mintswack

So gave the shop a call, told him that I'm still having this problem.

His suggestion is to bring it in the shop, have it checked out and if it's definitely something with differential he'll have to make a call from where he got the differential regarding the warranty.

I also sent him an email with the videos and mentioned that differential could still make noise while straight. I'll give a call back later today to see what he has to say about the videos. I'm just hoping this doesn't turn into a nightmare where he's trying to screw me over! We'll see though! Thanks for the info!

Alex3000

A little late to reply but I am just giving a +1 on pinion bearing. BUT with a little added diagnosis

Never happened on my s2000 but I also race an rx7 and have had to replace pinion bearings twice on my diff. I know someone asked if just the differential (ie. 3rd member) was replaced or if it was the entire unit. This is an important distinction because obviously one only replaces the unit in the center and doesn't address the pinion.

OK here is my thoughts on this issue:

The question is why would you be eating pinion bearings? If indeed the whole unit was replaced (as you said it was) then what has happened is you have gone through 2 sets of pinion bearings.

What is going to causes the most stress on the pinion is a change in angle of the differential with respect to the drive shaft. In a solid rear axle car pinion angle changes as the car rolls and moves up and down. People do a lot of geometry work to minimize this angle for track set up as you can eat diffs pretty quickly if you have it wrong (ask me how I know)

But an s2000 is an independent rear setup? The differential should never move with respect to the axle? This is why I beleive your issue may stem from bad differential mounts. This would cause lateral pressure on the pinion bearings while accelerating, braking, or turning. This heats up the bearings and obviously destroys them. The heat is why your diff oil exploded out the breather.

My GUESS is during hard track use your marginal differential mounts finally gave up, allowing enough movement during hard braking/cornering to cause the pinion bearing to heat up and destroy themselves.

This would explain why you could have put a new(used) diff in and the problem came back. Because the mounts would still be bad. I am not sure how much the mounts cost but you may want to replace them when they put the new diff in (assuming they do). I am not sure if they are bad or going bad it would easy to tell? I haven't actually taken an s2000 diff out before

Please keep us posted!

***If I can just defend your mechanic a bit I can tell you from experience diagnosing differential issues is not easy. They are very finicky.

Gregg Lee

I would add to consider that if you only lift two wheels, then the bottom of the car is not level, so it will be more difficult to find a secure location for the jack stands. If the bottom of the car is not level, then it may make contact only at the edge of the stand, off center, and predisposed to slide, compared to centered across the whole width of the stand.

jkelley

I would add to consider that if you only lift two wheels, then the bottom of the car is not level, so it will be more difficult to find a secure location for the jack stands. If the bottom of the car is not level, then it may make contact only at the edge of the stand, off center, and predisposed to slide, compared to centered across the whole width of the stand.
[/quote]
I'm sorry. You're right. When I jack up one end of the car I also have my hydraulic jack preloaded to the bottom of the diff.

SpitfireS

Remove the rear wheels if you're going under the car, engine on, in gear.
Much less rotating mass, much safer.

mintswack

**UPDATE**

Again, thank you all for your input! Currently I'm still in the process of getting the car fixed, so I'll give you guys the update of where I'm at as of now.

I had spoken with to the owner of the shop of where I got my new (used) differential and explained to him all of the noises my car is making. Sent him an email of all the links and a more descriptive explanation of the noise. He told me he was going to call the place where he got the differential to let them know.

Before I decide to bring it back to him, I wanted to get a second opinion on the noise... so I took it to a shop that was recommended to me from the s2ki locals, Young's Auto Repair. He's seen his share of s2000's and also owns his own, so this guy knows what he's talking about. What they found was that the noise was all 100% differential. No noise coming from the transmission, the wheel bearing, nor the brakes. He said that this is a common noise that he sees in failing differentials and that it could be scarring involved and that the only way he could prove it is to open it up, but he did not want to touch it as I told him I have a warranty. He recommended I bring it back to where I got the work done and inquire about the warranty.

Now the difficult part...

So about 5 days go by and I still havent heard from the shop where I got differential, so I called them to ask about the status of the warranty and explained to him everything I had found. The reason why he didn't get back to me because he's been fighting with place regarding the warranty because...

1. Their warranty does not cover that SPECIFIC noise coming from the differential
2. The only noises they cover are whining noise on acceleration and deceleration

He instructed me to drop off my car on Sunday to take a look at it. After I got off the phone, I thought to myself, wait a minute... I should call this junkyard shop because how can I not be covered?! This is a faulty differential! So I call the shop back to get the number to this junkyard, the owner gets on the phone and in a very annoyed and flustered tone says "Just drop off the car on Monday! Okay?!" Unfortunately I was at work and couldn't really get into argument about this. Something is just really odd about this. Unfortunately my plan is to just drop the car off, let him have a look at it so he has all his facts and see what he can say to the junkyard shop to fullfill my warranty.

