Engine/Transmission (1998.5 - 2002) Rattle from Bell housing and or Transmission

[MFranz]

I have a intermittent Rattle/Knock coming from under the engine near the Bell housing or Transmission. Its happened a few times. Once when I first started up,other times when the engines warmed up. Its loud enough to be heard over the regular engine noise. Did some searches of past post. My concern is that it might be coming from the thrust bearing. If it was related to a bearing or connecting rod or in general that area would it not be happening every time I started the engine. Where do I start when troubleshooting. Could it have anything to do with an Injector. I'm concerned this is going to be a major repair. Thanks in advance for your responses.

Mike

 

[fox]

Check for loose converter bolts.

 

[hsmith]

Possibly a cracked flex plate.

 

[DCreed]

pull the cover on the pass side bell adapter plate and check the converter bolts if ALL are torqued to spec then the flex plate prolly cracked.

 

[MFranz]

Thanks for the replies everyone. The next step for me is to check the Torque Converter Bolts. I had put Loctite on them when I installed the transmission last and Torqued them to specs. If they are loose is it possible there is damage that cant be seen through the inspection plate?The Flex Plate is a Billet one from DTT. Looked pretty solid. Cant imagine that broken. I haven't been doing sled pulls. Has anyone known of problems created by using a Billet Flex Plate?I'm assuming that I will have to pull transmission to inspect the Flex Plate.

Thanks,Mike

 

[HBarlow]

If you weren't sledpulling it is extremely unlikely you broke the machined billet DTT flexplate (actually flywheel). They are far stronger than the OEM flexplate.

I had the same experience you described in my 2006 Ram with a full DTT 48RE with DTT flexplate a couple years ago, shortly after the full DTT transmission rebuild by a TX rebuilder. The flexplate bolts had worked loose and it made an awful rattling racket just like you described.

I'm not a machinist but I suspect some minor detail about the way the DTT flexplate is machined or maybe because the DTT torque convertor and transmission shift so much firmer contributes to the problem.

Once the bolts were retightened using thread lock mine was fine.

 

[MFranz]

Harvey,Thanks for the response. Was your Rattle problem intermittent or was it a constant Rattle. Mine has so far only done it a few times. I'm trying to imagine bolts coming loose and only making this noise occasionally.

Thanks Again

Mike

 

[EBung]

I have an intermitent chirp screach sound that happens only at about 1200 that is coming from the bell housing area and I think its the transmission lines rubbing together or rubbing something else. I am going to check my flexplate/converter bolts though.

 

[DCreed]

mine started out intermittent then as the bolts loosened it got louder and more often until I thought it was a rod knock! nope just loose bolts.

 

[MFranz]

Thanks everyone. As soon as the pavement warms up Im taking a look.

Thank you

Mike

 

[MFranz]

Bingo!!!!!

That's what it was. Loose Torque converter bolts . One of them came completely out and was tore up pretty good. Another one was loose enough to start rubbing against metal and a few others were just loose. I think I found just one bolt that was tight. My concern is the the hole that the torn up bolt came out of is out of round on the outside part,I believe the area that the bolt tightens to. The threads seem OK but the part where the bolt rests is not flat and out of round. What do you think,can I get by with just the other bolts if I have to. I used thread locker last time. Is there anything better. Does this happen on stock trucks.

Thanks for all the feedback. Its been most helpful. At least its not a major engine issue.

Thank You

Mike

 

[MFranz]

Its Back!!!!!!!!!!!!!!!!!

Another Vibration/Knock seems to be coming from the Bell housing or Engine. It seems to happen mostly at a certain RPM. Around 1000. I will have to take a look tomorrow and see if the Torque Converter bolts are still tight. Maybe the Flex Plate was damaged when the one Torque Converter Bolt broke off.

Stumped. Your Thoughts.

Thanks,Mike

 

[HBarlow]

When I had that experience I tightened the bolts then took it back to Texas to the transmission rebuilder. He pulled the transmission and replaced the DTT flexplate with another and carefully tightened the bolts using quality threadlock material. He expressed the opinion that the bolt holes were egg-shaped by the lossening experience. It never loosened again.

 

[jeepit]

You know I have this ratteling sometimes when I let out the clutch at certain rpms. Just loose bolts somewhere?

 

[DCreed]

You know I have this ratteling sometimes when I let out the clutch at certain rpms. Just loose bolts somewhere?

may be pilot bearing or clutch hub.

 

[jeepit]

may be pilot bearing or clutch hub.

Not sure. It sounds like tin ratteling...

 

[MFranz]

Pulling transmission

Harvey,when they replaced your flexplate after the first was damaged did they replace it with a DTT flexplate?Do you remember the name of the transmission shop in Texas that you used?I am pulling my trans and I'm thinking that this could be my problem too. Loose bolts on the Flexplate. I'm guessing that with all the torque that these engines put out along with all the vibrations that go with it you end up with this kind of problem.

Thanks everyone for the response. Take Care



Mike

 

[MFranz]

Harvey,

Was hoping to get the name of the Texas transmission shop to see what they would recommend to do if my problem ends up being the same as yours. I'm pulling my transmission this weekend and I will know then if it is the Flex Plate. I was talking to a mechanic today and he was telling me that he picked up an engine for cheap from a dealer(Gas Engine) that had been diagnosed as having a bad connecting rod. He thought what the heck fix the rod and he's got a good engine. Turns out it was a cracked Flex Plate that made all the racket.

The engine was fine. Oo. Oo. I just want to find the most bullet proof way to install this thing.

Thanks,Mike

 

[MFranz]

Flex Plate cracked.

Well pulled the transmission and found a couple loose bolts on the flexplate.

After taking the plate off found that it was cracked. There was a line that went bolt hole to bolt hole for about 6 holes and then curved towards the center hole of the plate. Talked to Bill at DTT and he said never heard of one

of the Billet ones cracking. I don't do tractor pulls. I tow a travel trailer only occasionally,and for performance enhancements I have a Smarty. Not big horsepower but responsive.

What do you think?Any one else have a cracked High performance Flexplate.

Should I go with the same. What do we think of a laminated Fexplate.

Any ideas on what caused it to crack. I think I had more miles on the stock flex plate then the Billet one.

Thanks

Mike

 

[MFranz]

Anyone have an issue with a cracked High Performance Flex Plate. If so what do you think caused it and how did you fix it. Doing research on the Internet

I have found a lot of info on all sorts of vehicle's with cracked Flexplates.

As the name implies (Flex Plate) would led me to believe that there is a certain amount of Flex (movement) that goes on here. Your thoughts.



Thanks

Mike