Tranny dropping out of gear? - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


1987-1991 Parley with regards to your 1987 to 1991 Bonneville, Olds 88 or Buick Le Sabre Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

Reply
 
 
 
Thread Tools Search this Thread
Old 10-21-2005, 05:48 AM   #1
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
Join Date: Feb 2005
Posts: 13
Thanks: 0
Thanked 0 Times in 0 Posts
Blylock is on a distinguished road
Default Tranny dropping out of gear?

My 87 bonny when using steady throttle on the highway, seems to drop out of gear, or its the TC unlocking. It does it in 3rd and OD under no load, even feel it when im slowing down (no brakes, just taking my foot off the gas). i notice a 3-500 rpm jump, and you can physically feel the TC unlocking, then about 5 seconds later, it locks back up and the RPMs go back down. It unlocks at least once every 30 seconds in either gear. Any ideas?
Blylock is offline   Reply With Quote
Old 10-21-2005, 02:54 PM   #2
Senior Member
Posts like a Turbo
 
Join Date: May 2005
Location: Fredericton, New Brunswick.
Posts: 380
Thanks: 0
Thanked 1 Time in 1 Post
Timothy's Buick is on a distinguished road
Default

How are your engine temps? Thermostat changed recently?
Timothy's Buick is offline   Reply With Quote
Old 10-21-2005, 07:21 PM   #3
Senior Member
Posts like a Camaro
 
padgett's Avatar
 
Join Date: Jul 2003
Location: Orlando, Florida
Posts: 872
Thanks: 0
Thanked 0 Times in 0 Posts
padgett is on a distinguished road
Default

When you take your foot off the gas (TPS under 2.5%) or touch the brake (is the brake switch adjusted properly ?), the TCC is supposed to unlock. DFCO will then jump the RPM.

Other than that, if the coolant temp drops under 146F (can check with a scan tool) the TCC will unlock also.
padgett is offline   Reply With Quote
Old 10-21-2005, 09:43 PM   #4
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
Join Date: Feb 2005
Posts: 13
Thanks: 0
Thanked 0 Times in 0 Posts
Blylock is on a distinguished road
Default

my concern is the repeated (every 15 seconds or so) on steady throttle, the unlocking feeling, and the rpm jump. unless the temp is going under 146 every 15 seconds, the TC should stay locked.
Blylock is offline   Reply With Quote
Old 10-21-2005, 10:05 PM   #5
Senior Member
Posts like a Corvette
 
Ol' Timer's Avatar
 
Join Date: Oct 2002
Location: New Jersey - Most of Our Elected Officials Have Not Been Indicted
Posts: 1,483
Thanks: 0
Thanked 0 Times in 0 Posts
Ol' Timer is on a distinguished road
Default

I wouldn't lose too much sleep over this. The operation of your TCC sounds normal too me. Mine does the same thing when I'm doing a "Steady" 65mph. I constantly hear it going in and out of OD(unlocking/locking the TCC). You may not realize that you are taking you foot off the gas ever so slightly and still remaining at speed. Not to worry. Enjoy the ride.
Ol' Timer is offline   Reply With Quote
Old 10-22-2005, 08:00 AM   #6
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
Join Date: Feb 2005
Posts: 13
Thanks: 0
Thanked 0 Times in 0 Posts
Blylock is on a distinguished road
Default

i just find it odd that ive driven this for 20k miles and all of a sudden its doing it, and its doing it when im not in OD
Blylock is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
FYI if you lose 4th gear / no fourth gear / no 4th gear caminated2k 2000-2005 6 07-24-2005 11:26 PM
Why dropping the clutch isnt good on FWD vehicles (Saturn) Spiral General GM Chat 4 04-16-2004 05:32 PM
Wal-Mart dropping BulldogSecurity stuff? acg_ssei Audio (and aftermarket electronics) 5 03-03-2004 11:12 AM
Just dropping the front by an inch? Bassplayincrowe Performance, Brainstorming & Tuning 4 02-24-2004 08:04 PM
RPMs dropping at 50-70 MPH 74747474 1992-1999 10 10-06-2003 11:49 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not 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 Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 11:55 AM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.