T-400 intermittent squeak rattle in park and drive - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Transmission - Rearend
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 10-14-2012, 12:42 PM
Registered User
 
Join Date: Mar 2011
Location: las cruces n.m.
Posts: 16
Wiki Edits: 0

Thanks: 3
Thanked 0 Times in 0 Posts
T-400 intermittent squeak rattle in park and drive

hello everybody. i posted a question before on hotrodders, and got some awesome help. so thankful for this site.

i've got a new problem, this time with my transmission. (i think)

I have an '85 chevy 3/4 ton 4x4. engine is a 402. tranny is a th400 that works great aside from being a little slow to go into reverse, and a slight leak from the the pump o-ring. (i think)

Here's the problem: When i start my truck, after the temp sensor on the block hits 150 +-, i hear what can only be described as a squeak/rattle. (sounds like a spun bearing almost, but it is very 'chirpy'.) It is intermittent, and usually goes away a couple of minutes after the thermostat opens up. the sound occurs in park, while the engine is at a fast idle, and also occurs in drive while at any speed, but goes away when i increase rpm's. The sound is definitely coming from the front of the transmission as determined by the screwdriver to ear test.

i call it a squeak/rattle, because it seems squeak more when going over rough patches in the road. again, the transmission seems to work fine, but the sound is getting louder, and i am beginning to notice a vibration while accelerating uphill. (no vibration apparent upon release of gas pedal.)

also, the torque converter has a bit of a wobble to it, which it has had ever since i bought the truck two and a half years ago.

One more thing to add: the other day it rained, and i drove in the rain, thoroughly wetting my undercarriage. The sound went away, and did not occur again for a couple of days. This caused me to think it is something external, but perhaps the humidity did something? I live in the dry desert of southern new mexico.

Sorry for all the words, but i have been searching hi and lo on many forums, and am about to pull the tranny, but just thought i'd put my problem out there.

I have tightened the flexplate to converter bolts, which were a little loose. i did not see any cracks. i have a suspicion that my TC bolts may be loose, thus causing the wobble?
Any suggestions would be greatly appreciated.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 10-16-2012, 06:47 AM
SSedan64's Avatar
Registered User
 
Last photo:
Join Date: Dec 2007
Location: Macon, GA.
Age: 50
Posts: 6,016
Wiki Edits: 0

Thanks: 0
Thanked 46 Times in 46 Posts
Flexplate to Converter bolts are the same as TC bolts. Did you intend to say Flexplate to Crank bolts?
If the TC was wobbling the TC nose may have been rubbing the rear of the Crank. Could also cause Trans Pump, Seal & Bushing damage.
Reply With Quote Quick reply to this message
The Following User Says Thank You to SSedan64 For This Useful Post:
oldhickory (10-24-2012)
  #3 (permalink)  
Old 10-16-2012, 04:30 PM
Registered User
 
Join Date: Mar 2011
Location: las cruces n.m.
Posts: 16
Wiki Edits: 0

Thanks: 3
Thanked 0 Times in 0 Posts
Yes, i meant flexplate to crank bolts. I decided not to pull the tranny yet, but instead replaced the filter and so far (day two) the sound has not come back. But i did find 3 or 4 very thin aluminum shavings, as well as a gray film in the bottom of the pan mixed with lots of gold colored 'dust'.

I noticed yesterday that i am missing one bolt to the bellhousing, and there is a small gap between the bellhousing and block on the passenger side (1/8"). Can this be the cause of the issues i am experiencing?
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 10-17-2012, 04:38 AM
SSedan64's Avatar
Registered User
 
Last photo:
Join Date: Dec 2007
Location: Macon, GA.
Age: 50
Posts: 6,016
Wiki Edits: 0

Thanks: 0
Thanked 46 Times in 46 Posts
It could be causing alignment issues. Also make sure the alignment Dowel Pins in the Block are there. 1 on each side.
Reply With Quote Quick reply to this message
The Following User Says Thank You to SSedan64 For This Useful Post:
oldhickory (10-24-2012)
  #5 (permalink)  
Old 10-24-2012, 08:28 PM
Registered User
 
Join Date: Mar 2011
Location: las cruces n.m.
Posts: 16
Wiki Edits: 0

Thanks: 3
Thanked 0 Times in 0 Posts
All of the bellhousing bolts were quite loose, so i pulled them and replaced them with new grade 8 bolts and lock washers. It has been almost two weeks since changing the filter, and the sound has not come back. Thanks for the help guys.
Reply With Quote Quick reply to this message

Tags
filter, rattle, squeak, th400, torque converter

Recent Transmission - Rearend posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last 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.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
car idles 1300 in park 600 in drive why? 23 tbucket Hotrodding Basics 49 09-17-2012 07:59 AM
pontiac 350 idles at 1000 rpm in park 600rpm in drive starin Engine 11 07-20-2012 06:16 AM
Intermittent drive and overdrive in 4L60E tamatt79 Transmission - Rearend 1 04-24-2010 10:34 PM
Is this delay from park to drive a big problem on TH350? shockers69 Transmission - Rearend 1 08-02-2004 04:27 PM
Engine wants to die from park to drive Siggy_Freud Engine 4 06-03-2004 11:21 PM


All times are GMT -6. The time now is 09:03 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.