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

2-3 shift is going bad

Thread Tools
 
Search this Thread
 
Old 02-12-2008, 08:37 PM
  #1  
TECH Enthusiast
Thread Starter
iTrader: (20)
 
dubrado's Avatar
 
Join Date: Apr 2003
Location: texas
Posts: 658
Likes: 0
Received 0 Likes on 0 Posts

Default 2-3 shift is going bad

As i'm accelerating, right before it shifts from 2nd to 3rd....the car jumps up in revs. Literally right before it shifts. And depending on how much throttle I use the amount of rpms that it jumps, changes. For example, when i'm just cruising along it jumps up 1000rpm suddenly, right before it shifts. If i'm using more throttle it'll jump up 1500-2000 rpm.

Any ideas?
Old 02-12-2008, 08:43 PM
  #2  
LS1Tech Sponsor
iTrader: (25)
 
performabuilt's Avatar
 
Join Date: Aug 2006
Location: BLOOMSBURG PA
Posts: 10,858
Received 78 Likes on 56 Posts

Default

Could be a shift timing or tuning issue, (I answered your previuos thread) Or could be a trans issue. Tell us a little more. You mentiond you had a new trans/converter Whats the stall on the converter?
__________________
Built..PerformaBuilt..Tough

Call 888-744-6542


Old 02-12-2008, 08:47 PM
  #3  
FormerVendor
 
Gilbert@Ace Racing's Avatar
 
Join Date: Oct 2006
Location: D-F/W
Posts: 3,123
Likes: 0
Received 2 Likes on 2 Posts
Default

I'm afraid your 3/4 clutches are failing. Check the flui condition, is it full. Does i have a burnt pungeant odor?

I saw that this is a relatively new unit in your previous post. You might want to speak to the folks that built it and see what they have to say.

g
Old 02-12-2008, 08:51 PM
  #4  
TECH Enthusiast
Thread Starter
iTrader: (20)
 
dubrado's Avatar
 
Join Date: Apr 2003
Location: texas
Posts: 658
Likes: 0
Received 0 Likes on 0 Posts

Default

this is the old unit, which is stock, just a shift kit...just curious as to what it might be that failed in my old one before a new one goes in.

fluid is clean, not full all the way but in between the hash marks

trans has 55k and has been sprayed on a good amount
Old 02-12-2008, 08:59 PM
  #5  
LS1Tech Sponsor
iTrader: (25)
 
performabuilt's Avatar
 
Join Date: Aug 2006
Location: BLOOMSBURG PA
Posts: 10,858
Received 78 Likes on 56 Posts

Default

Just curious did you have a previos post after a cam PO101 ? This is a MAF code and could be the source of your present failure, And improperly calibrated MAF can affect trans line presure and result in a failure. I also noticed this occured after you did some engine mods
__________________
Built..PerformaBuilt..Tough

Call 888-744-6542


Old 02-12-2008, 09:13 PM
  #6  
TECH Enthusiast
Thread Starter
iTrader: (20)
 
dubrado's Avatar
 
Join Date: Apr 2003
Location: texas
Posts: 658
Likes: 0
Received 0 Likes on 0 Posts

Default

Originally Posted by performabuilt
Just curious did you have a previos post after a cam PO101 ? This is a MAF code and could be the source of your present failure, And improperly calibrated MAF can affect trans line presure and result in a failure. I also noticed this occured after you did some engine mods
I thought it might be but I've run the car w/the P0101 for a while w/no issues...so if it was that code it would have affected the trans immediately correct?

In my case it didn't. However after another tune w/no TQ management it gradually started to slip and then I put TQ management back in and now it still slips.

I think the trans started to hurt itself from no tq management and the power I was putting down.

I did notice this morning that when the car is still warming up and I drive it slow, the 2-3 shift is fine, but as soon as the temps get up and I get moving for a minute or so, it starts to happen.
Old 02-12-2008, 09:21 PM
  #7  
LS1Tech Sponsor
iTrader: (25)
 
performabuilt's Avatar
 
Join Date: Aug 2006
Location: BLOOMSBURG PA
Posts: 10,858
Received 78 Likes on 56 Posts

Default

Actually no the damage can take a while. Improper line control depending on how bad it is can kill the trans quickly or over a period of time, There is actually a GM TSB about the MAF and how it can damage the trans when out or calibration. The TSB has to do with contaminated MAFfrom over oiling filter. However engine mods not properly calibrated for can cause similar issues. The PO101 is likley what killed your trans you have now and could conceivably damage the new one if not addressed. I would get that corrected.
__________________
Built..PerformaBuilt..Tough

Call 888-744-6542


Old 02-12-2008, 09:31 PM
  #8  
TECH Enthusiast
Thread Starter
iTrader: (20)
 
dubrado's Avatar
 
Join Date: Apr 2003
Location: texas
Posts: 658
Likes: 0
Received 0 Likes on 0 Posts

Default

Originally Posted by performabuilt
Actually no the damage can take a while. Improper line control depending on how bad it is can kill the trans quickly or over a period of time, There is actually a GM TSB about the MAF and how it can damage the trans when out or calibration. The TSB has to do with contaminated MAFfrom over oiling filter. However engine mods not properly calibrated for can cause similar issues. The PO101 is likley what killed your trans you have now and could conceivably damage the new one if not addressed. I would get that corrected.
cool, thanks for the help
Old 02-12-2008, 10:00 PM
  #9  
LS1Tech Sponsor
iTrader: (25)
 
performabuilt's Avatar
 
Join Date: Aug 2006
Location: BLOOMSBURG PA
Posts: 10,858
Received 78 Likes on 56 Posts

Default

You are allways welcome
__________________
Built..PerformaBuilt..Tough

Call 888-744-6542


Old 02-16-2008, 08:46 PM
  #10  
FormerVendor
 
Gilbert@Ace Racing's Avatar
 
Join Date: Oct 2006
Location: D-F/W
Posts: 3,123
Likes: 0
Received 2 Likes on 2 Posts
Default

Just as an FYI for anyone who followed this thread and is interested to know the outcome.

The OP borught us the car, we removed and dissasembled the unit. What we found was the 3/4 clutches burnt, with more than a 1/4" of clearance in the stack when we got to it.

The accumulator pistons were plastic, one of them had broken. Basically the center of it, that rides on the pin, had been broken out and several small pieces of it were found throughout the tranmsission. Including one piece that was found in the 3rd gear feed hole of the valve body plate. In addition the accumulator spring was broken into pieces.

This unit had a shift kit installed previously, it is an example of why shift kits should be installed by professionals who understand what they are looking at. Not just professionals mind you... but pros who understand these units.

g

I will save these parts for getting pics up soon... I'm in computer hell right now or I'd do it tonight.

Last edited by Gilbert@Ace Racing; 02-16-2008 at 08:53 PM.




All times are GMT -5. The time now is 12:48 AM.