Clutch issues, need help!

[BKs50trimGST]

this has happened numerous times in the past two months. Scenario: I'll be driving on the highway for about 20min. at a constant 55-75mph, then when i wanna downshift or put it into a different gear it won't let me do anything unless i pump the clutch, the clutch itself feels really loose/soft like there is no pressure, when i swapped my 7bolt for the 6bolt i have now i also replaced the clutch master cylinder, so i have a brand new one in there, could it be faulty install? tranny maybe going? please help me, i need to fix this problem. it's been getting alot worse lately to.

[blageo23]

Have you adjusted the clutch pedal? http://www.roadraceengineering.com/clutchandflywheeltech.htm
About 3/4 way down there is how you do it if you dont know. I also had this problem with mine when i put the 6bolt in(with an ACT flywheel and 2600). I also had a new clutch master and slave cylenders. I adjusted and it helped for awhile but then it went back to the way it was. Then I adjusted again and it was fine for awhile again. Another thing that helped was when you put my tranny back in another time we put grease on the TOB and the Falcrum and the slace where it hits the fork. that helped out the most.
Mike

[scheides]

might consider swapping out the slave cylinder as well...

[tim]

Was it properly bled? Air in the system would definitely give it a loose, sloppy feeling.

EDIT: When you pump the pedal does it feel like it gets more stiff and less sloppy?

[BKs50trimGST]

yeah, when u pump it i can put it into gear, but the wierd thing is this only happens when i drive in it for awile on the highway.