Archived 47RE rattles when sitting still and in reverse?

[HerbW]

My 47RE auto transmission rattles very loudly when I put it in Reverse and just sit still with the brake on. It will do it in Drive also but barely. I need to get it figured out as I need to go back to work and need my truck to do it. I don't hear the rattle when I'm in neutral. I tried to find noise with an automobile stethescope but hard to pinpoint. I wonder if I have a loose or lost convertor bolt as I put this one in two months ago.



I'm afraid to drive it very far with this going on. Any ideas? There shouldn't be too many parts moving in my transmission while sitting still. Thanks, HerbW

 

[JLandry]

Does this rattle change in frequency or pitch with an increase in engine rpm?



Does the transmission seem to operate and shift normally in every other way?



By chance is the dust shield bent at the lower front of the transmission?



As to ideas... I've read that a cracked flex plate (drive plate) can make quite a racket.



It might be worth pulling the pan to check for metal debris.



Regards,



John L.

 

[PToombs]

I suspect the flexplate/ converter area as well. When you put it in gear, you are putting more pressure on the converter, which will move it out a little. Plus, it is side loading it when it's in gear.

 

[MFranz]

Open up the inspection plate under the Bell housing,Where the transmission bolts to the Engine. Look for metallic residue. The converter bolts can come loose

and even come completely out creating havoc. I had one come completely out

and crack my Billet flex plate. The answer is I hope Red Loctite. When I reinstalled my Flex Plate and Torque converter I used Red Loctite. So far no problems.

Good Luck

Mike

 

[HerbW]

I used blue loctite on the bolts. One bolt was iffy when I installed it and I replaced it. The new one seemed to torque right up okay. I almost pulled the converter and installed a helicoil in the hole because the first few threds were toast in the billet converter. I took off the inspection plate last night and all looked clean and fine inside as far as I can see. I broke an inspection cover bolt last night so it's off while I test it. Last night as the transmission had warmed up, the noise was gone. Today it's really loud with the plate off while in reverse but is getting quieter as it warms up. Sounds quiet in drive and neutral though. I may buy another converter, pull all the works out and start from scratch. Can noise in the converter area be different in reverse than neutral and drive? Any tests to tell where I need to go before I spend a fortune?

 

[HerbW]

Mike, Was there any visuals before removing the transmission? Was it obvious when you pulled it? thanks, Herb

 

[HerbW]

Oh, the noise sounds like metal hitting metal. A klack, klack sound that changes with RPMS! If I drive the truck it all sounds fine and everything works like it should. Idling brings it on.

 

[HerbW]

I just drove it to town and back. I could lightly hear in drive then it quited right up. Quiet even in reverse. The clank will return when it cools.

 

[HerbW]

I checked all the torque converter bolts and they were all tight and proper torque. I also fixed the cover plate holes and reinstalled cover. I examined as much of the flex plate as possible and it all looked fine. Maybe inside the converter is coming apart? I tried testing it in reverse for noise and it sounded normal. It's all warm though. Will try tomorrow after a night of cooling.

 

[MFranz]

Herb,I actually found a sheared off torque converter bolt when I removed the inspection plate. Some of the bolts were loose on the converter. I had used blue loctite . When I reinstalled I used Red Loctite. I also had a stripped out bolt hole in the torque converter. I took it to a machine shop and had them put in a Helicoil. This was after me trying to do it myself. I had read a post where someone said to use Loctite on the Helicoil . I asked the machine shop about this and they said no. Now I wish that I had because the Helicoil just spins after a certain amount of torq. It seems to be holding so far but I'm concerned its going to be a problem when I go to take it out. With regards to noise my truck was making intermittent noises that sounded like a bucket of bolts being tossed around. What did your flex plate look like when you had your transmission out. I know that those can crack and make some pretty strange sounds intermittently. When mine was cracked it would make various

sounds depending on the RPM of the engine. Its a common problem. The only way to find out unfortunately is to pull the Transmission.



Good Luck

Mike

 

[MFranz]

If your in the market for a new Trans you might check out DTT in British Columbia. If you call them and tell them your problem they might be able to help you out. Ask for Bill he's the Guru when it comes to Transmissions.



Mike

 

[HerbW]

Mike Franz,

Is Harry Piers there also? Is that Bill Goerand(spelling?). I have my original transmission sitting in the barn that if I can get a good rebuild kit from DTT or somewhere and do it myself before I tear my truck apart. I've rebuilt everything but an auto transmission in my life. My old transmission was good but I wanted a tuffer one as the old would slip some when pulling any weight. I changed to ATF-4 and the slipping quit. Hopefully, I'll see something when I pull the transmission again. I want to have a good idea before I tear it out as I have more time than money. Too bad it's not a stick shift. I think sometimes I made a poor choice to buy an auto transmission. Where does the flex plate crack at? I looked at the perimeter thru lower inspection hole for 360 degrees and where the bolts go into converter and all looks good.

 

[MFranz]

Herb,

My Flexplate had a hairline crack. It was hard to see at first. It was

a lot thicker then stock. My understanding is the stock ones are prone to crack,especially if you have modified the engine or drive it hard. Same goes for the transmission.

If you buy a transmission or a rebuild kit from DTT you will have better then a

manual transmission from what I hear. Do a search on TDR under Flex Plates

and you will see there's a lot of issues.







Mike

 

[MFranz]

I couldn't have seen the flexplate crack until the transmission was pulled.

Actually I dont think I saw the crack until I pulled the flexplate. If you do end up pulling the flexplate you should go ahead and replace the rear seal. I

didnt the last time I pulled the transmission and now my rear seal is leaking#@$%!



Mike

 

[HerbW]

Mike, Good idea to change rear seal I'll have to read my service manual to see how to do it. What about the rear freeze plug? I've kept my anti freeze changed and tested. I started my truck yesterday with inspection cover off and in put it in reverse. The noise is definitely louder with cover off. The sound is definitely in the converter, flexplate area. Could the pump or converter make such a racket? My truck drives perfectly normal other than the sound of bolts tumbling when in reverse. I hope it's the flexplate.

 

[MFranz]

Herb,This is a thread that I started awhile back when I had an Issue with my truck. Hope it helps.

Merry Xmas

Mike

 

[MFranz]

Looks like the attachment didnt make it into my post. Still trying to figure out how to do that. Oo.

 

[MFranz]

This is the thread I was referring to: https://www.turbodieselregister.com.../209979-rattle-bell-housing-transmission.html

 

[MFranz]

Heres another post that may be helpful. https://www.turbodieselregister.com...1751-install-billet-flex-plate-bolts-oem.html