Grinding Sound After Flexplate Replacement

Whats up everyone? I have a 2002 tacoma in the shop right now. Its a 3.4, auto. Came in for a ticking/slapping sound at idle once it was warmed up. We inspected the Flexplate and found it was cracked. I ordered part #FRA-465 from Autozone, its made by Pioneer. Anyways, same tooth count, looks identical. After reassembling the truck it makes a grinding sound upon startup, only when cranking. I ordered a new starter, even thought the old one tested good, but its making the same sound. The motor turns freely by hand with no grinding sounds, no damage on the flex plate that I can see from the inspection port. From my research at this point I am seeing that some of these after market flex plates will push the converter a few MM further into the bell housing and can cause the converter to make contact with the housing. Ive read 1 thread that said this happened to them. Anyone else have any ideas or experience the same thing?

 

Can you video it?

 

I should have taken a video of it. We are already taking the transmission back off right now.

 

The noise sounded like the starter recoil spring wasn't fast enough to disengage the flex plate before grinding. A squealing sound.

 

So we got the fly wheel out. Looking at it next to the one we took out and trying to find some differences we noticed that from outside to outside the old gear was exactly 12", the new one is 12 1/16. They are the same depth, same tooth count. Just the new one is slightly larger.

 

Can you shim the starter? Or get an oem flexplate from a salvage yard or new from dealer.

 

We shimmed the starter before we dropped the transmission again. That didnt help at all. I was wrong about the measurements, they are both exactly 20" in diameter. Behind the torque converter looks clean, no signs of rubbing or damage between it and the bell housing.

 

Just in case...

Did you measure to be sure the TC was seated completely? I wouldn't rely on just the 3 bumps/clicks method.




Also, when bolting up the TC, did you start with the black bolt first? Must start with the black first.

 

Did you see any Marks on the starter drive teeth or the flex plate ring gear.

I had a similar noise on my Denso reman on my 5 speed after a few cranks it quit been a few years no problem.

 

Well, lol. We just took it out again, for the 3rd time now. Measured the depth of the torque converter bolt holes from the bell housing and they are all greater than the .7" spec. Looked inside the holes and dont see any damage indicating wrong bolts were ever installed. We used the exact same bolts we pulled out initially, 100%. Everything was torqued to spec. All our torque converter bolts are the same color.

No visible damage to the starter or flex plate ring gear anywhere. We have started it about 15 times now between the 2 installs, the sound is persistent.

After an in depth comparison of the two flex plates side by side they are exactly the same. Same manufacturer and everything. I dont think the one we took out initially was the factory one, it has "made in Mexico" stamped on it.


The cracked flex plate didnt have the issue with the starter that we are having now. Which leads me to believe that we are having an issue with something else. Like maybe the torque converter is wobbling, and that is what caused the flex plate to crack in the first place?

 

I am gonna go smoke a cigarette and contemplate life for a few minutes. When I come back inside I'll make a video and upload it to see what you guys think.

 

Weird. I have an 02 with the 5VZFE and one of my TC bolts is black. The ridge is very evident at the base of the bolt. Maybe the owner worked on it at some point and sub'd in different bolts.

Here are my bolts - it can be hard to see at first glance but there is a difference in color for one. In the pic its much more evident. The "black" bolt has a ridge at the base and the others do not.

Anyway, hope you track down the issue you're having.

 

This may or may not be helpful, but I did run into a similar grinding / screeching / rotational noise in that area.

While doing a 4x4 conversion, pulling the trans, torque converter, starter, I decided to replace my starter. Toyota supplied me with a normal spec starter, while my truck original had a cold spec starter. For some reason or another the starter had an interference issue with the flex plate. Upon start up and idle the vehicle produced a rotational screeching noise, not a bad impending doom noise but definitely not a good noise. While turning over the motor by hand I could hear a light ticking noise coming from the bell housing / starter location. I resolved this by reinstalling my original cold spec starter. See the quote below and photo reference. Hope this is helpful, or at least something to rule out.

 

Thank you for those pics. We figured out which one was the "black" one, ours all look the same color but one does have that ridge. I cant say that we used that black bolt first or not. Would it make that much of a difference if we hadn't? I mean if all the bolts were in and torqued down to spec wouldn't it be aligned?

The reason I am not focusing on the starter is because this issue wasn't present prior to replacing the flex plate and we have the same problem with the original starter and now with a replacement. I did look to see and the replacement I ordered is for a "cold weather package".

 

Toyota says it does. That ridge helps to pull the flex plate and torque converter into alignment.



I would follow toyota on this one. Black first - torque it to spec (30ft lb) and then each one after the next.

 

I'm going to drop this link here in case you want to explore other options.

https://www.tacomaworld.com/threads/flex-plate-drive-plate-for-a340f-trans.670514/

 

https://youtu.be/WgSTd1DbfIk

 

We did end up finding the black alignment bolt like I mentioned earlier.

 

Message sent.

 

how is the center shaft in the transmission ?
also how does the seal look ?