4T80e troubles
Cadillac
 

Cadillac Forums | Help Us Help You | Advertise | Cadillac Parts | Cadillac News | Cadillac Classifieds / (Old System)

Cadillac Technical Archive | Cadillac Dealers | Cadillac Reviews | Cadillac Dealer Reviews | Cadillac Vendors

CadillacForums.com is the premier Cadillac Forum on the internet. Registered Users do not see the above ads.
+ Reply to Thread
Results 1 to 7 of 7
Like Tree1Likes
  • 1 Post By Aztec ETC ECS
Cadillac DeVille 1985 to 2005 including:
1985-1992 Fleetwood, 1993 Sixty Special, All FWD Forum Discussion, 4T80e troubles in Past Cadillac Vehicle Discussion; have a 1995 Deville Concours that suddenly dropped out of 4th gear to 2nd gear and only drives forward in ...
  1. #1
    95cadconcours is offline Cadillac Owners Member
    Automobile(s): 1995 Cadillac Deville Concours
    Join Date
    Jun 2013
    Age
    56
    Posts
    2

    4T80e troubles

    have a 1995 Deville Concours that suddenly dropped out of 4th gear to 2nd gear and only drives forward in 2nd now. First code that came up was P094, I changed out both shift solenoids and made sure that the internal wiring was in good shape and connected properly. Cleared all codes and took out for drive, still preforms as it did before repairs but new code is P029. I have removed and cleaned the Vehicle Speed Sensor, verified ohms at 1501 with in proper range. Reinstalled VSS and cleared codes and drove, now have P029 code again and the same drive as original problem. I have looked for loose connectors and bad wiring and found no problems. My research has found that the PCM has put the tranny into a fail safe mode. Anyone have any suggestions? I am 2nd owner of car and it has 123,000 miles on it now.

  2. Remove Advertisements
    CadillacForums.com
    Advertisements
     

  3. #2
    Ranger's Avatar
    Ranger is offline Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    72,740

    Re: 4T80e troubles



    When you replaced the shift solenoids, did you order the "kit" and install the support bracket.

  4. #3
    stoveguyy is offline Cadillac Owners Connoisseur
    Automobile(s): 96 STS, 140k
    Join Date
    Aug 2007
    Location
    mpls mn
    Posts
    2,482
    I have looked at 10 4t80 trans and not 1 had a strainer that was pushed out of the valve body. I think the belief that the special retainer fixes all issues with the solenoids is overblown. I have seen many without the retainer and some with and all had the strainer in place.

  5. #4
    95cadconcours is offline Cadillac Owners Member
    Automobile(s): 1995 Cadillac Deville Concours
    Join Date
    Jun 2013
    Age
    56
    Posts
    2

    Re: 4T80e troubles

    Quote Originally Posted by Ranger View Post


    When you replaced the shift solenoids, did you order the "kit" and install the support bracket.
    No I only replaced the solenoids, after the repairs stated I have checked and the original solenoids are still good as far as ohms go and neither were broken or sitting out of position.

  6. #5
    Aztec ETC ECS's Avatar
    Aztec ETC ECS is offline Cadillac Owners Connoisseur
    Automobile(s): '02 ETC ECS#533, '05 Escalade, '05 AWD Magnum, '74 455 OLDS
    Join Date
    Feb 2012
    Location
    NYC
    Age
    47
    Posts
    1,851

    Re: 4T80e troubles

    Quote Originally Posted by stoveguyy View Post
    I have looked at 10 4t80 trans and not 1 had a strainer that was pushed out of the valve body. I think the belief that the special retainer fixes all issues with the solenoids is overblown. I have seen many without the retainer and some with and all had the strainer in place.
    Only 10?
    Get back to us after 1010.

    Quote Originally Posted by 95cadconcours View Post
    No I only replaced the solenoids, after the repairs stated I have checked and the original solenoids are still good as far as ohms go and neither were broken or sitting out of position.
    That will only work if you replaced them with the non-updated solenoids. I didn't even think they were available anymore. The old style solenoids are actually the screen retainer. That's why they break.
    "New" solenoids with no bracket installed will allow the screen to pop out.
    Sometimes, the crack in the old solenoid is not so obvious or may not even have one, might just flex with screen pressure on it. It will ohm check but not hold pressure.

    No codes?

  7. #6
    CadillacLuke24's Avatar
    CadillacLuke24 is offline Cadillac Owners Connoisseur
    Automobile(s): Alexandra - 96 SDV
    Join Date
    Jul 2010
    Location
    Middle of Nowhere
    Age
    23
    Posts
    4,818

    Re: 4T80e troubles

    He has P029.

    Not that you wanted to hear this, but you may have a harness issue. As in internal wiring harness issue. IF that is the case, you're looking at a $2,000 repair. Make sure all the wiring is snug and clean.

  8. #7
    Aztec ETC ECS's Avatar
    Aztec ETC ECS is offline Cadillac Owners Connoisseur
    Automobile(s): '02 ETC ECS#533, '05 Escalade, '05 AWD Magnum, '74 455 OLDS
    Join Date
    Feb 2012
    Location
    NYC
    Age
    47
    Posts
    1,851

    Re: 4T80e troubles

    Quote Originally Posted by CadillacLuke24 View Post
    He has P029.
    Sorry, was being sarcastic. Workin' on that.

    Again, if you put in "new" style solenoids without the the bracket, there is nothing to hold in the screen. It will come out & dump solenoid pressure.

    Also, "old" solenoids have a tab on them that holds in the screen. The bracket cannot be installed with old ones.
    CadillacLuke24 likes this.

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.
If you do not want to register, fill this field only and the name will be used as user name for your post.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

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.



Bookmarks

Cadillac Posting Rules

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
Read about Lincoln | Buick | Kia Forte Forum
Need products for your Cadillac? Check out your options at the links below:

custom floor mats | Cadillac Chrome and Black Chrome Wheels | window tinting