Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Mystery: How can this happen?

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by Blue85, Feb 28, 2004.

  1. Blue85

    Blue85 Troll Premium Member

    Joined:
    Jul 26, 2000
    Posts:
    9,090
    Likes Received:
    489
    Location:
    Grand Rapids area
    I am not sure what happened yesterday. In my normal state of wheeling /forums/images/graemlins/k5.gif, I came to a stop light (sense sarcasm?). When the light turned green, the truck was clearly in neutral. I tried shifting through all the gears (700R4), got out to make sure the rear driveshaft was still there and locked the hubs. I was very unpopular. Still nothing in 4HI. Did I blow the tranny, lose all the fluid or blow the T-case? /forums/images/graemlins/confused.gif Shifting to park caused a ratcheting noise which I knew was the parking pawl. The problem was the transfer case. I thought about rebuilding it with a Dodge fixed yoke (NP 208) /forums/images/graemlins/grin.gif. Then I shifted to 4LO and could feel the truck drop into gear. So the NEXT green light, I drove it into the corner gas station in 4LO, expecting to hear parts grinding and scattering. But it was fine. I shifted back to 4HI and 2HI and both worked. /forums/images/graemlins/confused.gif I drove home and floored it after a couple more lights and everything worked perfectly. I tried moving the T-case shifter all around and brake torqueing and could not duplicate the condition.

    What could have caused this? If the shift linkage goes further forward than the 2HI position, can it disengage the drive path through the 'case? Is this a sign of worn shift forks or something? I've never had any problems with this transfer case before.
     
  2. BurbinOR

    BurbinOR 3/4 ton status

    Joined:
    Feb 17, 2000
    Posts:
    5,829
    Likes Received:
    0
    Location:
    Oregon
    Sounds like your transfer case came out of gear. /forums/images/graemlins/waytogo.gif
     
  3. tRustyK5

    tRustyK5 Big meanie Staff Member Super Moderator GMOTM Winner Author

    Joined:
    Jul 23, 2000
    Posts:
    36,184
    Likes Received:
    1,392
    Location:
    E-town baby!
    Sounds like the T-case found 'N' all by itself. Could be worn shifter parts, or even the plastic tabs on the range fork. Could also be a weak detent ball spring on the T-case side of the shifter assembly.

    Rene
     
  4. TruckNutzDude

    TruckNutzDude 1/2 ton status

    Joined:
    Mar 31, 2003
    Posts:
    3,532
    Likes Received:
    0
    Location:
    Agawam, MA
    your shifter might be out of adjustment or maybe you have worn engine/tranny mounts and that caused it to pop out of gear. /forums/images/graemlins/dunno.gif
     
  5. fortcollinsram

    fortcollinsram 1/2 ton status

    Joined:
    Nov 8, 2001
    Posts:
    2,261
    Likes Received:
    0
    Location:
    Fort Collins, CO
    my truck did the EXACT same thing when i had the 700/208 combo in it...When I swapped the 465/205 in I pulled the 208 apart and one of the forks (the mode fork I think) had been grinding against the planetary gear and was FUBAR'd and it would slip into neutral...Oh yeah, those little nylon pads were in about a million pieces in the botton of the case...



    Chris
     
  6. Blue85

    Blue85 Troll Premium Member

    Joined:
    Jul 26, 2000
    Posts:
    9,090
    Likes Received:
    489
    Location:
    Grand Rapids area
    Thanks, that's good info.

    As an update, it did it to me again, this time after a hard stop. Thinking back, the first time may have been a hard stop, too. I will adjust the linkage a bit to see if it helps, but I am starting plans for a 208 rebuild.
     
  7. 84_Chevy_K10

    84_Chevy_K10 Banned

    Joined:
    May 30, 2001
    Posts:
    17,669
    Likes Received:
    0
    Location:
    IL, USA
    I have a known good 208 with adapter if you need it, PM me if interested.
     
  8. offroad87

    offroad87 Registered Member

    Joined:
    Feb 2, 2004
    Posts:
    57
    Likes Received:
    0
    Location:
    Atoka, TN
    last night when was leaving a stop light I gagged the throttle, i broke the slip yoke,(anybody have a good one they want to get rid of?) brand new Ujoint, and cracked my 208 all the way around. i already found another 208 though. how difficult are they to rebuild?
     
  9. ford_assassin

    ford_assassin 1/2 ton status

    Joined:
    Nov 8, 2003
    Posts:
    101
    Likes Received:
    0
    Location:
    Bakersfield, Ca.
  10. Blue85

    Blue85 Troll Premium Member

    Joined:
    Jul 26, 2000
    Posts:
    9,090
    Likes Received:
    489
    Location:
    Grand Rapids area
    Mystery solved. [​IMG]
    The destroyed range fork was allowing the planetary gearset to go into neutral without the shifter actually moving. While the total shift pattern is 2H, 4H, N, 4LO, that actually comes from two places. The mode fork selects 2WD/4WD by engaging the drive sprocket for the chain. The range fork changes the configuration of the planetary gearset to select HI, N, LO. I was skipping from 2HI to N because the mode fork was fine, but the deceleration force from braking hard was pulling the planetaries forward enough to disengage them.

    I modified the fork on the left (Ford style) to take Chevy style fork pads, used serious glue on the pads and problem solved!

    I believe the original problem was misadjusted shift linkage, probably from lowering the T-case without readjusting the linkage. Just because I still had all 4 modes didn't mean everything was running right, I guess.

    I did a slip yoke elimination on the 208 at the same time.
     

Share This Page