While I don't think anyone can say for sure if one specific thing like this could result in lower ranking, IMHO a truncated title is not generally going to be the culprit of rankings drop. However, I do think a truncated title can significantly lower click-thru rate on your organic listings, which could be a factor in rankings (i.e. higher click-thru rate could equal higher rankings).

I always encourage the sites that I SEO to adhere to Google's character limitations and make the most out of the organic real estate Google gives you. It's your chance to get someone to come to your site. If the title/and or description is truncated, it has less chance of being compelling, or containing the information that makes someone want to click through and visit your pages.

Hope that's helpful!

Dana