Newbie with Funny Tranny

[Stevels]

Hi All, First, let me say I really have been looking for posts for what I am sure is a very well documented problem, but I can not seem to get the info I need, and I am posting a thread that I hope will not annoy the senior members. Please excuse my ignorance, as I am new to all of this stuff - but I mean well. With that said:

I have a recently aquired 1991 350SDL with 205K miles in what seems to be amazing overall condition. I have just converted it to run on Veg oil, and it all is working great so far.

Just the other day, I noticed that the trnasmission is shifting hard. It seems to happen in all gears, especially first to second, but they all seem pretty hard. I checked the trannsmission fluid and it seems fine.

The wierd thing is that the problem, while always worse when the car is cold, is nontheless seemingly intermittent. Sometimes it seems to ride just fine, and then in an hour or two, it starts shifting hard again.

I fear am facing either catstrophic and expensive transmission failure (isn't 205K miles a lot for a transmission?) or some simple vacuum issue that I do not really understand.

I am not a complete mechanical moron, but I am near that side of the fence. Still, I did the conversion myslef and I have access to a lift and nice tools. Can anyone point me to a thread where I can troubleshoot some basic transmission hard shift diagnosis?

Also, is there anything I can premptively do to avoid bending a rod, blowing a timing chain and other stuff that I hear I should be suspect of in the 350 SDL? Having invested a great deal of time and money into my veggie conversion, I really want to maintain this great car as best as I can.

Thanks for all your consideration.

BTW, here are some pics of the WVO installation

http://www.steveadler.com/wvo.htm