Jump to content

Help, 4x4 not engaging

thefox1

Recommended Posts

thefox1 Enthusiast

thefox1

Posted
Posted

I have a 99 GMC Yukon 5.3l with an automatic transfer case. A couple of weeks ago I had the seals on the front wheels that go into the diff. changed, and since then the 4x4 no longer engages. Could the replacement of theses leaking seals cause my problem?

Ape0r Enthusiast

Ape0r

Posted
Posted
I have a 99 GMC Yukon 5.3l with an automatic transfer case. A couple of weeks ago I had the seals on the front wheels that go into the diff. changed, and since then the 4x4 no longer engages. Could the replacement of theses leaking seals cause my problem?

 

 

 

 

Did the mechanic remember to plug back in all the connectors he took out? =). Do the LED indicators on your switch do anything funny? These switches are known for failure, could be coincidence.

crazymjb Enthusiast

crazymjb

Posted
Posted

The only thing I could think of is that it has to be locked in 4WD during the procedure(or the diff falls apart and you gotta open it up), so maybe they screwed it up then.

 

I don't mean to hijack the thread... But I heard with pushbuttons systems from 4HI to 4LOW, and VV, the truck has to be in Neutral. Can anyone confirm this? Also, will it allow you to change between the two when in drive, or does it have a neutral safety switch(if that is the case)?

 

Thanks,

 

Mike

thefox1 Enthusiast

thefox1

Posted
  • Author
Posted
The only thing I could think of is that it has to be locked in 4WD during the procedure(or the diff falls apart and you gotta open it up), so maybe they screwed it up then.

 

I don't mean to hijack the thread... But I heard with pushbuttons systems from 4HI to 4LOW, and VV, the truck has to be in Neutral. Can anyone confirm this? Also, will it allow you to change between the two when in drive, or does it have a neutral safety switch(if that is the case)?

 

Thanks,

 

Mike

 

 

 

 

 

Yes, to go from 4Hi (or 2Hi) to 4Lo, you have to be in neutral.

Ape0r Enthusiast

Ape0r

Posted
Posted
The only thing I could think of is that it has to be locked in 4WD during the procedure(or the diff falls apart and you gotta open it up), so maybe they screwed it up then.

 

I don't mean to hijack the thread... But I heard with pushbuttons systems from 4HI to 4LOW, and VV, the truck has to be in Neutral. Can anyone confirm this? Also, will it allow you to change between the two when in drive, or does it have a neutral safety switch(if that is the case)?

 

Thanks,

 

Mike

 

 

 

 

This is correct. The truck must be in neutral to shift into 4-LO. I worked at chevy dealer last summer.. had a guy bring in a gorgeous 2500HD D/A because he couldn't be bothered to read his manual when it wouldn't shift into 4-LO. Oh well, didn't mind cruising around in it for a few minutes!

crazymjb Enthusiast

crazymjb

Posted
Posted

Does it require you to be in nuetral before it will even function(planetary gearset, correct?), or can I mechanically desacrate the system by hitting the button(in which case I will put a new set of buttons in with shields)? Also, how much reduction is offered in 4LO?

 

Mike

Ape0r Enthusiast

Ape0r

Posted
Posted
Does it require you to be in nuetral before it will even function(planetary gearset, correct?), or can I mechanically desacrate the system by hitting the button(in which case I will put a new set of buttons in with shields)? Also, how much reduction is offered in 4LO?

 

Mike

 

 

 

 

If you try to shift into 4-LO without the trans in neutral the lights will just blink at you and be like :cheers:.

 

4-LO gives a 2.72:1 reduction.

 

4-Lo + First gear + 3.73 rear = 2.72*3.06*3.73 = 31.05:1 overall reduction :P.

 

Just imagine what that does at the wheels when the engine is cranking out its peak torque at the flywheel! If you want to find out stick it in 4-lo and floor that sucker!.. but be sure your head is against the headrest first..

crazymjb Enthusiast

crazymjb

Posted
Posted

And I got the 350 In there(In 2Hi can one spin the tires with an empty bed?) :cheers:

 

I am hesitant to screw around with the engine because its got 80K on it and is working flawlessly.

