Jump to content

4L60E 3-2 downshift issue

Genuinefine409

Recommended Posts

Genuinefine409 Enthusiast

Genuinefine409

Posted
Posted

I rebuilt my 4L60E in my 1995 K1500; everything went very well, except one thing. When downshifting from 3rd to 2nd I get a slip/bump/slide. I can go up through all the gears, it spins the tires hitting second, very firm going into 3rd and 4th. But if I am cruising in 3rd or 4th and it kicks down to 2nd, it will slip for a split second and then grab, almost like it flares before it grabs. Going from 2nd to 1st it is ok, just 3rd to 2nd. If I am off the throttle and downshift it manually, it pulls instantly into 2nd. If I am at part throttle and pull it manually into 2nd, it slips just as if it kicks down on its own.

 

http://www.sonnax.com/parts/2432

 

I installed this, has anyone had any issues with this? Could this be causing my issues? The trans was fine before, this was the only "add-on" I did. I did a shift kit and other upgrades, but nothing I did could cause this issue i would think. The truck never did this before the rebuild, and i rebuilt it due to rear planetary failure. All the clutches and everything were still good at time of rebuild.

 

If anyone has any experience and can offer some feedback, it would be greatly appreciated.

 

 

Thanks,

 

Barry

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Latest Articles

  • Posts

    • CaptPat51
      6.2L V8 with Supercharger

      By CaptPat51 · Posted

      i guess that's.... no??:)
    • CaptPat51
      Is 2027 GMC Yukon Getting a 682-HP Supercharged V8?

      By CaptPat51 · Posted

      Would you supercharge the 6.2L on a 2021 GMC Yukon Denali XL with ProCharger?.... 605HP is the stated number without going crazy - it's not the LT4 682HP package, but I'm tempted to install it... This vehicle was ... not... recalled on the engine swap - but I don't really know if that means ...don't do it... or do it;)    Maybe i should start a prediction market pool on it in case it blows up;)   Any thoughts appreciated - I already OWN the supercharger - stopped the installation when the recall was announced and now it's taking up space in storage until I can solve an electrical issue with the vehicle...  4th GMC suburban-equivalent truck - I like them a lot - when they don't a) discharge their batteries randomly, or b) throw a rod at highway speeds;)
    • CaptPat51
      2021 Yukon Electrical Issues

      By CaptPat51 · Posted

      We tested the sleep mode with an ammeter in series with the negative battery terminal - 30amp fused - so we do know the actual shutdown and non-shutdown current draws and timing of the shutdown sequence.  We just have no protocol information to determine what module is issuing the network keep alive.  
    • Vu1can
      Brake Pad Warning Message

      By Vu1can · Posted

      TrueBlue...Even if you don't have that info stuff displayed, If Mr. Computer thinks there's something you should know about, it will pop up a warning message no matter what else is being displayed. I keep the speedometer displayed all the time, yet the brake pad message pops up anyway.
    • CaptPat51
      2021 Yukon Electrical Issues

      By CaptPat51 · Posted

      BTW, the 11.5amp draw is all the usual systems active - it's not a single draw - that's the "we're all awake" state of the vehicle - forinstance if the power steps are actuated, the draw will spike to 22amps for that operation.  when the battery is disconnected and then reconnected, the vehicle shuts down that one time only - and we see a 10-15minute progression down 11.5  10.5  9. 8 6. 5. 1.6... 500ma... and then off to sleep at 40 milliamp... as expected.  So we know it's a module that is simply refusing to allow the SDGM to proceed to the sleep state.  We do NOT think it is the telematics VIM module - since we already duplicated the problem with the "VIM bypass" solution installed (we reverted that since it also disables the gmc app - but it does not appear that the telematics system is the culprit).  We've replaced the rear heater control module, tested without the wireless charger, and the other modules on CAN Bus 5 - but still something is keeping us awake and removing X2 from SDGM allows sleep to proceed.  We cannot diagnose from OBD since OBD drops off at about the 9volt level in sleep mode and we can't communicate with the vehicle - also we can't trace the SDGM internal packets from the OBD side - we have Autel Ultra.   Any ideas on why disconnecting X2 would allow sleep to proceed appreciated.  This is no longer a repair situation - this vehicie is simply unusable in this condition and NOBODY at GMC Dealer can even understand what it is doing.  This is crazy.  We made these systems too complex and now we're paying the price.

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...