So as of now I put money into a broken differential and not sure if this junkyard is going to give me my money back. I was also informed to get my old differential back so I can have the option to sell and rebuild it but don't know what's going on with this junkyard. Sorry for the long post but a lot has happened this past week.

If anyone has any thoughts or opinions regarding this situation of mine, feel free to chime in. Thanks again!

Gregg Lee

What a surprise!

Stop and think about this. His first story was not believable and was a stall. Why believe this new one about the junkyard warranty, which is even less believable.

Perhaps without intending to do so you have called his bluff, but without directly accusing him of lying. That's why his annoyed. He may think you just outsmarted him. Now he has to think up a new story. Forget the apocryphal junkyard. Your warranty is with him. The junkyard his problem.

Originally I said check your state's consumer protection laws on auto work. They are often stronger than general consumer protection. That still applies. Hopefully with that as leverage, I would press the shop for a cash refund. Then negotiate to either: let them take out the diff, put the old one back in and tow the car to shop of your choice. Or Get your old diff back in a box, go to new shop to have the diff replaced or your original repaired, then return the salvage diff to them. Do not agree to deferring any of the refund until after you do the repair. This is no longer a "core charge" situation. This is caught red-handed.

Don't let him claim 30 day limit. That ended when you complained.

JL140

Is there any possibility that a bad bearing (or multiple) on the secondary output shaft can produce a similar sound?

Mine has been making a sound similar to this audible when off the throttle at ~30-60km/hr (but not as loud) since purchase 2000km/2 months ago. It's an '01 with ~114.5kkm on the clock.

mintswack

**9/15 Update**

So I looked into consumer laws regarding issues that haven't been resolved after first time repairs. You apparently have to give them the opportunity to resolve the issues before you get any type of court involved. So the car is back at his shop and says his biggest issue is trying to track down another AP2 diff. His plan is to track down a pinion bearing replacement as he thinks that could be the culprit and that will be covered by the warranty. He told me if that does not work, he could consider refunding for the replacement differential, but not the labor... The whole differential is not covered under the warranty bc like I said, that specific noise is not covered and they will not cover a rebuild that I can get from s2kpuppydad.

I want to get this shop's contact information because 1.) they have my old diff, & 2.) a part of me actually thinks that the differential was not replaced, and that I had paid for a really expensive diff oil change. Is there anyway to prove that the differential was replaced or not? This owner/mechanic is refusing to give me the number of the salvage yard, saying that the last people they want to deal with is me, and that they will only deal with the his shop. It just leaves me being skeptical...

I'm planning to show up unexpectedly this week and demand contact information from the salvage yard, so in that way he has no way to hide or time to stall.

Thoughts?

Gregg Lee

Don't believe a word he says. He has no intention of doing anything.

You have already given him a chance.

"Plan is to track down" a bearing? What does that mean, a used bearing? You can't reuse bearings. You just pick up the phone and order one. Don't believe a word he says.

Be sure that he can't hold the car for ransom. e.g he does more work, wants more money, refuses to release car until he gets it.

Small claims court. Varies by state, but typically judge only, upper limit on claims, participants must represent themselves (no lawyers in the court room), minimal court cost. Perhaps a useful lever to get a settlement, rather than actually doing it. Likely a waiting line for a date.

Did he change the diff? They sound was different before and after, so seems likely. And you have driven the car, so nothing is definite, but I suppose you could look at the prop shaft and axle flange bolts to see if they look like they have been removed. That is, if there is an dried dirt, oil, and rust layer bridging from the edges of the bolt heads to the shaft flanges, especially on the prop shaft, probably has not been disconnected. If bolts were taken off and on they should have been cleaned and lubricated before reinstalling. Also the original prop shaft bolts are notorious for becoming stuck over time from dirt, oil, baked by exhaust heat. A newly installed set should loosen easily. The torque spec is only 24 ft-lb. Unfortunately he has the car and you don't.

But in the interest of time and trouble, you may want to just negotiate the best cash refund you can and go somewhere else. Swapping a differential shouldn't take more than a couple hours at a shop, on a lift. That's not much labor. He wants the problem to go away, so maybe just get what you can and learn for next time.

But, as you negotiate, where is your old differential? You paid for the replacement, so unless the old one was specifically part of the deal, you still own the old one. If it's now gone, then ask him to pay for it.