Automatic Transmission 2-Speed thru 10-Speed GM Autos | Converters | Shift Kits
Sponsored by:
Sponsored by:

4L80E TCC stuck locked

Thread Tools
 
Search this Thread
 
Old 04-19-2016, 01:05 PM
  #1  
On The Tree
Thread Starter
 
gothic_sera's Avatar
 
Join Date: Mar 2015
Posts: 172
Likes: 0
Received 1 Like on 1 Post
Default 4L80E TCC stuck locked

OK, so I fixed my other issues, it was a firmware issue with the controller. Now shifting properly...

I had a sneaky feeling all along that the TCC LU was stuck engaged - and I now know it is. Shift into D with your foot on the brake and it stalls the engine completely. Shift without applying the brake and it all works fine, as soon as you brake again it tries to stall.

I've checked the wiring to the TCC solenoid, and the resistance of the solenoid and they both check out OK.

Questions is, why?

The transmission is freshly built, by myself, it has the transgo HD2 kit installed per their instructions (with the exception of the pressure relief valve), it also has a new standard pump fitted.

The TCC was rebuilt by a reputable shop in the UK, so I expect that's OK.

Any ideas. Wondering if I got a checkball wrong in the case or VB maybe?

Last edited by gothic_sera; 04-19-2016 at 01:11 PM.
Old 04-19-2016, 02:12 PM
  #2  
Teching In
 
Ratdaddy60's Avatar
 
Join Date: Feb 2014
Posts: 27
Likes: 0
Received 0 Likes on 0 Posts
Default

http://www.sonnax.com/parts/1989-lub...egulator-valve

You may need to install this pressure regulator valve.
Old 04-19-2016, 02:23 PM
  #3  
On The Tree
Thread Starter
 
gothic_sera's Avatar
 
Join Date: Mar 2015
Posts: 172
Likes: 0
Received 1 Like on 1 Post
Default

Thanks, I've just ordered one from Rock Auto - hopefully it will be here before the weekend - depends on FedEx....

I've read mixed reviews about them - some people say they've fixed the problem, others say not. Hope it does, I really don't want to be pulling the transmission again....
Old 04-20-2016, 08:43 PM
  #4  
TECH Fanatic
 
clinebarger's Avatar
 
Join Date: Jan 2015
Location: Fort Worth, Texas
Posts: 1,116
Likes: 0
Received 31 Likes on 30 Posts
Default

Doesn't the HD2 kit instruct you too drill a Lube to Line bypass in the Pump Cover? If this step was done correctly.....DO NOT install that Sonnax PR Valve.
Have you installed a Pressure Gauge too verify proper pressure?
Old 04-21-2016, 12:57 AM
  #5  
On The Tree
Thread Starter
 
gothic_sera's Avatar
 
Join Date: Mar 2015
Posts: 172
Likes: 0
Received 1 Like on 1 Post
Default

Originally Posted by clinebarger
Doesn't the HD2 kit instruct you too drill a Lube to Line bypass in the Pump Cover? If this step was done correctly.....DO NOT install that Sonnax PR Valve.
Have you installed a Pressure Gauge too verify proper pressure?

It's listed as optional, and I didn't do it... Typical

I haven't put a gauge on it yet, will do after I've done the Sonnax mod. I can control the pressure from my laptop so should be able to check the PC solenoid is working properly too.
Old 04-21-2016, 05:45 AM
  #6  
10 Second Club
iTrader: (10)
 
alocker's Avatar
 
Join Date: May 2006
Location: NW Chicago Burbs
Posts: 1,166
Likes: 0
Received 3 Likes on 3 Posts

Default

Have you tried to keep the engine running by giving it a little throttle?
Old 04-21-2016, 06:20 AM
  #7  
On The Tree
Thread Starter
 
gothic_sera's Avatar
 
Join Date: Mar 2015
Posts: 172
Likes: 0
Received 1 Like on 1 Post
Default

It stalls almost instantly.

If you shift into D with the wheels off the ground without your foot on the brake and then accelerate and then jab the brakes it immediately tries to stall the motor. So I'm pretty certain the converter is locked

Last edited by gothic_sera; 04-21-2016 at 03:44 PM.
Old 04-21-2016, 03:01 PM
  #8  
TECH Junkie
 
98CayenneT/A's Avatar
 
Join Date: Nov 2013
Location: White Bear, Mn
Posts: 3,888
Received 345 Likes on 237 Posts

Default

Please correct me if I am wrong but wouldn't the tcc valve installed backwards cause the symptoms gothic_sera is having ?
Old 04-21-2016, 03:45 PM
  #9  
On The Tree
Thread Starter
 
gothic_sera's Avatar
 
Join Date: Mar 2015
Posts: 172
Likes: 0
Received 1 Like on 1 Post
Default

Originally Posted by 98CayenneT/A
Please correct me if I am wrong but wouldn't the tcc valve installed backwards cause the symptoms gothic_sera is having ?
Thank you for the suggestion! I plan to pull and replace the TCC solenoid while I have the pan off. While I am in there I will remove the TCC valve and check I reinstalled it the correct way

Sera
Old 04-22-2016, 02:48 PM
  #10  
On The Tree
Thread Starter
 
gothic_sera's Avatar
 
Join Date: Mar 2015
Posts: 172
Likes: 0
Received 1 Like on 1 Post
Default

The Sonnax valve arrived today and I pulled the pan and fitted it. Also replaced the TCC solenoid and checked the valve was in the right way round and free to move (which it was).

I also replaced both shift solenoids with new Delco ones while the pan was off. Couldn't hurt.

After first firing it up nothing seemed to have changed. However after running for a few minutes and then getting angry and putting it in drive with my foot on the brake and giving it a load of revs it all seems to be working... it now idles in gear quite happily. So that's a result.

I just have problems with my Megashift now - thinking of ditching it an using a TCI EZ-TCU if I can't get it working properly tomorrow. Trouble is I really don't have that sort of money to spend
Old 04-22-2016, 03:04 PM
  #11  
10 Second Club
iTrader: (10)
 
alocker's Avatar
 
Join Date: May 2006
Location: NW Chicago Burbs
Posts: 1,166
Likes: 0
Received 3 Likes on 3 Posts

Default

Just curious what fluid you run? I has similar issues stalling with regular hyguard when cold. Low viscosity hyguard helped immensely.
Old 04-22-2016, 03:10 PM
  #12  
On The Tree
Thread Starter
 
gothic_sera's Avatar
 
Join Date: Mar 2015
Posts: 172
Likes: 0
Received 1 Like on 1 Post
Default

I'm running normal Dexron 3, nothing fancy



Quick Reply: 4L80E TCC stuck locked



All times are GMT -5. The time now is 01:51 PM.