TRANNY RATTLES!! - Ford Powerstroke Diesel Forum
Powerstroke.org is the premier Diesel Truck Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 04-18-2012, 12:26 PM
Powerstroke.org Rookie
 

Join Date: Jun 2009
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Question TRANNY RATTLES!!

Hey everyone,

Ive been having issues with my truck for a while now.

1997 f-350 7.3 powerstroke turbo diesel, dually.
Manual Transmission


PROBLEM: My transmission rattles!!

DETAILS: After my truck warms up and im driving everything is fine.
When i stop at a red light or just make a stop, the tranny rattles
like its going to fall off. "BLAK,BLAK,BLAK,BLAK" The truck shakes as
well. Well when i rev the engine the the rattling stops and truck
sounds normal. Can some help me out or guide me to what the
problem might be. Thanks.!!


NOTES: The tranny rattles on and off. It doesnt happen all the time.
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2  
Old 04-18-2012, 12:44 PM
Compression Ignition Addict
 

Join Date: Oct 2011
Location: Tehachapi, CA
Posts: 1,540
Thanks: 0
Thanked 16 Times in 16 Posts
Feedback Score: 0 reviews
If you still have the factory DualMass FlyWheel (DMFW), it a likely culprit. The DMFW has two masses with dampening springs between them. The springs are to dampen vibrations from the engine. Many times the springs fail, the spring retainers fail, or the springs just get weak and the flywheels fail (which can cause vibration, rattling, mimic injectors "missing", and even crack transmission cases).

Replacing the DMFW is expensive just for the parts. Many folks opt to replace the DMFW and clutch with a Single Mass FlyWheel (SMFW)/Clutch kit. The kits are available from a host of suppliers (Luk, ValAir, SBC etc) and are generally cheaper than just the DMFW alone (no clutch). The clutches are not interchangeable between the two setups.

The advantages to a SMFW setup: More reliable, easier pedal compared to the DMFW, you can resurface them, and they're cheaper. Drawbacks: A bit noisier due to "gear rollover" noise and very low rpm and speed (lugging around in 1st or 2nd under 1500 rpm). Some find it objectionable, but I didn't mind (it is a truck).

You can check the DMFW by removing the flywheel inspection cover and look at the dampening springs to see if they are all there with the retainers. Try to counter-rotate the two masses against each other. Measure the distance of the counter-rotation at the flywheel rim. Anything more than 5/8" and it's bad.

Cheers!
Reply With Quote Quick reply to this message
  #3  
Old 04-18-2012, 01:25 PM
Powerstroke.org Rookie
 

Join Date: Jun 2009
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Hey Thanks for your reply!!!

Are there any images you can direct me to see what the dampening springs and retainers look like when bad?

How many springs are there supposed to be?

Can i check all this while the tranny is still on the truck?

Thanks,

Last edited by zalez; 04-18-2012 at 01:29 PM.
Reply With Quote Quick reply to this message
  #4  
Old 04-18-2012, 07:34 PM
Compression Ignition Addict
 

Join Date: Oct 2011
Location: Tehachapi, CA
Posts: 1,540
Thanks: 0
Thanked 16 Times in 16 Posts
Feedback Score: 0 reviews
Sorry, I don't have a picture. If you look up in there with a flashlight (tranny does not need removal ... just remove the inspection cover) you'll be able to see them and the end retainers. Just make sure they are all there (I forget how many maybe about 6 - 8?) and check the measurement too. Cheers!
Reply With Quote Quick reply to this message
  #5  
Old 04-18-2012, 09:45 PM
Compression Ignition Addict
 

Join Date: Aug 2008
Location: Madison, WI
Posts: 2,605
Thanks: 1
Thanked 34 Times in 33 Posts
Feedback Score: 0 reviews
Quote:
Originally Posted by Patrick Feeley View Post
Drawbacks: A bit noisier due to "gear rollover" noise and very low rpm and speed (lugging around in 1st or 2nd under 1500 rpm). Some find it objectionable, but I didn't mind (it is a truck).
The first time or two you drive the truck after the job, you'll chirp the tires and/or lug/stall it. Before you know it, the "brain in your leg" will learn the right clutch action to engage smoothly without lugging, and the rollover noise will diminish and/or you'll just tune it out.

Quote:
Try to counter-rotate the two masses against each other. Measure the distance of the counter-rotation at the flywheel rim. Anything more than 5/8" and it's bad.
This is the key. If any spring parts have come loose, they'll probably fall out when you remove the inspection cover. But this movement is the important thing. And to emphasize what Patrick mentioned earlier, the big risk is that the two masses will separate at speed, with bits of spring/retainer being thrown outward with great centrifugal force. That's what can crack the tranny case. And since there's no separate bolt-off bellhousing, it's the case for the WHOLE tranny that goes.
Reply With Quote Quick reply to this message
  #6  
Old 04-19-2012, 11:41 AM
Compression Ignition Addict
 

Join Date: Oct 2011
Location: Tehachapi, CA
Posts: 1,540
Thanks: 0
Thanked 16 Times in 16 Posts
Feedback Score: 0 reviews
I mostly noticed it when I would downshift into 2nd or 1st going slow (like when the fiver is hooked up). Just kind of startles you at first, but you get used to it (and tune it out). Cheers!
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Ford Powerstroke Diesel Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -8. The time now is 05:16 PM.


Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.1
Garage Plus, Vendor Tools vBulletin Plugins by Drive Thru Online, Inc.

vB.Sponsors