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  • AntMan
    AntMan - 1999 GMC Sierra 1500 - Transmissions & Drivetrains - 10/25/2014
    Why does the rear end of my truck shudder while I'm driving, even at slower speeds.
    As I was driving approx. 50kmh, my truck (2WD) suddenly started shuddering, like the back end was almost bouncing. I pulled over and checked under the truck, but it was at night, and I couldn't see much. I managed to get it home, but the noise continued the entire time.
     
    0 answer
  • AntMan
    AntMan - 1999 GMC Sierra 1500 - Transmissions & Drivetrains - 10/25/2014
    Why does the rear end of my truck shudder while I'm driving, even at slower speeds.
    As I was driving approx. 50kmh, my truck (2WD) suddenly started shuddering, like the back end was almost bouncing. I pulled over and checked under the truck, but it was at night, and I couldn't see much. I managed to get it home, but the noise continued the entire time.
     
    0 answer
  • AutoMD Member
    AutoMD Member - 2000 GMC Sierra 1500 - Transmissions & Drivetrains - 10/15/2014
    Hard to shift 5spd 4x4 v6.
    I just bought a GMC truck and it's hard to shift and if I don't press the clutch all the way down it slowly starts to move forward... It's just like the clutch is not being fully released... I took it to my mechanic and he told me since it's a hydraulic clutch it ...
     
    • alex
      10/15/2014 alex
      i would start with the slave and then the master i doubt you need a clutch unless you lost the throw out bearing.
  • Vincent
    Vincent - 2003 GMC Sierra 1500 - Transmissions & Drivetrains - 10/15/2014
    Replaced transmission now truck will not start
    I replaced my transmission with a used one out of a 2004 with a 6.0L now engine cranks but will not start. I called before it was done and local dealer told me the only difference was the MLP sensor is a 2 plugg connector vers a one. I switched them out before the ...
     
    • alex
      10/15/2014 alex
      i would start with checking fuzes and look for pinched wires. also check for extra wires down by the started. will it turn over and just not start or nothing?
      alex
      10/16/2014 Vincent
      Will crank fast but no fire.
      Checked and double checked and then rechecked the wires.
      And then plugged the old trany back in to the truck. Still no fire. Replaced the MLP with a new one still no fire.
      Getting a code no connection to tcm??
  • crazymomma
    crazymomma - 1995 GMC K1500 - Transmissions & Drivetrains - 9/20/2014
    1995 slave and master cylinder issues
    Just replaced clutch 9000 miles ago, slave and master cylinder last month but still no clutch! Pedal goes to floor unless pumped 3-4 times and this is only temporary. Mechanic has bled lines repeatedly and still if set overnight nothing. Any suggestions would be ...
     
    0 answer
  • fuelorman
    fuelorman - 1998 GMC K1500 - Transmissions & Drivetrains - 9/17/2014
    Automatic Transmission shifting hard
    All the time
     
    • alex
      9/14/2014 alex
      did you buy it this way or did it start one day. also first thing when you first put it in gear or all of the time. does it seem to shift when it should or at a higher than normal rpm?
      alex
      9/15/2014 fuelorman
      have had the truck since it was new has 186000 miles had maintenance religiously
      Started doing last year ,happens all the time shifts when it should just hard.
      Thank Alex
    • alex
      9/17/2014 alex
      i would look at the accumulator on the side of the transmission if that is full of stuff or if the spring broke inside of it it will not move to cushion the pressure of shifting gears. the shift kits that is supposed to make them shift harder put a stiffer spring in there. should just be a snap ring then the cover will come out with a spring and little piston, sorry it took so long to get back to you.
      alex
      9/18/2014 fuelorman
      Thanks Alex I will give it A look.
      Keith
  • GMC Vandura
    GMC Vandura - 1985 GMC K2500 - Transmissions & Drivetrains - 9/9/2014
    Transmission has blown gear I think
    My diesel pick up has had a blown transmission since it was givin to me five years ago (only used around yard) now I want to drive it as first truck until I can afford a nicer one. The transmission drives but only in Reverse, One and two. Drive does not work because ...
     
    0 answer
  • paulswitzer64
    paulswitzer64 - 1998 GMC Sonoma - Transmissions & Drivetrains - 9/7/2014
    Will a 2004 chevy 4x4 blazer transmission work
    trying to upgrade
     
    0 answer
  • paulswitzer64
    paulswitzer64 - 1998 GMC Sonoma - Transmissions & Drivetrains - 9/7/2014
    Will a 2004 chevy 4x4 blazer transmission work
    trying to put newer transmission in
     
    0 answer
  • tegan
    tegan - 2007 GMC Sierra 1500 - Transmissions & Drivetrains - 8/28/2014
    I got a tick when i give my truck throttle coming fom the rear end
    drive train or differential or wheel
     
    0 answer
  • AutoMD Member
    AutoMD Member - 1999 GMC Jimmy - Transmissions & Drivetrains - 7/20/2014
    Question about my 99 Jimmy
    Got a question about a 1999 Gmc Jimmy 4x4 4.3 with a 4l60E I bought about 6 months ago. got it for $600 here in ky from a lot. it was a trade in and the dealership just wanted it off their lot cause it has a salvage title. While I was checking it out I noticed it ...
     
