would claim they would attribute every claim to any mod you have. "Well your turbo failed because your WB02 oxygen sensor is increasing back pressure".

If it were me, I would give them one chance to make things right and then I'd file in small claims. It sucks having to sue, but I haven't found arguing with the reps to be super effective.

 

that sucks OP. i agree. keep fighting the fight. gonna have to push the system around a little but as others said..power doesn't cause rust.
Goodluck

 

Appreciate the advice everyone. So after hearing some of the stuff on the forum I called the customer service again and was able to get a claim submitted. This was the first time a customer service rep even presented an option for me other than "go away, your warranty is voided". They told me someone will get back to me tomorrow to discuss further. At least it's moving somewhere.....

 

Awesome to hear. I hope something works out for ya

 

Update: Got a call from some lady incharge of the claim. Started right off the bat saying mod = voiding warranty but I wasn't having any of that today. I told them that they breached their contract as a seller by selling me a $41K car with rust in the rear differential so don't lecture me on car modding and warranty laws. She did say the I will be getting another call from the district manager to explain things further and to review my case to come up with a decision but she said and i quote "I wish you have came up to us before you decided to open the rear differential to do the work yourself because now we are not sure what actually happened when someone else worked on the car". I really lost it there and some f bombs might have gone out. I have called and tried to work with Mitsubishi to resolve this but the dealer and reps all said my warranty is voided and they won't beable to help me to honor the claim when my mods caused w/e it is to happen to the rear diff. Only after alot of time and $$$ did i get the evidence to show them there is RUST in the rear diff of a new EVO FE. I'll keep updating you guys on this so there is a road map in case others run into defects and the dealer/corporate tries to deny your warranty base on this tune bogus claim.

 

You could also stress the point that you took it to the dealer for help BEFORE the warranty was voided. Based on your mileage and the amount of rust, the moisture could have been there from the factory.

 

Stand your ground I like where this is headed, by altering your PCM keep in mind that it just provides electrical signals has no way of affecting a MECHANICAL part..

Somebody did not follow protocol for shipping to the USA, and I honestly will say that your probably not the only with this issue.

It takes 2 to 3 weeks by sea to get these cars here, and salt water loves steel, iron, etc.
They didn't prep the car properly for shipment (anti-corrosives)
Just a guess, keep us informed, hang in there.
And remember the diff is a MECHANICAL part, MAKE THEM PROVE THAT YOUR TUNE caused the diff to rust (lol)

 

Unless it was a SMART DIFF, it disintegrates once it senses MORE POWER

 

Has Mitsubishi always been difficult or have they been more aggressively denying warranty on an orphaned car?

I can somewhat appreciate their stance because of the demographic, but at least keep it within the realm of the possible.

 

That's a good point. Would you happen to know how these differential makes it's way into the cars. Like are they assembled by some 3rd party vendor and sold to Mitsu as complete units? I find it really strange that no one has experienced this before, even on aged EVOs.

 

My dealer said protocol for EVOs and Ralliarts warranty claims have always been more strict due to the demographic of buyers and their intended use. He even said that warranties claims have been denied due to photographic evidence of car having been used on drag strips. So their aggressive stance on warranty claims is not so much that they discontinued the car but people abused the crap out of the EVOs and expect factory warranty for repairs. In the sense, I think they have every right to do so but it would be uneithical on their part of start using this as a weapon against anyone who modded their car.

Another customer had an evo x FE (Tuned by AMS) AYC pump fail. Warranty was denied due to tune. That customer also had to fight through corporate to eventually get them to back down and fix the issue because no correlation can be made between the tune and the failed part. But come'on, why do we as original customers have to deal with this is beyond me....