Looking for some help diagnosing a noise on my ‘04 LJ, automatic. It’s the same whining noise you can hear in this video. From my research, seems like it might be the trans fluid pump. I had a transmission shop look at it, and it has the proper fluid, pressures, and fluid levels. After having to walk the transmission shop through some basic stuff, I’ve lost confidence in them so I’m looking to fix this myself. Any help or confirmation on what it might be would be awesome. Thanks.
Help Diagnosing Transmission Noise
- Thread starter kingofenglund
- Start date
The noise definitely coming from the trans / bellhousing area. The trans shop that looked at it did disconnect the torque converter from the flex plate and the noise stopped. And the noise happens regardless of what gear its in or if the jeep is moving or not
The trans shop basically low-key pulled the trans & TC, noise went away, and they didn't think it was trans related? I mean, did they somehow rule out flex plate or torque converter? Either they are the most honest shop in the world for not trying to sell you a new TC, or they're incompetent. Jeep makes noise, disconnect transmission noise goes away....this is pretty much why transmission shops exist.
Incompetent is what I’m leaning towards. They had completely ruled out the trans as an having an issue because they had disconnected the torque converter from the flex plate and were hearing other noises from the accessory belt pulleys. And even after showing them the noise I was hearing in the video I shared above and pointing out that it no longer made those noises with the trans not spinning they still weren’t convinced it could be anything like the fluid pump. I had to walk them through the noise stopping when the trans was no longer spinning kinda made sense that it was something in the trans. At that point I was told “we’ll we don’t want to just through parts at it and hope it fixes it, so we suggest doing a complete rebuild for about $3,000.”
Hence why I decided they to figure it out myself. With the help of the gurus on here of course.
“Needs a rebuild, $x,000” is pretty much standard operating procedure. From where they had it, I’d love to have inspected the flex plate & put in a new TC. ¯\_(ツ)_/¯
They said the torque was fine (sorry, should have mentioned that already).
My hope is others who might have had the same noise chime in with what they did to fix it.
If your torque converter is fine, and the noise happens only when the torque converter is connected to the to the flex plate and it is regardless of whether the vehicle is moving or not, then it seems like:
- something that rotates with input transmission shaft is making noise. If you are in PARK, AFAIK, only the shaft and the oil pump would spin. In 42RLE the oil pump is spinning regardless of the PARK, as it is connected to the input shaft. If the noise happens when you are in DRIVE, but sit on brakes, the then no planetary is supposed to spin, only the oil pump is supposed to continue spinning.
So, it could be that your oil pump went bad. You can replace the oil pump, it is in the bell housing. Not too complicated. I would do this job myself, if would have enough time for this.
Remove the transmission, remove the torque converter, replace the oil pump, reinstall the torque converter and then install the entire thing back into the rig. If you are at it, and pull the transmission out, then replace the oil filter, valve body and the solenoid pack as well, and add oil pan temp sensor for sake of long term reliability. Also, it might be a good idea to drop a new torque converter, if you can find good and cheap one.
- something that rotates with input transmission shaft is making noise. If you are in PARK, AFAIK, only the shaft and the oil pump would spin. In 42RLE the oil pump is spinning regardless of the PARK, as it is connected to the input shaft. If the noise happens when you are in DRIVE, but sit on brakes, the then no planetary is supposed to spin, only the oil pump is supposed to continue spinning.
So, it could be that your oil pump went bad. You can replace the oil pump, it is in the bell housing. Not too complicated. I would do this job myself, if would have enough time for this.
Remove the transmission, remove the torque converter, replace the oil pump, reinstall the torque converter and then install the entire thing back into the rig. If you are at it, and pull the transmission out, then replace the oil filter, valve body and the solenoid pack as well, and add oil pan temp sensor for sake of long term reliability. Also, it might be a good idea to drop a new torque converter, if you can find good and cheap one.
Look, most of the shops don't repair transmissions, they just replace them. They take yours, send it to rebuild to transmission shop, and install back, ir simply buy a rebuilt one and use yours as a core.
I haven't had a 42RLE apart, but the input section rotates with the torque converter, which probably includes the first 2 or 3 clutch packs & possibly a planetary. Park prevents the final output section from turning. I'd have to look at the innards to know for sure, but park is basically neutral with the output section locked; the input section spins with the pump/TC/flexplate since they're all mated.
That doesn't change anything about your diagnosis though, the things most likely to make noise (imho) are the torque converter & trans pump. And then the flex plate. They said the TC was ok but I don't actually know how to test one. It usually just gets replaced as part of an overhaul. If you're convinced it's transmission, drain the fluid & inspect the pan. If it's got crap in it, then figure out where the crap came from because it's probably your problem.
I assume the transmission shop opened up the pan and checked the magnet and filter. If it is a planetary, I assume that that there will be excessive amount of metal in the transmission magnet.
The transmission shop did pull the pan. No metal found in the pan, just "clutch material that is normal for the miles on the transmission." So outside of it having 174k miles on it (and the noise it makes), nothing really pointed them to it needing to be rebuilt. Even though they tried to sell me on one.
Dude, I replaced transmission at 103K miles. Your survived to 174K, this is a lifetime achievement award
Similar threads
