Grinding driveline noise with application of engine torque




Another thought is I wonder if an exhaust mount has broken and something is rubbing on the exhaust.
Any of you guys spent enough time underneath an E3504matic to have any ideas?




Another thought is I wonder if an exhaust mount has broken and something is rubbing on the exhaust.
Any of you guys spent enough time underneath an E3504matic to have any ideas?
If it does see see if you can hear it when reversing. Hard to go 20 mph reversing, that’s why I wonder if you could actually hear it at very low speed too.
If noise exist going forward but not reversing I suspect your transfer case bearing is failing again.




Thanks for the reply. I drove it over to the indy that repaired the transfer case a year ago tonight. I think as you suggest the noise is there at lower speeds as well as long as I apply sufficient torque. I also suspect you are right about it being the transfer case again though the noise is different this time. It was noisey independent of torque application last time but I have been hearing a very faint high pitched whine similar to a precurser last time it failed. It was fairly quiet at speed as long as I was not applying much load.
We shall see.




Thanks for the reply. I drove it over to the indy that repaired the transfer case a year ago tonight. I think as you suggest the noise is there at lower speeds as well as long as I apply sufficient torque. I also suspect you are right about it being the transfer case again though the noise is different this time. It was noisey independent of torque application last time but I have been hearing a very faint high pitched whine similar to a precurser last time it failed. It was fairly quiet at speed as long as I was not applying much load.
We shall see.




Last edited by MBNUT1; Oct 1, 2019 at 09:06 PM.








He now says it is the transfer case which was rebuilt a little over a year ago at another indy who I had look at this noise while it was under the year warranty and wanted to drain the diff fluid. We ran it on the lift today after the test drive and I agree that the differential is quiet and the transfer case is noisey. He claims the old differential was so loud that they couldn't hear the transfer case. Which bothers me because the car it doesn't sound any different to me during the test drive.
He showed me the fluid that they drained from it which had bits of metal in it. But for all I know it if you took every differential with 130K miles it would show the same thing. Obviously I will take it back to the guy who did the transfer case but I will be really surprised if he doesn't try to weasel out of fixing it.
The only good news is the new mounts have made the car really nice other than the driveline noise.
Any advise? I don't know why the customer should have to own the responsibility for a misdiagnosis.
Signed,
Totally Depressed.
Last edited by MBNUT1; Dec 19, 2019 at 07:03 PM.
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Last edited by MBNUT1; Jan 8, 2020 at 06:37 PM.




The noise you hear in this case would be the gear wheel teeth hitting each other with corners of the teeth and this can destroy the gear wheels so your Indy mechanic needs to go back to the gear box school to learn about this fact. You truly can cause much more damage by driving it.
The opposite mistake with these bearings is to set clearance too tight. Too tight setting can destroy the bearings themself that then send pieces of metal around and can really wreck havoc inside the box.
Don’t drive it before fix is my advice.




The noise you hear in this case would be the gear wheel teeth hitting each other with corners of the teeth and this can destroy the gear wheels so your Indy mechanic needs to go back to the gear box school to learn about this fact. You truly can cause much more damage by driving it.
The opposite mistake with these bearings is to set clearance too tight. Too tight setting can destroy the bearings themself that then send pieces of metal around and can really wreck havoc inside the box.
Don’t drive it before fix is my advice.
Hi Arrie,
Thanks for the response. I have been worrying about the potential damage to the gear teeth as well. I am worried that when they put it back together it is still going to be noisy.
We only have two cars so I don't have a lot of choice but I will drive it minimally.
He claimed that the premature wear was due to the clearances being too tight. He said he learned this from previous rebuild returns. I also brought up the issue of contamination. ( I am an hydraulic system engineer) His response was the same as previously in that the contamination will go to the bottom of of the transfer case (I have been worried that it would find its way back into the transmission and the control body in particular. The 4th to 5th shift has kind of a pause that I don't like.
Last edited by MBNUT1; Jan 9, 2020 at 10:08 PM.








Thanks for the response. I have been worrying about the potential damage to the gear teeth as well. I am worried that when they put it back together it is still going to be noisy.
We only have two cars so I don't have a lot of choice but I will drive it minimally.
He claimed that the premature wear was due to the clearances being too tight. He said he learned this from previous rebuild returns. I also brought up the issue of contamination. ( I am an hydraulic system engineer) His response was the same as previously in that the contamination will go to the bottom of of the transfer case (I have been worried that it would find its way back into the transmission and the control body in particular. The 4th to 5th shift has kind of a pause that I don't like.
if a bearing fails it means the race surfaces flake off. These flakes are very thin surface material flakes and is not the same contamination as what normally is found on the magnets in the pan. These flakes can easily move with oil and with bad luck can end up in a gear mesh between two gear wheels and that is when the real damage can happen.


