Iceplant18

This is my first post on this forum so sorry to begin by asking for help rather than offering any. My girl's 2001 S2K is having what looks to be the early signs of bearing failure coming from what we think is her transmission. I wanted to know if you guys could give me some input on this based on some descriptions and/or if any of you have seen this before.

The car has about 50K miles on it and has been strictly following the severe maintenance schedule since day one. Not frequently raced, not modified, no accidents. About 2 weeks ago while cruising with her I noticed a whirring noise in the cabin coming from directly below the stick shift. She told me that she noticed it about a week earlier and that it had been getting a little worse. After about a week of monitoring it and poking around underneath the car looking for any superficial signs of anything the noise began to get louder and sound a little more distinct. The whirring noise changed pitch, increasing with the speed of the vehicle. Varying engine speeds played no role in the pitch of the whirring which leads me to believe that it's coming from the back end of the transmission or later. Drive shaft looks fine and the tranny and diff have fluid. The most similar sound i've ever heard is when my wheel bearing went out on me in my saturn but that sound was distinctly coming from where my wheel was. This sound is coming from directly below the stickshift/centerarm rest. She took it to the local honda service center for a checkup and they of course advised removing the transmission and tearing it apart to investigate. They believe it to be a "bearing sliding out" in the transmission.

So... anybody ever seen/heard of anything like this? It seems kinda lame that a problem like this would come up on one of these transmission after only 50K miles and proper maintenance. Especially from a company with such a good rep for reliability. Any recommendations on anything else I can check without diving into transmission removal? Any input would be greatly appreciated. Thanks in advance!

chris_barry

I would disconnect the propshaft from the differential and turn the rear wheels while listening to the diff with a screwdriverscope. ( Hold a screwdriver handle on your ear, and the blade on the diff. This will check if the diff teeth are starting to shift as this can cause a whine which travels up the propshaft.

I had a similar noise and on investigation found all teeth on the pinion were peeling away.

Ask the service centre to do this test before dropping the box. One of the first things they have to disconnect is the propshaft so it can be done before removing lots of parts. Also worth checking the magnetic drain plug in the gearbox for particles.

Chris.

chris_barry

Oh, you can listen to the diff with the propshaft attached, and also use the screwdriverscope on the rear of the box. The noise will be louder closer to the source.

Chris.

Squeezer

what fluids are she using in her transmission and rear diff? when were they last replaced?

Iceplant18

Cool i'll try that "screwdriverscope" technique. It's the stock fluid in both the tranny and diff. I know the diff fluid has been changed by Honda at the schedualed interval but the tranny fluid is still the original is the manual says to change it at 60K I believe.

Too add to the situation... she's telling me she's experiencing power loss now.

Squeezer

i'd find out what fluid they put in her diff when she had it changed. if they put in VTM-4 and not a 75w90 or 90w GL5 gear oil then that will destroy the diff with time.

Race Miata

Are you sure you can narrow down problem this way with the diff? I would imagine even a healthy rear-end produces some kind of "noise". If the original poster doesn't have a known-healthy diff to compare with, I don't think he would know exactly what noise to look for.

What do you mean by all teeth on the pinion peeling away? AFAIK, the teeth on the pinion (or a gear in general) either catastrophically break or they stay intact. If the teeth are chipped away, it takes very short time for the broken teeth to lodge in between the ring/pinion and catastrophically break the good ones.

I would first check the record to see if Honda put in VTM-4 in the diff. Failing that, I would change out the tranny fluid with good one, since you've already got 50k on the fluid anyways. If that doesn't make any difference, then try narrow down whether it's the diff or the tranny causing the problem.

Iceplant18

Is this a mistake that Honda service centers make often? It would seem pretty crazy for them to put the wrong fluid in there. I'll see if I can dig up the service writeup record and see if they logged the type of fluid.

This sound is pretty loud. loud enough to make it hard to talk in the cabin while driving at freeway speeds. Although it be a little dangerous. I'm thinking of proping up the rear end and getting the wheels spinning in 3rd gear to see if I can hear where this noise is coming from using either the screwdriverscope and/or a vacumm line to listen around.

Worst case scenario... are there any service manual diagrams posted up here or on the net anywhere for tranny/rear end removal/installation? I may end up having to pull it out myself and taking it to a service center for disection.

S2KenC

Yes, this is a mistake that Honda makes quite often since Honda doesn't have a gear lube for our car.

On my old S2000, I had my diff serviced at a Honda Dealership at 15k. On the receipt it states that they put in Honda Dual Pump Fluid (i.e Honda VTM fluid). Hopefully this didn't happen to your friend.

Here's a link to the oil journals. At the top of this thread, theres a mention about the correct diff fluid for our car and the horror stories of Honda dealerships putting in the wrong fluid.

https://www.s2ki.com/forums/index.php?showtopic=195574

slipstream444

I would think about taking a sample of oil from the diff, just in case the dealer put the wrong stuff in (with or without documenting it properly).
You can buy oil sample kits from a number of sources. You can still have the dealer change the diff fluid out, but I'd stand by with the service manager and ensure a proper sample is taken. Let your service manager know your concerns and you may want to bring Honda of America in the picture immediately if you think the dealer improperly serviced your car.
I agree this sound is more likely a diff problem, and not the transmission. The sound is easily transmitted through the driveshaft.

However, if you find the problem is the transmission ... PM me. I have an '03 transmission with around 15,000 miles on it that would likely be cheaper than rebuilding the transmission.