check your owner's manual. The early AWD systems ('01, '02,...) were non-Haldex and supposedly susceptible to differences in tread depth and wear. This could put extra strain on the AWD system and possibly do damage. This was well-noted in my 02 V70XC owner's manual.
Whether in the real world differences in tire sizes, tread depth or wear actually impact AWD function I can't say; I've never tried it. Your MY04 may have Haldex so maybe it won't be an issue in your case but you should see some warning in your manual if it is!
2007 XC70, 206,000 miles
2002 V70XC, 130,000 miles, parts car
Bookmarks