4t80e Cadillac Transmission Problems? - 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 05-08-2008, 11:46 PM
Registered User
 
Join Date: May 2008
Location: virginia
Posts: 15
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
re 4t80e caddy trans problem

the 4t80e uses a band for fourth gear.problem? i say this becouse it does shift but slips. the computer your using is it from the same car as the motor ?if so when it sees a fault 4th is disabled. in the vehicle there is away to shift the trans on command with the temp controler.what do the codes you get mean? also there is a relearn function you must do for proper pcm controled shifts if the battery has been disconected you need to reset the shift learn this trans has no ajustable clearences in the clutch pack when you build them by the book.the computer makes up for any clearance problems with a shift relearn so it can see the volumes needed for each perfect shift.the solenoids also have a habit of breaking at the base were it ataches to the vb becouse of the black square top filter popping up under pressure if this is a problem there is a hold down for the filter through transtar.try fixing any engine codes before a this too. good luck

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 05-10-2008, 08:14 AM
Registered User
 
Join Date: Aug 2005
Location: Tampa, Florida
Posts: 2
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
4T80E no 4th

Everything is the same except the valve body was taken apart and it worked fine prior to the shift solenoids going out. I can buy a new valve body cheap if this could be the problem. Cadillac told me they don't replace the solenoids, they replace the whole valve body because of problems putting it back together??? The get $1000, I paid $300 for the solenoid job.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 05-12-2008, 08:24 PM
Registered User
 
Join Date: May 2008
Location: virginia
Posts: 15
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
no 4th gear

Did the solenoids break or did they go bad? The other thing is does the valve body and separator plate match? I just built one that had a plate from an earlier model that had blocked ports when you lined up one to the other,it also slipped in 4th but the B solenoid was broken and scorched clutches metal & friction material made some valves stick too. If you have engine codes the pcm maynot allow 4th.The 4t80e has a capability to read its own pressures through a snap-on scanner maybe able to watch what the shift is doing or even be able to sea if the pcm is telling the trans to shiftup ?who did the work&how long ago,warranty?One more thing have you tried shifting it with the computer it has an over ride in the diagnostics you can do in the car without scanner.if none of this points in the right direction you might have to pull the valve body and look for misassemled valve assemblies a washer on the wrong side of the spring will make it have no pressure on boost valve in the pump that was my lesson with my 1st 4t80e. also knicks on valves,grooves on accumulator pins&bores torn gaskets will give problems. good luck.

Last edited by will22; 05-12-2008 at 08:33 PM.
Reply With Quote Quick reply to this message

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:
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



All times are GMT -6. The time now is 11:13 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.