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D3B transmission question

BushMike · 2026-09-23 19:22

I pulled the engine for a rebuild and pulled the 3F/3R tranny as well. Nearly a 10,000hr machine. It barely moved itself in 3rd, Was weak in 2nd and would not spin the tracks in 1st against a stump. Today I pulled the transmission down and was pretty shocked to see what literally look like brand new discs and plates. All (5) clutch stack-ups spec in the middle of the NEW tolerance per the CAT powertrain SPECIFICATIONS manual. The teflon piston rings on (4) of the pistons are actually loose in the bores. NO Resistance whatsoever placing the pistons in the bores. If this were the issue and clutches slipping, wouldn't the plates be all burnt to hell? Is my slippage issue possibly the torque converter? Is the TQ in a D3B a weak link? Any advice appreciated.

Replies7
  1. #1BushMike2026-09-23 19:25

    Pics attached

  2. #2pittsburgh cat man2026-09-23 20:01

    first look at the orifice it is plastic on bottom of the pressure control valve (the top section of the valves) they can break and plug the orifice that will take the transmission to primary pressure it will make transmission pretty gutless

  3. #3BushMike2026-09-23 20:09

    PCM…is this orifice inside the valve body on the inside/top of the transmission

  4. #4BushMike2026-09-23 20:17

    item 12 or 34?

  5. #5pittsburgh cat man2026-09-23 20:33

    12 and 19 orifice and seal

  6. #6BushMike2026-09-23 20:47

    Thank you! I will check them tomorrow. Are they under the cover with all the bolts?

  7. #7pittsburgh cat man2026-09-23 21:01

    have to take all the 5/16 bolts out remove top plate then flip next section it is on side facing clutch packs They habit of the plastic top of orifice coming lose they used to be pretty cheap