How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Marc Your Own Question
Marc
Marc, Technician
Category: Car
Satisfied Customers: 1888
Experience:  33 years exp. automotive repair NYS emisisions repair cert.
44459
Type Your Car Question Here...
Marc is online now
A new question is answered every 9 seconds

1997 GMC Suburban: wheel drive..warning..reverse..transmission shifts

Customer Question

I have a 1997 GMC SuburbanXXXXX1500 SLT. With no warning, I have no reverse and the transmission shifts late, but forward gears are strong. Never had any problems with the transmission before. All maintenance records complete. Tell me what you think.
Submitted: 11 years ago.
Category: Car
Expert:  Marc replied 11 years ago.

  The only thing the two problems would have in common would be the main control seperator plate (could be worn or damaged Unless it is two seperate problems .


 Did you check the fluid level that will usualy effect reverse first.


 If it is seperate problems the reverse clutch could be burnt damaged or worn out.


 Or the direct reverse servo o ring could be cut or broken.


  Going with the two seperate problems the main control solenoid stuck, damaged, or solenoid circuit could be the problem. For late shifting.


  Late shifting could also be a powertrain control moduel(blown fuse) or circuit problem.


  A weak pump will cause both problems also. You could have low aplication pressures to the bands and or clutches.( you have to run line pressure tests)

       

Customer: replied 11 years ago.
Reply to enginboy's Post: After having no problems with this transmission whatsoever and always running strong, one morning I went out and it wouldn't go in reverse. It did go into all forward drive gears, so I went ahead and drove it to see if it was OK to go to the repair shop. It did shift, but shifted late and at that point I went around the block and came home and parked it. Please keep in mind that it has to be the same problem. It all happened at once. I only drive this about 300 miles a year and I've never had inXXXXXand drive like a Grandma. Transmission fluid looks good. The maintenance is impecable and that's why this seems so strange.
Expert:  Marc replied 11 years ago.

 If this thing sits for long periods you might try warming it up and flushing the trans (profesionaly) and see if that loosens up whatever is hanging (sticky check balls).


  One other thing could be pluged filter or damaged some how.


The main seperator plate Pcm  and pump pressures are what have to be investigated first then.


  The easiest thing to check is the PCM fuse.

Customer: replied 11 years ago.
Reply to enginboy's Post: Thanks for the info. If this helps me, I will be contacting you. Thank you.
Expert:  Marc replied 11 years ago.
 

You ask me what I thought thats all I could think of without seeing it first hand good luck  post back if you have anymore questions.
Customer: replied 11 years ago.
Reply to enginboy's Post: Would the ODS throw up trouble codes for transmission problems?
Expert:  Marc replied 11 years ago.
 

whats ODS?
Customer: replied 11 years ago.
Reply to enginboy's Post: Onboard Diagnostics System
Expert:  Marc replied 11 years ago.
 

Yes OBD II could set codes for certain failures If the fuse is good and the failures are monitored by sensors.

JustAnswer in the News:

 
 
 
Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.
 
 
 

What Customers are Saying:

 
 
 
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
< Previous | Next >
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
  • used your service this weekend with "Trecers" help. thank you ,thank you, thank you. replaced an A/C fan motor. Local Auto Zone had part. $15.00 "tracer" fee and $40.00 for parts, I saved several hundreds of dollers at a shop. i will recommend you and use you in the future. David L. Richmond, TX
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil Marysville, CA
  • Lurch. Thank you very much. I had real doubts about this website but your promptness of response, quick followup and to the point answer with picture was incredible. Charles Walnut Creek, CA
  • As a single woman, I really appreciate an excellent and affordable opinion.
    Thank you Geordie, I will not hesitate to contact justanswer in the future!
    Sue Charleston, WV
  • Another great insight to what may be the problem. I will have my mechanic take a look at it tomorrow. Thanks again, Frank...you do indeed know your stuff. Jim Castleberry, FL
  • Excellent reply, and also very quick. Really sounds like the Expert knows what he is talking about. I will be back to use your service when I need more help with my RV. Dutch USA
 
 
 

Meet The Experts:

 
 
 
  • Chris (aka-Moose)

    Chris (aka-Moose)

    Technician

    Satisfied Customers:

    1006
    16 years of experience
< Last | Next >
  • http://ww2.justanswer.com/uploads/MU/muddyford/2012-6-13_1204_1.64x64.png Chris (aka-Moose)'s Avatar

    Chris (aka-Moose)

    Technician

    Satisfied Customers:

    1006
    16 years of experience
  • http://ww2.justanswer.com/uploads/TE/TedG/2012-6-15_14759_avaLarge.64x64.jpg Ted G.'s Avatar

    Ted G.

    ASE Certified Technician

    Satisfied Customers:

    1694
    20 years auto repair experience, ASE Master Tech, Mechanical Failure consultant, Expert Witness
  • http://ww2.justanswer.com/uploads/joecamel90/2008-11-13_03615_head_shot.jpg George H.'s Avatar

    George H.

    ASE Certified Technician

    Satisfied Customers:

    1447
    ASE Master Tech 15+ yrs, AAS Automotive Technology, Factory trained Asian specialist
  • http://ww2.justanswer.com/uploads/BL/Bluegorilla/2012-6-21_16298_cam.64x64.JPG GM Tech (Cam)'s Avatar

    GM Tech (Cam)

    Auto Service Tech

    Satisfied Customers:

    669
    GM Grand Master Technician 2007. 14 years experience.
  • http://ww2.justanswer.com/uploads/AM/amedee/2013-10-24_23656_Amedee1.64x64.jpg Amedee's Avatar

    Amedee

    Former ASE Master Tech

    Satisfied Customers:

    2406
    ASE certified tech advanced level specialist. Wisconsin certified emissions state inspector
  • http://ww2.justanswer.com/uploads/SU/supermechanic/2013-8-23_03546_500.64x64.jpg Jerry's Avatar

    Jerry

    Master Mechanic

    Satisfied Customers:

    2123
    ASE master, 30+ years. All makes and models. Trouble shooter, shop forman, service manager
  • http://ww2.justanswer.com/uploads/CR/crzydrvr00/2013-11-3_12123_246347.64x64.jpg Richard's Avatar

    Richard

    ASE Certified Technician

    Satisfied Customers:

    992
    12 years Ford Lincoln/Mercury Jaguar dealership as a technician and shop foreman reparing all makes