Hi,
It's not a great name, as you may already know. Yes, the .com appears to be fully developed, and appeals to an American audience, and this is usually a good sign. Unfortunately, however, "auto lenders" is an awkward term... even for our dear friends in the States.
And, with the .co.uk suffix, which one assumes will cater solely to a UK audience, this "awkwardness" becomes even more acute.
The only real acid test 'though is to check the Google keyword results for "auto lenders", under the UK settings...
Good luck,