Question about coolant leaks and the clutch release bearing

[arcano]

For well over a year my '98 SE has been making a howling noise when I press the clutch pedal, especially when cold. I was sure it was the release bearing, so I was planning to redo the whole clutch while I was in there. I had already bought the parts (dealer had a sale on parts for older models, and I got a complete kit for about $300). The dealer also quoted me $400 for the labor, which I think is reasonable considering the amount of work involved. I am also way overdue on changing the transmission and transfer case oil, and I want to switch to synthetic. So, I bought 8 quarts of Redline MT-90, but I have been waiting to redo the clutch before I put it in (this stuff is expensive).

 

On what I thought was a completely unrelated issue, for a very long time the truck had a small coolant leak I could not find. It was small enough that I could just check my coolant level every couple of weeks and top it off as necessary. About a month ago I finally found the leak: it was one of the heater hoses that goes into the cabin. The hose had a small crack, and coolant would spray onto the firewall and drip down on to the top of the transmission, around it, and pool on the skid plate, where it would dry before it had a chance to drip to the floor. A couple of plugs and a "U" shaped hose and the leak was fixed, bypassing the whole heater thing (no need for it in Panama).

 

Now here is the strange part: A few weeks after fixing the coolant leak the clutch howling started going away, and now it is completely gone! The only thing I can think of is that the coolant leak was somehow related to the howling, and now that the leak is fixed the problem has gone away. Maybe some coolant was somehow getting to the clutch release bearing, but I don’t know if it’s possible.

 

So, here are some questions for the experts: Can these two problems really be related? Can coolant make the clutch release bearing howl, and can it fix itself after fixing the leak? Is the lack of howling a good sign, or should I still be worried about an imminent clutch failure? Also, if I go ahead and change the transmission and transfer case oil to synthetic, will I have to drain the oil if I still need to redo the clutch in the near future?