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  • 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.
  • rudy
    rudy - 2000 GMC Sierra 1500 - Transmissions & Drivetrains - 6/4/2014
    My tow haul won't activate
    the light does not come or activate when pressed
     
    • Chevy doctor
      6/4/2014 Chevy doctor
      Replace shifter assembly. Replace all the time at the dealership.
  • rhondavas77
    rhondavas77 - 1998 GMC Jimmy - Transmissions & Drivetrains - 6/3/2014
    Can it be ANYTHING else besides needing the whole transmission rebuilt like maybe a shift cable or sensor of some sort?
    I started noticing that my Jimmy wasn't shifting properly about a year ago. It seemed that when I would come to a complete stop that when I would push the gas pedal to accelerate the truck that it felt as it would hesitate and then kinda jump in to gear but once it ...
     
    • rick
      12/27/2012 rick
      I'm not the best tranny dude but from what you told it's not sounding real good . In most cases 1st and reverse are the last to quit . But as you said it's been acting up for a long time . Hate to say but they don't get better with time . The good news is a used tranny for your blazer is not a lot of $ . Check some junk yards and the want adds . Should be able to get one for less than $500 . And it can be changed in about 3 - 4 hours as a shade tree mec .
    • Jimm
      12/27/2012 Jimm
      Need more information - how many miles on the transmission? How many miles since the previous fluid and filter change? It would seem, without inspection - that the transmission is in need of service - maybe the clutch and band replacement.
    • Boe
      6/3/2014 Boe
      im going to say it straight you need to have it rebuilt I had the same problem and ignored it till one day it just destroyed its self if you have any questions feel free to contact me james.boden.1@us.af.mil ok
  • lisa.r.watson
    lisa.r.watson - 2000 GMC Jimmy - Transmissions & Drivetrains - 6/3/2014
    My check 4 wheel drive light JUST came on. The truck is stuttering and dragging. Has started to stall as well. PLS HELP!
    I am a single Mom who NEEDS my baby!!! If ANYONE can offer me any CHEAP guidance I wld SOOOOOOO appreciate it!!!!
     
    • Boe
      6/3/2014 Boe
      go under the truck on the passenger side of the front differential their should be a solenoid sticking out of it disconnect the wire going to it and drive it around if this doesn't fix it you may have a vacuum leak if you have any questions feel free to contact me james.boden.1@us.af.mil ok
  • AutoMD Member
    AutoMD Member - 2003 GMC Sierra 2500 HD - Transmissions & Drivetrains - 5/29/2014
    Why wont my transmisssion engage?
    My transmission went out in my 2003 GMC Sierra 2500HD so I replaced it with a 1999 GMC Suburban 4L80E transmission but it will not engage. Could you help me?
     
    0 answer