Last night on my way home from work, i was driving on the freeway, and i see a berlina my05 top down behind me, he then pulls up next to me and tells me that there's something leaking from my rear. i was only few exits away so i drive home, and i look under the car, and it was all oiled up, even my rear bumper. its the rear differential leaking. ive never had this problem before and as i can recall i Didn't hit anything on the freeway, as anyone else had this problem? how serious is this? and how much should i be looking to spend to get it fixed? im about to take it to a shop, but i still wanted your guys opinion. thanks in advance.

 

it is serious. you are losing oil in diff... I think you should not drive at all since driving will damage it further. It may cost more to fix. if it's just seal that was broken, it could start from $300~$400. if it needs replacing other parts such as flange, gear, lsd, or so, it will be more than $1,500. if you want to stay stock, it might be better of buying used pumpkin in good condition off e-bay for $500. But if I were you, I will take this opportunity to upgrade to comptech housing and gear.

 

Find out where it's leaking from first. THEN, you can have the brain aneurism.
If it's because you left off the drain bolt washer, that's an easy fix. It just gets worse from here.

 

find out where its leaking. its either going to leak from the drain bolt, the seal between the front and rear housings, or from the pinion gear oil seal.

my money is on the pinion gear oil seal, though.

 

k so after taking it to the shop, they tell me its the differential, didnt say exactly what part is leaking, but they said they'll charge $450 to take it apart to find out what the problem is and if its the gear that it would cost around $3500 in that case. so i didnt feel comfortable paying 450 to just look at it, i ended up driving the car home, and tommorrow im getting another quote from a different shop. the car only has 26K miles on it but its not under warrenty since its 2001 model and the year has expired. what i dont understand is how it'could have happened.??? the engine is stock and its only lowererd 1''. btw im

 

Hey there. That was quirky 'ol me in the santa hat with the black S2000 that night. Yea man, I noticed somethen was leaking all over on your Y-bend on your exhuast and rear sway bar. I figured it was a rear diff leak becuase theres not much else back there to leak.

Don't know if you have your local shop you go to, but a bunch of us S2000 guys go to B&J's Auto down here in Campbell. It's a bit farther south for you i believe, but they do awsome work, and might give you a better price too. That leak looked rather large to be something small. I haven't heard of any strange rear diff leaks before, something might have jammed into it in the past and jarred something the wrong way.

On an off note, there's a handfull of us who always go hang out together, we're good freinds and get together a few times every week. You're more than welcome to come on out. I liked what you did with your S, simple and clean. What wheels were those?

 

Just a WAG, but did you confirm that it wasn't the differential mount that was leaking? These are fluid filled and make a mess when they leak.

 

so the mechanic tells me that there've been a TSB about the CV Joint making rear vibration during acceleration, which was the same thing my car was doing for about 2 weeks before i had the leak. so he tells me that it'd had damaged the bearing in the differential. so i went to the honda dealer and showed them the TSB but they tell me that, since its no longer under warrenty (25K miles but 2001model) they can't fix it, and he went on explaining, that its not a recall so they dont fix it unless it's under warranty.
is there any thing else i can do? or do i just have to take their word for it? or am i going to have to get it fixed on my own and not even bother with the dealership? any info. will be helpful. thanks

 

a damaged bearing will squeal/grind, etc. a seal failure will cause a leak. as said already, its either the drain bolt, the pinion gear oil seal, one of the axle flange seals, or the differential mount leaking.

get under the car and see where its leaking and then we'll tell you what to do.

 

i had a leak once too. just go under clean everything then add more fluid if there none left and look for the leak. mine leaked from the output shaft seal. it was a cheap fix but i replaced it myself