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  • 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
  • AutoMD Member
    AutoMD Member - 2007 GMC Yukon - Transmissions & Drivetrains - 5/6/2014
    My Yukon Denali wont move when I put it into drive. Could it possibly be the transmission control box or the torque conv
    My Yukon Denali wont move when I put it into drive. Could it possibly be the transmission control box or the torque converter or is it definitely the transmission? Also, how do we get up to date with all the technical service bulletins? Are those free if we take it ...
     
    • GT500Knights
      5/6/2014 GT500Knights
      Check transmission fluid level. The owners manual usually states how to check the fluid level--it is usually a complex set of instruction. For example, to check the fluid level on my car, 15 minutes of highway driving must be done. Then find a place to park, and shift the shifter through all of the notches, leaving it in each gear for a few seconds. Then return shift lever to park, let sit for three minutes, and then check fluid level. The procedure may be a little different for your car. But since your car won't move definitely check out the fluid level. Eve without the proper checking procedure there should still be some fluid showing up on the dipstick. Faulty torque converter can also be an issue. If the converter has too large a clearance between the turbine and impeller, nothing will move. Another important component to check out is the differential. I've seen the internal gears completely worn inside the differential. This specific situation involved a completely deteriorated ring gear and pinion gear. The worn pinion gear would spin, but since the teeth were all worn away, there was nothing for anything to grab. This will usually be caused by improperly maintained gear oil inside the differential.
  • AutoMD Member
    AutoMD Member - 2007 GMC Yukon - Transmissions & Drivetrains - 5/6/2014
    My Yukon Denali wont move when I put it into drive. Could it be the transmission control box or the torque converter...
    My Yukon Denali wont move when I put it into drive. Could it possibly be the transmission control box or the torque converter or is it definitely the transmission? Also, how do we get up to date with all the technical service bulletins? Are those free if we take ...
     
    0 answer
  • AutoMD Member
    AutoMD Member - 2007 GMC Yukon - Transmissions & Drivetrains - 5/6/2014
    My Yukon Denali wont move when I put it into drive. Could it be the transmission control box or the torque converter...
    My Yukon Denali wont move when I put it into drive. Could it possibly be the transmission control box or the torque converter or is it definitely the transmission? Also, how do we get up to date with all the technical service bulletins? Are those free if we take ...
     
    0 answer
  • AutoMD Member
    AutoMD Member - 2007 GMC Sierra 1500 - Transmissions & Drivetrains - 4/30/2014
    When I come to a stop in my truck, I will be stopped for a second or two and my whole truck drops down. Runs fine. Why
    I pull a trailer. My transmission shifts fine. It's just weird when I come to a stop and it feels like it's almost shifting down. But I have no issues when driving
     
    0 answer
  • AutoMD Member
    AutoMD Member - 2002 GMC Envoy - Transmissions & Drivetrains - 4/27/2014
    Transmission won't engage.
    I replaced motor with one that was 4wd had my trans checked over and switched shift silonoids 170000 miles. No warning lights. It will not engage at all, will only go into park and will start in nutruel. Is there something he might have forgot to hook up inside the ...
     
    • HouseCallAuto
      4/27/2014 HouseCallAuto
      You have left out some details that I do not want to have to assume. Please explain how all this happened? Are you saying that the transmission was fine until the engine went bad and you replaced the engine? What computer are you referring to that came with the motor? Tell the full story from the beginning when everything was OK. Go
  • AutoMD Member
    AutoMD Member - 1997 GMC Jimmy - Transmissions & Drivetrains - 4/13/2014
    Removing rear axle on a 97 hmm jimmy
    I'm trying to replace rear axle bearing and seal.I have pulled the pin and c clip.the right side slid right out.but the other won't.it spins but won't pull out.what can it be.and how do I get it out
     
    • bear.1216
      4/13/2014 bear.1216
      There is a C-clip on the end of each axle shaft that holds it inside the differential. Did you pull both clips. Once the clips are pulled the axle shafts usually slide right out easily. Sometimes they get hung up near the bearing or on the gear teeth. You can either attach a slide hammer to the wheel studs or run a long pipe thru the other side and punch it out. It it rare for them to stick unless the wheel bearings are bad. If that is the case you will need to use a puller. If it is stuck it will not push in either. You have to push the axlshafts in to remove the retaining C-clips. Are you sure you removed both clips.
 
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