I agree that the flex discs should be checked every chance you get, but what most here are ignoring is the fact that a bad flex disc talks to you more thu vibration than sound. It's obvious that your noise is coming from somewhere forward of the rear of the transmission. It could be flex plate or something as simple as something rattling against an exhaust pipe, or even a broken weld.

We actually dragged it out for a week. Including one day we spent 3 hours of cleaning the grime from the transmission, transmission tunnel and back of the motor. But I would say actual repair at a slow pace can be done in a full day. But probably a good weekend should be sufficient.

Front pump seal is like 5 bucks, few bucks for crush washers, and the expense of transmission fluid and filter change.

Another tip is you need to look out for the torque converter being damaged on the flex plate mounting surfaces where the bolts go in. If the flex plate is damaged enough it can rub and wear the mounting surfaces. If the flat mounting surface has been reduced in size it can cause alignment issues and strength issues. So be on a look out on that.


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I was driving it around today and tried to pinpoint the sound some more. From beside the car it sounds like it is coming from the torque converter area. However inside the car it almost sounds like its coming from the fuel tank :confused: I was thinking maybe it has to do with the lift pump surging fuel back into the tank? I don't think it is exhaust, when I was under there today it looked ok, was pretty solid. Also, I would imagine that the turbo would muffle the sound of each cylinder a bit--this sounds almost like nailing on one. This is driving me crazy!!:dizzy2::freak::bomb:

Edit: I still haven't had the time to crawl under the car and check the flex plate, I have to clean the whole thing first, there is years of gunk on the bellhousing...seems like a weekend job.

FTW

I should add I recently checked the flex DISCs for any wear when I was servicing the transmission, and found no play in the driveshaft. My differential does have a whine however, only noticeable without the seats or rear deck in so its not too loud. A diff oil change is definitely in the short term plans. I recently changed the wheel bearings while doing the brakes, inspected everything back there. The subframe mounts are like pancakes so they need to be replaced, and the swaybar links are loose/need to be replaced. Halfshafts look okay, and the boots are still in good shape.
However I don't understand how these items would really carry a knock that is 100% correlated to engine RPMs. I do see what you are saying with vibration, but this is constant even when the engine smooths out from idle. Thank you all for the suggestions. --TC

Car is in N and making these noises when revving?

I have the same problem, I think, and I believe it to be the flex plate. I bought one on this site. Seems like an awfully small triangle and I'm worried it is not the right part. Anyway, I'm taking it back to an independent transmission shop and they are going to change it out. Anybody ever paid somebody to do this job? How much did they charge? Thanks

My transmission guy typically charges $85 an hour. R&R no including bench time averages $650 (can $ of course)

update: The noise has something to do with the fuel return line surging into the tank. I was under the car today and checked the flex plate. It looked okay to me, though there wasn't too much room to see. I ended up replacing all of my fuel lines in the "going crazy" process as a preventative measure (and maybe trying to get the power back in the engine?). I also threw some sea foam in diesel-purge style from a can and the noise stopped. However, I noticed the return line was putt-putting pretty bad, though I think the cigar hose is designed as sort of a muffler for this. I was happy to realize the noise stopped, but now I wonder if this is normal for the lift pump to be so violently pumping that it creates an audible noise in the tank?

FWIW the fuel is clear finally (after draining the tank, I have another thread on this) and replacing every little bit of fuel hose under the hood seems to have sealed things up and restored some power. I'll admit I freaked out a bit on the flex plates :(