cmnsnse

I've made it across the country a few times, MD-Az, MD-OH, and those were the most frequent. (All in the S2000)
Im a driver, I think nothing much of getting in an driving for 10 hours, 18 being the longest I ever did (1400 miles)straight. I also enjoy hitting the back roads, and powering out of turns . . . another situation that could add to whole picture. (just like the shakes - takes some time to build up, and some may never have a problem)

The whole point of the high speed is the volume of oil being pumped, resulting in a low level by the pickup.
I believe that only time will tell about the longevity of these transmissions. I also believe if people start driving through the mountains at 100+ we'll see more failures pop up.

I didnt think too much about the foreign transmission failures 2 years ago, and figured hey if my car made it to 38,000 miles it must be OK . . . Just dont say I didnt warn you

cdelena

If it was that rare a case they would not have replaced transmissions in Europe.. and Luis, a board member would not have been stranded in similar fashion after a long high speed run. I believe this is a simple design shortcoming that may or may not have been fixed in later production, where AHM did the analysis and decided it was cheaper to deal with a few failures on warranty than open a lot of transmissions. We simply have relatively flat roads and slow speeds keeping us from too many of these failures.. so far..

MarkS2K

Sure, we in the US won't go at sustained high speed (100+mph), but I worry about the long term effects of the pump being inadequate at even 50 mph. What's going to happen when we hit 100,000 miles. I have no doubt that the engine will easily last that long, but the tranny might not.

Tanqueray

So, just to clarify:

Driving straight at 100mph is ok for hours at a time
Driving straight at 100mph on hills is ok for hours at a time
Driving left hand curves at >50mph will cause momentary loss of lubrication
Driving curves for hours at >50mph may damage the tranny
Driving for hours at 100mph with occasional curves may damage the tranny

Is this accurate?
Tanq

cmnsnse

I took it to 125, with no problems on a straight and level road - a steady 4 psi.
The slightest bend to the left at 80MPH and the gauge dropped to ZERO psi.
I observed a loss of pressure (Zero) even as low as 50 mph (moderate cornering to the left)

At this point all I can do is speculate what amount and type of driving will lead to damage.
I can guarantee that when you take a left hand turn at a moderate speed, you have lost pressure in your transmission oil system. The question is how long, and under what loads can the tranny survive?

I believe my transmission did not fail just because of that one day of driving, but because of the 38,000 miles logged before that trip. I can remember going to Ohio, on I-70 west with down hill sweeping left turns at 90 mph - thinking back, hey there was no oil pressure at that time. . . oops

As the speed of the vehicle increases the fluid level drop can be described as a curve, the initial amount of drop is the volume it takes to fill the countershaft/mainshaft/output shaft, and galleys. (Ill eventually get the volume numbers, be patient) The second part of the equation is how long it takes x amount of oil to make its way back to the bottom of the tranny at various RPM and volume being pumped. There is also a relief valve just above the pump rotors that lets over pressure exit into the rear cover, needing more time to get to the front again. Then add G-loads, and attitude. That's when the deficiency begins. Like I said earlier, now its a matter of what can be sustained without pressure.

Lower speeds need harder corners to suck air, downhill(wish I had some hills around here) will do the same thing. The pickup is to the drivers side and towards the rear of the tranny.

Most peoples first impression of the oil system in the S2000's tranny is: "Hey its an added benefit . . ."
Well, I believe its an integral part of the design - anyone want to try running without the pump working?

If you all knew how little I had to turn the wheel at 80mph to get the gauge to drop to zero, you would not have bought the car.

Again, this tranny being tested is a vin #6xxx (I'm sorry I don't want to crawl under there right now) of the year '00
I could safely guess every earlier vin has the same problem, and we don't even know if they decided to implement a fix on US bound cars.

MarkS2K

So cmnsnse,

Maybe we should provide all the data to Woodwork and see what he has to say about it.

cmnsnse

[QUOTE]Originally posted by jzr
[B] Made the trip back a few days later in about the same time, again no problems.

Yet to me this isn't half as hard as a day at the track, with all the heat and full-throttle upshifts.

cmnsnse

Im waiting to hear from him, I have a hard time believing he doesnt know. Say's he's waiting on info from Europe . . .

StormBringer

common sense.

There might be another explanation. I had my transmission fail due to inproper tolerances on the shifting forks and collets. It lead to a huge increase in temperature in the tranny as wel as the failure of 5 (2-6) syncro's. Why it does not explain the fluid psi strangness it might explain the failure of your box over that of people like JZR who whould have been more suspeptible to this problem.

cmnsnse

[QUOTE]Originally posted by StormBringer
[B]common sense.