Possible transmission noise...

[ChilinMichael]

Few days ago after a full tuneup I took the car out and when I got it back home, I hear a whirring noise. I stuck my head around the engine bay near the pulleys (where it seemed to come from) and decided that the belt tensioner pulley was going south as it had in the past. Brought it into the shop today and sure enough after taking the belt off, there was play in it. We changed it out, things seemed fine. Now mind you, this noise only occurs after the car has warmed up, infact, I could shut it off for a minute, turn it back on and it's good. Got home just now and heard noise again, wondering what the hell is going on. Stuck my head around engine bay again, this time both sides. Realized it's coming from both sides of the engine bay and certainly sounds like the transmission. Sometimes even if I get it home at idle it's noiseless, but if i rev it...noise occurs. Thinking fluid drop and filter change. Any other thoughts? Fluid seems good, doesn't smell burnt.

Here's the video -
Started the car, no noise, had to rev to get it to happen. Moved around engine bay to show noise level.

http://www.youtube.com/watch?v=MIpIRQXWPfw

[crash93ssei]

Have you ran it without the belt yet to confirm that the noise is not in the accessory drive somewhere?

[ChilinMichael]

I guess I'll try that, but I'm pretty convinced it's the transmission, as you can tell in the video, the volume of the noise is equal and if I stick my head down on the driver side, def. sounds like coming from the transmission casing.

[ChilinMichael]

Did transmission service today. Found the other half of the thrust washer piece we found at 170k. Filter and fluid. Overdrive is nowhere to be found, and torque converter, even if it does lock at 42, disengages at 50 and that's that. 3,000rpm around 65mph-ish. Guess she needs a rebuild...

[PRD2BDF]

4T65E 4EVER!

But on a serious note, I'm sorry to hear that. Hopefully the rebuild won't be too costly.

[ChilinMichael]

It made 200k, and I beat the living piss out of it most of the time. It's been run down a quart of fluid in the past for quite a while (unknowingly), etc. Once we did the fluid drop and filter change, it came out with no O/D and the torque converter doesn't wanna do it's thing. Rebuild is in the ballpark of $1,500. Unfortunately I really don't have a job, I had part time at my friends beer distributor for a few hours a week, but that's too far to get to now with the car the way it is. I'm filling out endless apps in this awesome job market trying to get something very local.

[SSEiMan01]

Sucks to hear Mike!

I know all too well about receiving bad transmission news.

[ChilinMichael]

I WIN!

Thanks to Don (JRS3800) for the advice. Disconnected battery for 30 minutes, turned the vacuum modulator up a half turn to raise line pressure, and took her for a spin after. TCC lockup happens a slight bit earlier on, and overdrive engages quicker than it did in the past for sure. I'm pretty sure this is a temporary fix as the trans still makes some oddball noises, but at least I have TCC and O/D for now. (I attribute the noises to the now entirely missing thrust washer from who knows where)

[renchjeep]

Checked out your YouTube video, and it sounds sadly and expensively like my 94 SE just before she shredded the "coffee-can", or reverse reaction shell at 187k or so. I got about 1000 miles after this noise started, then it grenaded. $2200.00 rebuild, and all is well....almost! About 20k after the rebuild, I started losing lockup, then 4th gear after about 15 miles on days above 70 degrees. Now it appears that I should have insisted upon the Sonnax TCC apply valve upgrade. All other "upgrades" were supposedly done, including a "hardened" reverse reaction shell. I installed a "big" stacked-plate tranny cooler (which helped for a while), and an adjustable modulator, and I am now curious as to which way you turned the adjustment screw to "help" your problem. Maybe I don't need to pay my trans guy another $500.00 to do the Sonnax TCC upgrade just yet?

Almost forgot the thrust washer part...I did find half of that (same?) gray plastic piece upon my first drop of the pan immediately after I got the car...it was just laying there, in the pan, saying to me "YES, I am about to cost you money!"!!!

[ChilinMichael]

Clockwise, a full turn. I did a half turn, took a long drive and it went into failsafe again after sitting in stop and go traffic getting hot. At buddies, went the other half turn, drove home 45 minutes with overdrive. Now she engages O/D at 48mph and TCC Lock at 38mph. Earlier than before...

