The drive started out just fine. Had the top down and was heading up north on the freeway at around 70. I got off the freeway and started going down some backroads that required me to do more than just leave the car in 5th gear. The drive was probably a total of around 2 hours, and as it progressed I noticed it become harder and harder to shift, to the point where about an an hour and a half into the drive I was stuck at stop signs trying to shove the shifter into first gear while waving people through.
Since my clutch was replaced about a month ago, I've had to put the shifter into 4th before I get it into 1st (I was under the impression that the clutch pedal wasn't disengaging all of the way because of some extra padding I have under it). Other than that, it was fine. This was much worse, however. Even after tightening the clutch cable just a little bit I had gear grinding while shifting up and shifting down from and into 2nd, 3rd, and 4th. Additionally, and this is what really throws me off, if I took my foot off of the brake the car would sometimes travel forward slowly while on level ground even with the clutch pedal depressed all of the way (like I was driving an automatic).
This and the shifting problems lead me to believe that my clutch isn't disengaging all of the way. I checked to see if the hole in my firewall had re-opened, but it hasn't. On the other hand, all of this springs up just after I replace the transmission oil. I jacked up the front of the car today and made sure that I had it filled all of the way. Sure enough, when I removed that plug oil started to spill out.
This is the correct fill plug, right?
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Lastly, I let the car sit for a while (about 5 hours) after that long drive, and then took it home for a short one that night. Aside from a little bit of grinding getting in and out of 3rd and 4th, it was fine. No shoving it into first or second. Could the heat of the oil have something to do with what's going on?
I've been following some threads dealing with transmission oil and transmission problems, and I've been thinking of trying the Valvoline VR1 SAE 50 that Alvon has talked about putting in his his transmission after having bad luck with the GL-1, but I have a feeling that it would be wishful thinking to say that the new GL-1 is causing all of these problems.