    • Jimm
      7/20/2014 Jimm
      Need more information - is there any question with regard to these details or the vehicle?
  • AutoMD Member
    AutoMD Member - 1999 GMC Jimmy - Transmissions & Drivetrains - 7/20/2014
    Torque converter, p1870, bad tccm?
    After getting the motor in good shape, the rpm jump is still there. sluggish take off, 1st and 2nd hit hard and 4th seems not to exist. reverse lags. so, checked tranny fluid, kinda darkish red but at level. dropped the tranny pan and it was good. nothing on the ...
     
    • Jimm
      7/20/2014 Jimm
      P1870 Chevrolet / GM - Transmission Component Slipping

      Possible causes:
      - Trailer towing may set code
      - Check transmission fluid level
      - Internal transmission fault

      Possible causes / What does this mean?

      - Engine Light ON (or Service Engine Soon Warning Light)

      P1870 Chevrolet / GM Description

      Transmission is in 4th gear with Torque Converter Clutch (TCC) engaged and the Engine Control Module (ECM) has detected excessive slippage when comparing the input shaft speed to the output shaft speed

      The P1870 ( Transmission Component Slipping) code your car is displaying is usually due to the converter clutch shuttle/signal valve sticking in the valve body. The valve wears the bore in the casting and gets prone to stick when the transmission warms up. Most of the time this starts to happen in the 60-70,000 mile range, sometimes sooner depending on driving conditions. If driving condition are where the converter clutch is locking and unlocking frequently (areas with a lot of hills) the code might popup sooner.

      The valve sticking is only one of many possible causes for a P1870 code to set.
      The valve in yours could be the possible cause. There is a way to fix the valve problem WITHOUT replacing the valve body assembly. but...usually waiting too long after the symptoms show up, the torque converter will need to be replaced too, and you've already said it's been doing it for some time.

      When the code sets the PCM increases line pressure to "protect" the transmission and one of the side effects is rough shifts. It does this on each ignition cycle, so it might not do it when you first start driving some distance, but starts before you get to where your headed.
      Jimm
      7/20/2014 AutoMD Member
      hey thanks for responding back so quick. you pretty muched answered all my questions. got a few more. since the trans acts and shifts fine with a tad bit lag without the tccm, you think i could just get by with just replacing the valve with the teckpak valve or using the transgo kit. links are below. and of course the torque converter. im going to be probing all the electrical connections throughtout the jimmy to be sure everything is getting correct power along with checking the solonoids.
      Jimm
      7/20/2014 AutoMD Member
      and possibly replacing the tccm. 26 bucks at -u pull place.

      http://www.transgo.com/products.php


      http://www.teckpak-fitzall.com/spgm.cfm
  • AutoMD Member
    AutoMD Member - 1999 GMC Jimmy - Transmissions & Drivetrains - 7/19/2014
    Question about my 99 Jimmy
    Got a question about a 1999 Gmc Jimmy 4x4 4.3 with a 4l60E I bought about 6 months ago. got it for $600 here in ky from a lot. it was a trade in and the dealership just wanted it off their lot cause it has a salvage title. While I was checking it out I noticed it ...
     
    0 answer
  • MonsterMama64
    MonsterMama64 - 1997 GMC K1500 Suburban - Transmissions & Drivetrains - 7/17/2014
    While driving it felt like there was a very slight slip in the rear end, kinda like hitting a small patch of ice.
    Three weeks later felt the same thing again and recently, which would make it four months later, felt it while backing up.
     
    0 answer
  • AutoMD Member
    AutoMD Member - 2002 GMC Envoy - Transmissions & Drivetrains - 6/8/2014
    Replaced transmission now truck doesnt do anything
    I just changed transmission in my envoy. After completed started truck on blocks got it to 60km and everything died. Would i need to get a computer rest done on truck to reboot since transmission was taken out??
     
    • Chevy doctor
      6/8/2014 Chevy doctor
      Usually it is ideal to reset shift adapts with the scan tool when a transmission is replaced.hopefully you torqued flywheel/torque converter bolts. Make sure fluid level is good.
      Chevy doctor
      6/8/2014 Chevy doctor
      The pcm controls transmission shift points. Resetting adapts the pcm relearns new shift points.