 

BTW, I should have it registered and in my driveway by friday, I am so excited :P

 

Thanks,

 

Mike

thefox1 Enthusiast

thefox1

Posted
  • Author
Posted
And I got the 350 In there(In 2Hi can one spin the tires with an empty bed?) :cheers:

 

I am hesitant to screw around with the engine because its got 80K on it and is working flawlessly.

 

BTW, I should have it registered and in my driveway by friday, I am so excited :P

 

Thanks,

 

Mike

 

 

 

 

 

As long as you don't do what my buddy did. He put the pedal to the floor in snow with the steering completly turned to the right, then shifted it in reverse at 2500rpm. Bye bye tranny!!

  • 8 months later...
Zeppelin264 Enthusiast

Zeppelin264

Posted
Posted

Hi, i know this post is old but did you ever deicde what the deal was with the seals and the 4x4 not engaging?

 

i recently did this and have the same problem and im wondering if you have to be locked in to make sure the diff dosent fall apart.

 

Thanks

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.

  • Forum Statistics

    250.6k
    Total Topics
    2.7m
    Total Posts

  • Member Statistics

    343,007
    Total Members
    8,960
    Most Online
    Brendan C
    Newest Member
    Brendan C
    Joined

  • Who's Online   2 Members, 0 Anonymous, 1,201 Guests (See full list)

  • Latest Articles

  • Posts

    • Grumpy Bear
      The Peckish Synapse

      By Grumpy Bear · Posted

      You can always count on greed to prey on ignorance and stupidity.    Friend bought a 2019 Ford Flex and asked me about using Valvoline R&P 5W30 in it. Told him give the miles on it and the fact it wasn't yet using oil that it was a good plan. He uses a Valvoline quick change shop for his oil service.   First they tell him that isn't the oil the OEM recommends. He told them he didn't care what the OEM thought. Then they floated the, "But it will void your warranty"    His reply was it's a 2019, there is no warranty and informed them their knowledge of the law was lacking.    Then they tell him 'But it will ruin your motor"!.    Mine to ruin he says. Finally they give in and charge him 150% the semi-syn price    Point it the brainwash is so embedded that even the service industry is drunk on their swill. The public is right behind them. Echoing the same lies on every forum and media platform. If the end goal is indeed EV then I'd say that ship is about built. 
    • CamGTP
      Gas Prices

      By CamGTP · Posted

      Diesel hit $6.00 here today at the truck stop.   Payed $2.79 for E85 today too.
    • richard wysong
      Electrical Problem - solved

      By richard wysong · Posted

      Thanks for posting, I'm sure it will help someone
    • Brendan C
      2026 6.6 L5P oil cooler leaking oil at 4,000 miles

      By Brendan C · Posted

      New to diesel trucks. I happened to find my oil cooler leaking oil externally with only 4,000 miles on the truck. I didn’t realize this was an issue until I started researching it. Dealer is going to replace it under warranty but I’m wondering if there’s anything GM is working on to fix this issue. I’ve heard the oil filter used is the same as they use on their V6 motors and that’s what is causing the problems. Should I switch to a bigger filter or keep using the OEM recommended? 
    • Vu1can
      Seems to be Missing a lot of Updates

      By Vu1can · Posted

      So, GMCustomerService:  Judging by the Update History pictured above, is this truck missing any updates that it actually needs. If it's just for the infotainment system, the radio is working fine and no trouble with SeriusXM. and Android Auto is working fine wirelessly with my phone. Some months ago, an update notice was sent to my truck. I approved the update and it finished saying that the update was successful, but it seems that whatever that update was, it didn't actually get installed - at least not if I'm to go by the Update History shown above.   So, again, are there any updates that this truck really should have? I've checked with my dealer but they're reluctant or commit to anything and if I want them to check, they require a $200.00 fee just to check it out and then I'd have to pay for the actual update(s).    Ignorance is bliss, and if none of the updates goes to fixing any mechanical discrepancies, I'll just leave things as is.  

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...