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 Gary Your Own Question
Gary, GMC Technician
Category: GM
Satisfied Customers: 16646
Experience:  15 years gm master tech/15 years ASE master tech
Type Your GM Question Here...
Gary is online now
A new question is answered every 9 seconds

GMC: ton..automatic transmission..4th gear or down shifts..slipping

This answer was rated:

Hello, I have a 98 3/4 ton GMC with the 4L60-E automatic transmission. Sometimes (half the time) it shifts hard into 4th gear or down shifts hard into 3rd. It sort of feels like it is slipping when it does happen. If I am accelerating hard it doesn't happen at all. It only happens when I am accelerating normally up to highway speed. I've had the tranny fluid flushed and replaced and have added a tranny suplement to no avail. Any suggestions? Could it be a shift solenoid? Is it severe?
more than likley when you accelerate hard there is enough fluid preasure to over come a ripped ,torn seal,and possibly the 3-4 clutches are worn out..i would highly recomend that it be removed and gone is more than fixable right now..the more you drive it the more damage can be done
Gary and other GM Specialists are ready to help you
Customer: replied 7 years ago.

This would not be due to the shift solenoids then? I do have 157,000 miles on the truck. What sort of work does it require to go throught the 3-4 clutch? I'm in Alaska and people REALLY like to charge big money for any transmission work. Just looking for a little more clarity on the whole idea of the transmission.




if it was a shift solnoid it would affect more than one gear..for any 3-4 clutch work the trans needs to be removed and dissasembled