[bad.moshi]

I've been having strange problems with my lockup as well lately...wonder if that could help. Seems to want to cancel/disable o/d all together when the tranny gets warm... Driving up mountains, I have to disable it or I risk not having o/d when I top the mountain or up until I restart the engine... Seemed electrical to me, but it only happens on long or mountainous drives..

[renchjeep]

Well, adjusting my modulator did not help. My trans guy (the guy who rebuilt my trans less than 40k ago) says it could be a warped valve body, or a bad TCC apply valve/solenoid. But if it was TCC related, I would think I would lose only lockup, not 4th gear shortly after. Turning the ignition off while rolling at speed in nuetral, and re-starting seems to fix it for a bit.....but I always lose lockup, then 4th gear again. This is getting annoying.......as the weather gets hotter, this problem gets worse. She was good for the winter, now acting up again.

Any trans experts out there have anything I can go on? Where would you start?

[Jrs3800]

Rench you should be setting slip codes....

Most likely the PCM is commanding TCC lock and the Slip RPM's are not dropping in the manner that they should, when this happens the PCM defaults to 3rd gear and no TCC lock... Restart and you will get TCC lock and Overdrive until you have the slip issues pop up again..

[renchjeep]

Rench you should be setting slip codes....

Most likely the PCM is commanding TCC lock and the Slip RPM's are not dropping in the manner that they should, when this happens the PCM defaults to 3rd gear and no TCC lock... Restart and you will get TCC lock and Overdrive until you have the slip issues pop up again..

No Check Engine light, but this is OBD 1.5....gotta scan her. Just to clarify, I don't lose lockup and 4th all at once.....I lose lockup, then 4th, maybe 30 seconds later, maybe 2 minutes later. Depends. Upon what, I don't know.....

I have verified the loss of lockup by stepping on the brake pedal, and the rpm's do not change. That tells me that she is in 4th, no lockup. Shortly after that, I lose 4th, and she drops to 3rd gear.

I have a 180 drilled stat installed now, and have on-hand a 195 Stant Superstat. I was thinking of going back to the stock temp stat, and supplying an additional trans ground. I already installed a "big" stacked-plate trans cooler, bypassed the radiator cooler, and that seemed to help for a while....

A bit of history.....when the car was given to me, she had trans problems, and the charging system was not working well. I serviced the trans, and bought a "good" used PCM off eBay. The PCM fixed the charging system, and seemed to help the trans as well. Then the coffee can grenaded. $2000.00 rebuild, with "upgrades" like a hardened coffee can, Corvette servos, shift kit, etc.

Trans guy said valve body checked out "ok", so he reused it. Now he tells me it may be warped. Out of warranty, of course. So.......

Am I next in line for another rebuild, or would you go with a new valve body and the Sonnax TCC upgrade? Or would you be more inclined to ground the trans better, install the 195 stat, and look for another "good" used PCM?

[Jrs3800]

You really do need a scan... You need to know if everything is functioning within its range... TPS would be on the top of the list.. This can cause issues with the TC Lock and Overdrive... Just as well Slip Rpms in TCC lock will also trip codes( will not set the SES light ).... If you have any codes those would be good to know.. Would also be good to monitor the TCC Slip Rpms when the TCC is commanded on and the PWM is 90-100%...

[renchjeep]

You really do need a scan... You need to know if everything is functioning within its range... TPS would be on the top of the list.. This can cause issues with the TC Lock and Overdrive... Just as well Slip Rpms in TCC lock will also trip codes( will not set the SES light ).... If you have any codes those would be good to know.. Would also be good to monitor the TCC Slip Rpms when the TCC is commanded on and the PWM is 90-100%...

Oddly enough, I have replaced the TPS several times, the latest one being a new Delphi unit. My "cheap" $300.00 scan tool can't do all the stuff the several-thousand dollar ones can....guess it's time to pay a "real" shop to diagnose this one.

And I thought I was a mechanic....

[bad.moshi]

Gross, yeah this is the same problem I'm having with my 1993. I'm not getting any codes thrown at all, and my TPS is only about a year old. Great...

I feel liek it's gotta be related to the temperature of the tranny, though because it hadn't happened all Winter, but now that hotter weather is about, it is happening on those days more frequently during longer drives.