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d 8n transmission hot

burns ยท 2018-01-02 04:08

i have a d8n that transmission temp light is coming on. ive changed oil and filter and checked screen flushed radiator. my belt pulleys were worn so I changed them, im getting good cooling threw the radiator and threw the transmission cooler, ive put a temp gun on the transmission and it was getting hot. I put the transmission into neutral and rev the engine and it will not cool, what throws me is that when I stick it into gear the temp will go down. ive checked pump pressure and its in spec, my next step will beto do a stall test on the t/c has anyone had a similar issue?

Replies2
  1. #1Mark2502018-01-05 23:50

    hi, there are too many versions of the D8N transmission to help without serial number Mark

  2. #2ATCme2018-01-08 15:55

    Funny my Komatsu D65 does the exact same thing. Only stays cool when it's under load at high rpm. Running in neutral does nothing to cool it. I suspect either my t\c regulator valve or my relief valve is sticking or broken. I've eliminated everything else beside a t/c rebuild at this point.