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.

? on dropping T-Case

Discussion in '1969-1972 K5 Blazer | Truck | Suburban' started by NuBombs72K5, May 12, 2001.

  1. NuBombs72K5

    NuBombs72K5 1/2 ton status

    Joined:
    Jan 21, 2001
    Posts:
    145
    Likes Received:
    0
    Location:
    Georgia
    I have a leak that must be coming from the rear transmission seal on my TH350. Once I drop the transfer case, what things should I look for. I would like to stop all the leaks before I put it back. I haven't worked on a 4x4 before so some guidance would be great. Thanks in advance.

    72 CST 350/350 NP205
     
  2. Steve_Chin

    Steve_Chin 1/2 ton status

    Joined:
    Mar 6, 2001
    Posts:
    1,126
    Likes Received:
    0
    Location:
    Foster City, CA, USA
    I don't have an automatic (and really haven't messed with one), but dropping the transfer case is simple. Drop the skid plate and its crossmember (if so eqipped). Drain it and strap it to a transmission jack. Remove the speedometer cable. Unbolt the driveshafts (the front driveshaft needs to be gotten at from on top) and remove. Remove the transfer case shift stick. Unbolt the transfer case from its mount. Unbolt the transfer case from the transmission tailstock. Slide it back out of the transmission and let it down.

    I *think* that the automatic and manual seal in the same fashion. If that is true, there is a seal inside of the transmission tailstock that seals against the drive coupler.

    When you reinstall, some of the bolts break through the transfer case housing, so they need sealant. Clean the threads of the bolts and in the transfer case housing well so that you don't get new leaks. Seal the transfer case to the adapter with a *light* bead of silicone.
     
  3. JST12

    JST12 1/2 ton status

    Joined:
    Aug 29, 2000
    Posts:
    192
    Likes Received:
    0
    Location:
    Garland, TX
    NuBomb, Steve,
    I just got finished rebuilding my TH350 and mounting to xfer case so I have a little info which may be helpful. It does not appear that there is any seal within the tailshaft section of the tranny. There is a bushing which is supplied by trans fluid. The fluid is free to leak into the tailshaft "chamber" between trans and xfer case which can help lube the governor gear. There is a drain hole in this section which goes into the pan. The only seal is a ~5 inch rubber oring between the xfer case and tranny. I'm thinking for simplicity, the xfer case can be pulled rearward about a 1/2 inch and rtv silicon gasket maker can be applied without the need for a new oring. This seal is non-pressurized and there isn't too much fluid flow behind it. Also, with the NP205, the bolts go through the TH350 tail flange and through the NP205 extension flange and don't need to be sealed. Hope this helps a little. JT
     

Share This Page